Hyperledger Iroha documentation

_images/iroha_logo.png

Warning

For secure deployment on platforms other than new Linux versions, please read this note first before deploying Iroha in production.

Welcome! Hyperledger Iroha is a simple blockchain platform you can use to make trusted, secure, and fast applications by bringing the power of permission-based blockchain with Crash fault-tolerant consensus. It’s free, open-source, and works on Linux and Mac OS, with a variety of mobile and desktop libraries.

You can download the source code of Hyperledger Iroha and latest releases from GitHub page.

This documentation will guide you through the installation, deployment, and launch of Iroha network, and explain to you how to write an application for it. We will also see which use case scenarios are feasible now, and are going to be implemented in the future.

As Hyperledger Iroha is an open-source project, we will also cover contribution part and explain you a working process.

Overview of Iroha

What are the key features of Iroha?

  • Simple deployment and maintenance
  • Variety of libraries for developers
  • Role-based access control
  • Modular design, driven by command–query separation principle
  • Assets and identity management

In our quality model, we focus on and continuously improve:

  • Reliability (fault tolerance, recoverability)
  • Performance Efficiency (in particular time-behavior and resource utilization)
  • Usability (learnability, user error protection, appropriateness recognisability)

Where can Iroha be used?

Hyperledger Iroha is a general purpose permissioned blockchain system that can be used to manage digital assets, identity, and serialized data. This can be useful for applications such as interbank settlement, central bank digital currencies, payment systems, national IDs, and logistics, among others.

For a detailed description please check our Use Case Scenarios section.

How is it different from Bitcoin or Ethereum?

Bitcoin and Ethereum are designed to be permissionless ledgers where anyone can join and access all the data. They also have native cryptocurrencies that are required to interact with the systems.

In Iroha, there is no native cryptocurrency. Instead, to meet the needs of enterprises, system interaction is permissioned, meaning that only people with requisite access can interact with the system. Additionally, queries are also permissioned, such that access to all the data can be controlled.

One major difference from Ethereum, in particular, is that Hyperledger Iroha allows users to perform common functions, such as creating and transferring digital assets, by using prebuilt commands that are in the system. This negates the need to write cumbersome and hard to test smart contracts, enabling developers to complete simple tasks faster and with less risk.

How is it different from the rest of Hyperledger frameworks or other permissioned blockchains?

Iroha has a novel, Crash fault tolerant consensus algorithm (called YAC [1]) that is high-performance and allows for finality of transactions with low latency.

Also, Iroha’s built-in commands are a major benefit compared to other platforms, since it is very simple to do common tasks such as create digital assets, register accounts, and transfer assets between accounts. Moreover, it narrows the attack vector, improving overall security of the system, as there are less things to fail.

Finally, Iroha is the only ledger that has a robust permission system, allowing permissions to be set for all commands, queries, and joining of the network.

[1]Yet Another Consensus

How to create applications around Iroha?

In order to bring the power of blockchain into your application, you should think first of how it is going to interface with Iroha peers. A good start is to check Concepts and Architecture section, explaining what exactly is a transaction and query, and how users of your application are supposed to interact with it.

We also have several client libraries which provide tools for developers to form building blocks, such as signatures, commands, send messages to Iroha peers and check the status.

Concepts and Architecture

Iroha is a system that can work with different concepts, and for your convenience we would like you to look through them so you could familiarise yourself with what you will be dealing with. That can be done in “Core concepts section”.

To learn, what Iroha is made of, please check out “What’s inside Iroha?”

Core concepts

Why Iroha runs in a network? How to understand the objects inside and outside the system? How peers in the network collaborate and decide which data to put into the blockchain? We will look through the basics of Iroha in this section.

Account

An Iroha entity that is able to perform specified set of actions. Each account belongs to one of existing domains.

An account has some number of roles (can be null) — which is a collection of permissions. Only grantable permissions are assigned to an account directly.

Asset

Any countable commodity or value. Each asset is related to one of existing domains. For example, an asset can represent any kind of such units - currency unit, a bar of gold, real estate unit, etc.

Block

Transaction data is permanently recorded in files called blocks. Blocks are organized into a linear sequence over time (also known as the block chain) [1].

Blocks are signed with the cryptographic signatures of Iroha peers, voting for this block during consensus. Signable content is called payload, so the structure of a block looks like this:

Iroha Block Structure

Outside payload

  • signatures — signatures of peers, which voted for the block during consensus round

Inside payload

  • height — a number of blocks in the chain up to the block
  • timestamp — Unix time (in milliseconds) of block forming by a peer
  • array of transactions, which successfully passed validation and consensus step
  • hash of a previous block in the chain
  • rejected transactions hashes — array of transaction hashes, which did not pass stateful validation step; this field is optional

Client

Any application that uses Iroha is treated as a client.

A distinctive feature of Iroha is that all clients are using simple client-server abstractions when they interact with a peer network: they don’t use any abstractions which are specific for blockchain-related systems. For example, in Bitcoin clients have to validate blocks, or in HL Fabric they need to poll several peers to make sure that a transaction was written in a block, whereas in HL Iroha a client interacts with any peer similarly to a single server.

Command

A command is an intention to change the state of the network. For example, in order to create a new role in Iroha you have to issue Create role command.

Consensus

A consensus algorithm is a process in computer science used to achieve agreement on a single data value among distributed processes or systems. Consensus algorithms are designed to achieve reliability in a network involving multiple unreliable nodes. Solving that issue – known as the consensus problem – is important in distributed computing and multi-agent systems.

Consensus, as an algorithm

An algorithm to achieve agreement on a block among peers in the network. By having it in the system, reliability is increased.

For consensus as Iroha’s component, please check this link.

Domain

A named abstraction for grouping accounts and assets. For example, it can represent an organisation in the group of organisations working with Iroha.

Peer

A node that is a part of Iroha network. It participates in consensus process.

Permission

A named rule that gives the privilege to perform a command. Permission cannot be granted to an account directly, instead, account has roles, which are collections of permissions. Although, there is an exception, see Grantable Permission.

List of Iroha permissions.

Grantable Permission

Only grantable permission is given to an account directly. An account that holds grantable permission is allowed to perform some particular action on behalf of another account. For example, if account a@domain1 gives the account b@domain2 a permission that it can transfer assets — then b@domain2 can transfer assets of a@domain1 to anyone.

Proposal

A set of transactions that have passed only stateless validation.

Verified Proposal

A set of transactions that have passed both stateless and stateful validation, but were not committed yet.

Query

A request to Iroha that does not change the state of the network. By performing a query, a client can request data from the state, for example a balance of his account, a history of transactions, etc.

Quorum

In the context of transactions signing, quorum number is a minimum amount of signatures required to consider a transaction signed. The default value is 1. For MST transactions you will need to increase that number.

Each account can link additional public keys and increase own quorum number.

Role

A named abstraction that holds a set of permissions.

Signatory

Represents an entity that can confirm multisignature transactions for an account. It can be attached to account via AddSignatory and detached via RemoveSignatory.

Transaction

An ordered set of commands, which is applied to the ledger atomically. Any non-valid command within a transaction leads to rejection of the whole transaction during the validation process.

Transaction Structure

Payload stores all transaction fields, except signatures:

  • Time of creation (unix time, in milliseconds)
  • Account ID of transaction creator (username@domain)
  • Quorum field (indicates required number of signatures)
  • Repeated commands which are described in details in commands section
  • Batch meta information (optional part). See Batch of Transactions for details

Signatures contain one or many signatures (ed25519 public key + signature)

Reduced Transaction Hash

Reduced hash is calculated over transaction payload excluding batch meta information. Used in Batch of Transactions.

Transaction Statuses

Hyperledger Iroha supports both push and pull interaction mode with a client. A client that uses pull mode requests status updates about transactions from Iroha peer by sending transaction hashes and awaiting a response. On the contrary, push interaction is performed by listening of an event stream for each transaction. In any of these modes, the set of transaction statuses is the same:

_images/tx_status.png

Note

We’ve written a great Medium article about Status streaming feature in Iroha. Check it out and let us know what you think in the comments!

Transaction Status Set
  • NOT_RECEIVED: requested peer does not have this transaction.
  • ENOUGH_SIGNATURES_COLLECTED: this is a multisignature transaction which has enough signatures and is going to be validated by the peer.
  • MST_PENDING: this transaction is a multisignature transaction which has to be signed by more keys (as requested in quorum field).
  • MST_EXPIRED: this transaction is a multisignature transaction which is no longer valid and is going to be deleted by this peer.
  • STATELESS_VALIDATION_FAILED: the transaction was formed with some fields, not meeting stateless validation constraints. This status is returned to a client, who formed transaction, right after the transaction was sent. It would also return the reason — what rule was violated.
  • STATELESS_VALIDATION_SUCCESS: the transaction has successfully passed stateless validation. This status is returned to a client, who formed transaction, right after the transaction was sent.
  • STATEFUL_VALIDATION_FAILED: the transaction has commands, which violate validation rules, checking state of the chain (e.g. asset balance, account permissions, etc.). It would also return the reason — what rule was violated.
  • STATEFUL_VALIDATION_SUCCESS: the transaction has successfully passed stateful validation.
  • COMMITTED: the transaction is the part of a block, which gained enough votes and is in the block store at the moment.
  • REJECTED: this exact transaction was rejected by the peer during stateful validation step in previous consensus rounds. Rejected transactions’ hashes are stored in block store. This is required in order to prevent replay attacks.
Pending Transactions

Any transaction that has lesser signatures at the moment than quorum of transaction creator account is considered as pending. Pending transaction will be submitted for stateful validation as soon as multisignature mechanism will collect required amount of signatures for quorum.

Transaction that already has quorum of signatures can also be considered as pending in cases when the transaction is a part of batch of transactions and there is a not fully signed transaction.

Batch of Transactions

Transactions batch is a feature that allows sending several transactions to Iroha at once preserving their order.

Each transaction within a batch includes batch meta information. Batch meta contains batch type identifier (atomic or ordered) and a list of reduced hashes of all transactions within a batch. The order of hashes defines transactions sequence.

Batch can contain transactions created by different accounts. Any transaction within a batch can require single or multiple signatures (depends on quorum set for an account of transaction creator). At least one transaction inside a batch should have at least one signature to let the batch pass stateless validation.

You can read an article about batches on our Contributors’ Page on Medium.

Atomic Batch

All the transactions within an atomic batch should pass stateful validation for the batch to be applied to a ledger.

Ordered Batch

Ordered batch preserves only the sequence of transactions applying to a ledger. All the transactions that able to pass stateful validation within a batch will be applied to a ledger. Validation failure of one transaction would NOT directly imply the failure of the whole batch.

Multisignature Transactions

A transaction which has the quorum greater than one is considered as multisignature (also called mst). To achieve stateful validity the confirmation is required by the signatories of the creator account. These participants need to send the same transaction with their signature.

Validation

There are two kinds of validation - stateless and stateful.

Stateless Validation

Performed in Torii. Checks if an object is well-formed, including the signatures.

Stateful Validation

Performed in Verified Proposal Creator. Validates against World State View.

[1]https://en.bitcoin.it/wiki/Block

Entity-relationship model

Each Hyperledger Iroha peer has a state, called “World State View”, which is represented by a set of entities and relations among them. To explain which entities exist in the system and what are the relations, this sections includes ER diagram and an explanation of its components.

ER diagram
_images/er-model.png
Peer
  • address — network address and internal port, is used for synchronization, consensus, and communication with the ordering service
  • public_key — key, which will be used for signing blocks during consensus process
Asset
  • asset_id — identifier of asset, formatted as asset_name#domain_id
  • domain_id — identifier of domain, where the asset was created, references existing domain
  • precision — size of fractional part
Signatory
  • public_key — a public key
Domain
  • domain_id — identifier of a domain
  • default_role — a default role per user created in the domain, references existing role
Role
  • role_id — identifier of role
RoleHasPermissions
  • role_id — identifier of role, references existing role
  • permission_id — identifier of permission
Account
  • account_id — identifier of account, formatted as account_name@domain_id
  • domain_id — identifier of domain where the account was created, references existing domain
  • quorum — number of signatories required for creation of valid transaction from this account
  • transaction_count – counter of transactions created by this account
  • data — key-value storage for any information, related to the account. Size is limited to 268435455 bytes (0x0FFFFFFF) (PostgreSQL JSONB field).
AccountHasSignatory
  • account_id — identifier of account, references existing account
  • public_key — a public key (which is also called signatory), references existing signatory
AccountHasAsset
  • account_id — identifier of account, references existing account
  • asset_id — identifier of asset, references existing asset
  • amount — an amount of the asset, belonging to the account
AccountHasRoles
  • account_id — identifier of account, references existing account
  • role_id — identifier of role, references existing role
AccountHasGrantablePermissions
  • account_id — identifier of account, references existing account. This account gives grantable permission to perform operation over itself to permittee.
  • permittee_account_id — identifier of account, references existing account. This account is given permission to perform operation over account_id.
  • permission_id — identifier of grantable_permission

What’s inside Iroha?

HL Iroha network consists of several essential components that provide the communication between the nodes. You can learn about them below.

Iroha Architecture Diagram

Torii

Entry point for clients. Uses gRPC as a transport. In order to interact with Iroha anyone can use gRPC endpoints, described in Commands and Queries sections, or use client libraries.

MST Processor

Multisignature Transactions Processor

It is an internal gRPC service that sends and receives messages from other peers through Gossip protocol. Its mission is to send out multisignature transactions that have not received enough signatures to reach the quorum until it is reached.

Peer Communication Service

Internal component of Iroha - an intermediary that transmits transaction from Torii through MstProcessor to Ordering Gate. The main goal of PCS is to hide the complexity of interaction with consensus implementation.

Ordering Gate

It is an internal Iroha component (gRPC client) that relays transactions from Peer Communication Service to Ordering Service. Ordering Gate recieves proposals (potential blocks in the chain) from Ordering Service and sends them to Simulator for stateful validation. It also requests proposal from the Ordering Service based on the consensus round.

Ordering Service

Internal Iroha component (gRPC server) that receives messages from other peers and combines several transactions that have been passed stateless validation into a proposal. Each node has its own ordering service. Proposal creation could be triggered by one of the following events:

  1. Time limit dedicated to transactions collection has expired.
  2. Ordering service has received the maximum amount of transactions allowed for a single proposal.

Both parameters (timeout and maximum size of proposal) are configurable (check environment-specific parameters page).

A common precondition for both triggers is that at least one transaction should reach the ordering service. Otherwise, no proposal will be formed.

Ordering service also performs preliminary validation of the proposals (e.g. clearing out statelessly rejected transactions from the proposal).

Verified Proposal Creator

Internal Iroha component that performs stateful validation of transactions contained in received proposal from the Ordering Service. On the basis of transactions that have passed stateful validation verified proposal will be created and passed to Block Creator. All the transactions that have not passed stateful validation will be dropped and not included in a verified proposal.

Block Creator

System component that forms a block from a set of transactions that have passed stateless and stateful validation for further propagation to consensus.

Block creator, together with the Verified Proposal Creator form a component called Simulator.

Block Consensus (YAC)

Consensus, as a component

Consensus is the heart of the blockchain - it preserves a consistent state among the peers within a peer network. Iroha uses own consensus algorithm called Yet Another Consensus (aka YAC).

You can check out a video with a thorough explanation of the principles of consensus and YAC in particular here.

Distinctive features of YAC algorithm are its scalability, performance and Crash fault tolerance.

To ensure consistency in the network, if there are missing blocks, they will be downloaded from another peer via Synchronizer. Committed blocks are stored in Ametsuchi block storage.

For general definition of the consensus, please check this link.

Synchronizer

Is a part of consensus. Adds missing blocks to peers’ chains (downloads them from other peers to preserve consistency).

Ametsuchi Blockstore

Iroha storage component, which stores blocks and a state generated from blocks, called World State View. There is no way for the client to directly interact with Ametsuchi.

World State View

WSV reflects the current state of the system, can be considered as a snapshot. For example, WSV holds information about an amount of assets that an account has at the moment but does not contain any info history of transaction flow.

Quick Start Guide

In this guide, we will create a very basic Iroha network, launch it, create a couple of transactions, and check the data written in the ledger. To keep things simple, we will use Docker.

Note

Ledger is the synonym for a blockchain, and Hyperledger Iroha is known also as Distributed Ledger Technology framework — which in essence is the same as “blockchain framework”. You can check the rest of terminology used in the Core concepts section.

Prerequisites

For this guide, you need a machine with Docker installed. You can read how to install it on a Docker’s website.

Note

Of course you can build Iroha from scratch, modify its code and launch a customized node! If you are curious how to do that — you can check Building Iroha section. In this guide we will use a standard distribution of Iroha available as a docker image.

Starting Iroha Node

Creating a Docker Network

To operate, Iroha requires a PostgreSQL database or RocksDB. If you prefer PostgreSQL, you will need a container running it alongside Iroha.

Let’s start with creating a Docker network, so containers for Postgres and Iroha can run on the same virtual network and successfully communicate. In this guide we will call it iroha-network, but you can use any name. In your terminal write following command:

docker network create iroha-network

Starting PostgreSQL Container

Note

You do not need to start this container if your plan is to use Iroha with RocksDB and not PostgreSQL. Just skip to the next step.

Now we need to run PostgreSQL in a container, attach it to the network you have created before, and expose ports for communication:

docker run --name some-postgres \
-e POSTGRES_USER=postgres \
-e POSTGRES_PASSWORD=mysecretpassword \
-p 5432:5432 \
--network=iroha-network \
-d postgres:9.5 \
-c 'max_prepared_transactions=100'

Note

If you already have Postgres running on a host system on default port (5432), then you should pick another free port that will be occupied. For example, 5433: -p 5433:5432

Creating Blockstore

Before we run Iroha container, we may create a persistent volume to store files, storing blocks for the chain. It is done via the following command:

docker volume create blockstore

Preparing the configuration files

Note

To keep things simple, in this guide we will create a network containing only a single node. To understand how to run several peers, follow Deploy

Now we need to configure our Iroha network. This includes creating a configuration file, generating keypairs for a users, writing a list of peers and creating a genesis block.

Don’t be scared away — we have prepared an example configuration for this guide, so you can start testing Iroha node now. In order to get those files, you need to clone the Iroha repository from Github or copy them manually (cloning is faster, though).

git clone -b main https://github.com/hyperledger/iroha --depth=1

Hint

--depth=1 option allows us to download only the latest commit and save some time and bandwidth. If you want to get a full commit history, you can omit this option.

There is a guide on how to set up the parameters and tune them with respect to your environment and load expectations: Configure. We don’t need to do this at the moment.

Starting Iroha Container

We are almost ready to launch our Iroha container. You just need to know the path to configuration files (from the step above).

Let’s start Iroha node in Docker container with the following command:

docker run --name iroha \
-d \
-p 50051:50051 \
-v $(pwd)/iroha/example:/opt/iroha_data \
-v blockstore:/tmp/block_store \
--network=iroha-network \
-e KEY='node0' \
hyperledger/iroha:latest

Note

If you are using Iroha with RocksDB, please add --entrypoint irohad to these parameters, to skip the PostgreSQL container check.

Note

To use metrics with Docker please also set up the port -p7001:7001 and edit the config.docker file with 0.0.0.0:7001.

If you started the node successfully you would see the container id in the same console where you started the container.

Let’s look in details what this command does:

  • docker run --name iroha \ creates a container iroha
  • -d \ runs container in the background
  • -p 50051:50051 \ exposes a port for communication with a client (we will use this later)
  • -v YOUR_PATH_TO_CONF_FILES:/opt/iroha_data \ is how we pass our configuration files to docker container. The example directory is indicated in the code block above.
  • -v blockstore:/tmp/block_store \ adds persistent block storage (Docker volume) to a container, so that the blocks aren’t lost after we stop the container
  • --network=iroha-network \ adds our container to previously created iroha-network for communication with PostgreSQL server
  • -e KEY='node0' \ - here please indicate a key name that will identify the node allowing it to confirm operations. The keys should be placed in the directory with configuration files mentioned above.
  • hyperledger/iroha:latest is a reference to the image pointing to the latest release

You can check the logs by running docker logs iroha.

You can try using one of sample guides in order to send some transactions to Iroha and query its state.

Integrated Projects

One of the ideas of the Hyperledger Consortium is to create solutions that could work together to provide the best blockchain experience possible. In Iroha we believe that integration of other awesome Hyperledger tools and solutions is a way to make Iroha better for your use-cases. That is why we have worked on integrations with several projects and would like to tell you more about what Iroha can work with.

Hyperledger Ursa

Hyperledger Ursa is a shared cryptographic library that would enable people (and projects) to avoid duplicating other cryptographic work and hopefully increase security in the process. The library would be an opt-in repository for projects (and, potentially others) to place and use crypto. Hyperledger Ursa consists of sub-projects, which are cohesive implementations of cryptographic code or interfaces to cryptographic code.

You can easily build Iroha with Ursa library by adding just one flag during the build. It will allow you to use crypto algorithms from Ursa library instead of standard Iroha cryptography. With the development of new libraries in Ursa more and more options will be available to you!

Note

Currently, we only get ed25519 SHA-2 algorithm from Ursa. If you like, you can contribute to the code to add more options.

To allow using the default ed25519/sha3 cryptography algorithm as well as the ones from Ursa, we use Multihash public key format for the latter. You can learn more about the keys.

Hyperledger Explorer

Hyperledger Explorer is a blockchain module and one of the Hyperledger projects hosted by The Linux Foundation. Designed to create a user-friendly Web application, Hyperledger Explorer can view, invoke, deploy or query blocks, transactions and associated data, network information (name, status, list of nodes), chain codes and transaction families, as well as any other relevant information stored in the ledger.

Here you can learn how you can use Explorer with Iroha.

Hyperledger Burrow

Hyperledger Burrow provides a modular blockchain client with a permissioned smart contract interpreter partially developed to the specification of the Ethereum Virtual Machine (EVM).

So, with HL Burrow you can use Solidity smart-contracts on Iroha. Click below to learn more.

HL Burrow Integration

As Iroha maintainers, we have received many questions and requests for custom smart-contracts support from our users. And to provide them more freedom in fulfilling their business needs, we integrated HL Burrow EVM – another great project of the Hyperledger greenhouse, into Iroha.

Note

In the context of Iroha, HL Burrow provides an Ethereum Virtual Machine that can run Solidity smart-contracts. We did our best to provide you with the best user experience possible – and to use it with Iroha, you only need to add a CMake flag during Iroha build and it will start working right away.

There are official docker images built with Hyperledger Burrow <https://hyperledger.github.io/burrow/#/> Integration. Please replace hyperledger/iroha:latest with hyperledger/iroha-burrow:latest to use them.

You can read about Solidity smart-contract language here, if you are new to this language.

How it works

For this integration, we have created a special Call Engine command in Iroha, as well as a special Engine Receipts query for retrieving the results of the command.

The command

In the command, you can:

Сreate a new contract account in EVM

If the callee in the CallEngine is not specified and the input parameter contains some bytecode, a new contract account is created.

Call a method of a previously deployed contract

If the callee is specified, then the input is treated as an ABI-encoded selector of a method of the callee contract followed by the arguments.

Hint

It is much like deploying a contract or calling a contract function in Ethereum depending on the contents of the data field of the eth_sendTransaction message call. See ABI-specification for details.

The query

To query the outcome of a CallEngine command one should use the Engine Receipts query. The output of any computations inside the EVM will not be available for the caller until it has been written to the ledger (that is, the block that has the respective Iroha transaction has been committed). Among the other data, the EngineReceipts query will return an array of log entries generated in the EVM during the CallEngine execution.

Hint

A common way for dApps developers to let interested parties see the outcome of a contract execution is to emit an event with some data before exiting a contract function so that this data is written to the Event Log. Ethereum Yellow Paper defines a log entry as a 3-tuple containing the emitter’s address, an array of 32-byte long topics and a byte array of some data.

Passing Ordering and arguments which are list of values is being done by sending JSON string with parameters. See examples for more examples.

Running Native Iroha Commands in EVM

With HL Burrow integration, you can also use native commands to change the state of Iroha.

The integration mechanism of Burrow EVM empowers Iroha application developers with a tool able to directly act on the Iroha state from smart contracts code thus providing foundation for programmable business logic extensions of the built-in Iroha commands system. Conditional asset transfers, transaction fees, non-fungible assets and so on are just a few examples of such extensions. The tricky part here is that the Iroha data model is quite different from that of Ethereum. For instance, in Ethereum there is only one kind of built-in asset (Eth) therefore getting an account balance in EVM context simply means returning the balance property of the account. In Iroha, on the other hand, an account can have multiple assets, or not have assets at all, so any function that returns an account balance must take at least one extra argument – the asset ID. Same logic applies to transferring/sending assets from account to account.

As a solution to this data model mismatch problem we introduce so-called Service Contracts in Burrow that are “aware” of the Iroha data model and expose an API to interact with Iroha state (query balances, transfer assets and so on).

Note

You can check out Burrow documentation for more information on Natives and external dispatchers.

Schematically the interaction between different parts of the system looks as follows:

_images/natives.svg

Attention

From the Burrow EVM perspective such Service Contract is hosted in a Native external VM and is callable via the same interfaces as if it was deployed at some special address in the EVM itself. These methods are used specifically for Iroha integration, so the address of the Service Contract can only be found while working with it via Iroha.

Current release of the Iroha EVM wrapper contains a single service contract deployed at the address A6ABC17819738299B3B2C1CE46D55C74F04E290C (the last 20 bytes of the keccak256 hash of the string ServiceContract) which exposes the following Iroha commands and queries:

Integrated Commands/Queries
S No. Signature of exposed API methods Arguments
1 addAssetQuantity(string,string) asset_id, amount
2 addPeer(string,string) address, peer_key
3 addSignatory(string,string) account_id, public_key
4 appendRole(string,string) account_id, role_name
5 createAccount(string,string,string) account_name, domain_id, public_key
6 createAsset(string,string,string) asset_name, domain_id, precision
7 createDomain(string,string) domain_id, default_role
8 detachRole(string,string) account_id, role_name
9 removePeer(string) public_key
10 removeSignatory(string,string) account_id, public_key
11 setAccountDetail(string,string,string) account_id, key, value
12 setAccountQuorum(string,string) account_id, quorum
13 subtractAssetQuantity(string,string) asset_id, amount
14 transferAsset(string,string,string,string,string) src_account_id, dest_account_id, asset_id, description, amount
15 getAccount(string) account_id
16 getBlock(string) height
17 getSignatories(string) account_id
18 getAssetBalance(string,string) account_id, asset_id
19 getAccountDetail()  
20 getAssetInfo(string) asset_id
21 getRoles()  
22 getRolePermissions(string) role_id
23 getPeers()  

Hint

From a developer’s perspective calling a function of a native contract is no different from calling a method of any other smart contract provided the address of the latter is known:

bytes memory payload = abi.encodeWithSignature(“getAssetBalance(string,string)”, “myacc@test”, “coin#test”);

(bool success, bytes memory ret) = address(0xA6ABC17819738299B3B2C1CE46D55C74F04E290C).delegatecall(payload);

Here a special kind of EVM message calls is used - the delegatecall, which allows a contract to dynamically load and run code from a different address at runtime in its own execution context.

See also

Now, let’s move to the usage examples

Examples of How to Use HL Burrow EVM

This section demonstrates a few examples of how one can deploy and run smart contracts in an EVM on top of Iroha blockchain.

To interact with Iroha, we will be using a Python Iroha client. Assuming Iroha node is listening on a local port 50051, the client code will look something like:

import os
from iroha import Iroha, IrohaCrypto, IrohaGrpc

iroha = Iroha('admin@test')
net = IrohaGrpc('127.0.0.1:50051')

admin_key = os.getenv(ADMIN_PRIVATE_KEY, IrohaCrypto.private_key())
# Code for preparing and sending transaction
Case 1. Running computations and storing data

As the first example we will take the Subcurrency smart contract from the Solidity documentation. The contract code is the following (the reader may refer to the original documentation to understand what each line of the contract code means, if necessary):

contract Coin {
    // The keyword "public" makes variables
    // accessible from other contracts
    address public minter;
    mapping (address => uint) public balances;

    // Events allow clients to react to specific
    // contract changes you declare
    event Sent(address from, address to, uint amount);

    // Constructor code is only run when the contract
    // is created
    constructor() public {
        minter = msg.sender;
    }

    // Sends an amount of newly created coins to an address
    // Can only be called by the contract creator
    function mint(address receiver, uint amount) public {
        require(msg.sender == minter);
        require(amount < 1e60);
        balances[receiver] += amount;
    }

    // Sends an amount of existing coins
    // from any caller to an address
    function send(address receiver, uint amount) public {
        require(amount <= balances[msg.sender], "Insufficient balance.");
        balances[msg.sender] -= amount;
        balances[receiver] += amount;
        emit Sent(msg.sender, receiver, amount);
    }
}

To start off, we need to compile the source code above to the bytecode. For that we can either use the full-fledged Solidity compiler or the Web-based Remix IDE .

Having got the bytecode, we can now send a transaction from the Python Iroha client which will deploy the contract to the EVM:

import os
from iroha import Iroha, IrohaCrypto, IrohaGrpc

iroha = Iroha('admin@test')
net = IrohaGrpc('127.0.0.1:50051')

admin_key = os.getenv(ADMIN_PRIVATE_KEY, IrohaCrypto.private_key())
bytecode = ("608060405234801561001057600080fd5b50336000806101000a81548173ffff”
            "ffffffffffffffffffffffffffffffffffff021916908373ffffffffffffffff"
            ...
            "030033")

tx = iroha.transaction([
    iroha.command('CallEngine', caller='admin@test', input=bytecode)
])
IrohaCrypto.sign_transaction(tx, admin_key)

net.send_tx(tx)
for status in net.tx_status_stream(tx):
    print(status)

To call the mint method of this contract, we send the same CallEngine command with the input parameter containing the method selector - the first 4 bytes of the keccak256 hash of the function signature:

keccak256(‘mint(address,uint256)’) == ‘40c10f19’

concatenated with the function arguments encoded according to the contract ABI rules – the first function argument has the address type, that is a 20-bytes long integer number.

Let’s say the contract owner (the admin@test Iroha account) wants to mint 1000 coins and assign them to himself. To get the EVM address corresponding to the admin@test using Python library we might use:

import sha3
k = sha3.keccak_256()
k.update(b'admin@test')
print(hexlify(k.digest()[12:32]).zfill(64))

That way, we’ll get:

000000000000000000000000f205c4a929072dd6e7fc081c2a78dbc79c76070b

So, the last 20 bytes are keccak256, zero left-padded to 32 bytes.

The amount argument is a uint256 number encoded in hex (also, left-padded):

00000000000000000000000000000000000000000000000000000000000003e8

The entire arguments string is a concatenation of the three pieces above chained together.

Putting it all together, we will get the following client code to call the mint function of the Coin contract:

import os
from iroha import Iroha, IrohaCrypto, IrohaGrpc

iroha = Iroha('admin@test')
net = IrohaGrpc('127.0.0.1:50051')

admin_key = os.getenv(ADMIN_PRIVATE_KEY, IrohaCrypto.private_key())
params = ("40c10f19”                                                          # selector
          "000000000000000000000000f205c4a929072dd6e7fc081c2a78dbc79c76070b"  # address
          "00000000000000000000000000000000000000000000000000000000000003e8"  # amount
         )

tx = iroha.transaction([
    iroha.command('CallEngine', callee='ServiceContract', input=params)
])
IrohaCrypto.sign_transaction(tx, admin_key)

net.send_tx(tx)
for status in net.tx_status_stream(tx):
    print(status)

Calling the send function is done in exactly the same way.

Note the last line of the send function that emits a Sent event which gets recorded in the log as described earlier:

emit Sent(msg.sender, receiver, amount);
Case 2. Interacting with Iroha state

Earlier we looked at an example of a contract that didn’t interact with Iroha state. However, in most real life applications one could imagine running on top of Iroha blockchain (like custom business logic in transaction processing or charging transaction fees etc.) being able to interact with Iroha state is indispensable. In this section we will consider an example of how one can query balances of Iroha accounts (provided the query creator has respective permissions) from inside an EVM smart contract.

Here is a sample code of contact to do so:

contract Iroha {
        address public serviceContractAddress;

        event Created(string indexed name, string indexed domain);
        event Transferred(string indexed source, string indexed destination, string amount);
        event Added(string indexed asset, string amount);


        // Initializing service contract address in constructor
        constructor(){
                serviceContractAddress = 0xA6Abc17819738299B3B2c1CE46d55c74f04E290C;
        }

        // Creates an iroha ccount
        function createAccount(string memory name, string memory domain, string memory key) public  returns (bytes memory result) {
                bytes memory payload = abi.encodeWithSignature(
                        "createAccount(string,string,string)",
                        name,
                        domain,
                        key);
                (bool success, bytes memory ret) = address(serviceContractAddress).delegatecall(payload);
                require(success, "Error calling service contract function");
                emit Created(name, domain);
                result = ret;
        }

        //Transfers asset from one iroha account to another
        function transferAsset(string memory src, string memory dst, string memory asset, string memory description, string memory amount) public returns (bytes memory result) {
                bytes memory payload = abi.encodeWithSignature(
                        "transferAsset(string,string,string,string,string)",
                        src,
                        dst,
                        asset,
                        description,
                        amount);
                (bool success, bytes memory ret) = address(serviceContractAddress).delegatecall(payload);
                require(success, "Error calling service contract function");

                emit Transferred(src, dst, amount);
                result = ret;
        }
        // Adds asset to iroha account
        function addAsset(string memory asset, string memory amount) public returns (bytes memory result) {
                bytes memory payload = abi.encodeWithSignature(
                        "addAsset(string,string)",
                        asset,
                        amount);
                (bool success, bytes memory ret) = address(serviceContractAddress).delegatecall(payload);
                require(success, "Error calling service contract function");

                emit Added(asset, amount);
                result = ret;
        }
        //Queries balance of an iroha account
        function queryBalance(string memory _account, string memory _asset) public returns (bytes memory result) {
                bytes memory payload = abi.encodeWithSignature(
                        "getAssetBalance(string,string)",
                        _account,
                        _asset);
                (bool success, bytes memory ret) = address(serviceContractAddress).delegatecall(payload);
                require(success,"Error calling service contract function ");
                result = ret;
        }
}

In the constructor we initialize the EVM address of the ServiceContract which exposes multiple APIs to interact with Iroha state. These APIs can be used to query as well as modify the Iroha state. Most of the Iroha commands and queries have been integrated. This contract calls the getAssetBalance, createAccount, addAsset and transferAsset methods of the Iroha ServiceContract API.

We need to compile the contract above to get the bytecode using a full-fledged Solidity compiler or the Web-based Remix IDE. Now, we can send transactions from the Python Iroha client to deploy the contract to the EVM and also to call the different functions of the contact. The contract is deployed in a similar manner as shown above. To call a function of the deployed contract, function signature and it’s arguments must be encoded following the ABI-specification.

Here is a sample python code that calls a function of a deployed contract:

def add_asset(address):
        params = get_first_four_bytes_of_keccak(
                b"addAsset(string,string)"
        )
        no_of_param = 2
        for x in range(no_of_param):
                params = params + left_padded_address_of_param(
                        x, no_of_param
                )
        params = params + argument_encoding("coin#test")  # asset id
        params = params + argument_encoding("500")  # amount of asset
        tx = iroha.transaction(
                [
                        iroha.command("CallEngine", caller=ADMIN_ACCOUNT_ID, callee=address, input=params)
                ]
        )
        IrohaCrypto.sign_transaction(tx, ADMIN_PRIVATE_KEY)
        response = net.send_tx(tx)
        for status in net.tx_status_stream(tx):
                print(status)

def make_number_hex_left_padded(number: str, width: int = 64):
        number_hex = "{:x}".format(number)
        return str(number_hex).zfill(width)


def left_padded_address_of_param(param_index: int, number_of_params: int, width: int = 64):
        """Specifies the position of each argument according to Contract ABI specifications."""
        bits_offset = 32 * number_of_params
        bits_per_param = 64
        bits_for_the_param = bits_offset + bits_per_param * param_index
        return make_number_hex_left_padded(bits_for_the_param, width)


def argument_encoding(arg):
        """Encodes the argument according to Contract ABI specifications."""
        encoded_argument = str(hex(len(arg)))[2:].zfill(64)
        encoded_argument = (
                encoded_argument + arg.encode("utf8").hex().ljust(64, "0").upper()
        )
        return encoded_argument


def get_first_four_bytes_of_keccak(function_signature: str):
        """Generates the first 4 bytes of the keccak256 hash of the function signature. """
        k = keccak.new(digest_bits=256)
        k.update(function_signature)
        return k.hexdigest()[:8]

An argument of type string, a dynamic type, is encoded in the following way: First we provide the location part of the argument measured in bytes from the start of the arguments block which is then, left padded to 32 bytes. The data part of the argument starts with the length of the byte array in elements, also left padded to 32 bytes. Then UTF-8 encoding of the string, padded on the right to 32 bytes. This can be achieved with the help of functions in the example.

For more examples and how the code works, you can visit here .

Building Iroha

In this guide we will learn how to install all dependencies, required to build Iroha and how to actually build it.

There will be 3 steps:

  1. Installing environment prerequisites
  2. Installing Iroha dependencies (will be performed automatically for Docker)
  3. Building Iroha

Note

You don’t need to build Iroha to start using it. Instead, you can download prepared Docker image from the Hub, this process explained in details in the Quick Start Guide page of this documentation.

Prerequisites

In order to successfully build Iroha, we need to configure the environment. There are several ways to do it and we will describe all of them.

Currently, we support Unix-like systems (we are basically targeting popular Linux distros and MacOS). If you happen to have Windows or you don’t want to spend time installing all dependencies you might want to consider using Docker environment. Also, Windows users might consider using WSL

Technically Iroha can be built under Windows natively in experimental mode. This guide covers that way too. All the stages related to native Windows build are separated from the main flow due to its significant differences.

Please choose your preferred platform below for a quick access:

Hint

Having troubles? Check FAQ section or communicate to us directly, in case you were stuck on something. We don’t expect this to happen, but some issues with an environment are possible.

Docker

The idea of having up-to-date Docker images is to be able to run Iroha without the need to build it. But now you have the option to run not only the ready-to-use images but also a special Iroha Builder within Docker, to build Iroha the way you would like it.

First of all, you need to install docker and docker-compose. You can read how to install it on the Docker’s website

Note

Please, use the latest available docker daemon and docker-compose.

Iroha Images

You can find all the Iroha Docker Images by searching the Docker Hub or on GitHub.

There are currently the following images:

  • iroha – general build of Iroha 1.x;
  • iroha-burrow – build that has Iroha 1.x with Burrow integration;
  • iroha-ursa – build that has Iroha 1.x with Ursa integration;
  • iroha2 – Iroha 2 build;
  • iroha-builder – a special image that allows you to run an Iroha builder within Docker.

Hint

You can read more on running the images in the Quick Start Guide.

Each image can be used with a respective tag indicating a branch from which the image is built. All the available tags can be found on Docker Hub. Here are all the tags for iroha image.

For example, you can use iroha:develop for the development version of Iroha, or iroha:main for the release version. The same works with all the other images, too.

Iroha Builder

Iroha builder allows you to build Iroha with any of the parameters available for any other platform but to do it conveniently and securely in Docker.

Here are the steps:

  1. First of all, let’s run the builder:
docker run -it hyperledger/iroha-builder:latest

On this step you will start and run the image in a container in an interactive mode. You can use any available tags, default one would be latest, and developmnet tag is develop. Note that you might need to perform some actions with sudo rights.

  1. When you are inside the container, clone Iroha repository:
git clone https://github.com/hyperledger/iroha.git
  1. When Iroha is cloned, go into Iroha folder:
cd iroha
  1. Then run the script that will build all the necessary dependencies via vcpkg:
./vcpkg/build_iroha_deps.sh $PWD/vcpkg-build

Linux

To build Iroha, you will need the following packages:

build-essential git ca-certificates tar ninja-build curl unzip cmake

Use this code to install environment dependencies on Debian-based Linux distro.

apt-get update; \
apt-get -y --no-install-recommends install \
build-essential ninja-build \
git ca-certificates tar curl unzip cmake \
pkg-config zip

Important

If you would like to use Burrow integration you will also need GO. Install it following the instructions on the official website and then use the following command:

go get github.com/golang/protobuf/protoc-gen-go

Note

If you are willing to actively develop Iroha and to build shared libraries, please consider installing the latest release of CMake.

Now you are ready to install Iroha dependencies.

MacOS

If you want to build Iroha from scratch and actively develop it, please use the following code to install all environment dependencies with Homebrew:

xcode-select --install
brew install cmake go pkg-config coreutils ninja git gcc@9

Hint

To install the Homebrew itself please run

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/homebrew/install/master/install)"

Important

If you would like to use Burrow integration you will also need GO. Install it following the instructions on the official website and then use the following command:

go get github.com/golang/protobuf/protoc-gen-go

Now you are ready to install Iroha dependencies.

Windows

Note

All the listed commands are designed for building 64-bit version of Iroha.

Chocolatey Package Manager

First of all you need Chocolatey package manager installed. Please refer the guide for chocolatey installation.

Building the Toolset

Install CMake, Git, Microsoft compilers via chocolatey being in Administrative mode of command prompt:

choco install cmake git visualstudio2019-workload-vctools ninja

PostgreSQL is not a build dependency, but it is recommended to install it now for the testing later:

choco install postgresql
# Don't forget the password you set!

Now you are ready to install Iroha dependencies.

Installing dependencies with Vcpkg Dependency Manager

Currently we use Vcpkg as a dependency manager for all platforms - Linux, Windows and MacOS. We use a fixed version of Vcpkg to ensure the patches we need will work.

That stable version can only be found inside the Iroha repository, so we will need to clone Iroha. The whole process is pretty similar for all platforms but the exact commands are slightly different.

Linux and MacOS

Run in terminal:

git clone https://github.com/hyperledger/iroha.git
cd iroha
./vcpkg/build_iroha_deps.sh $PWD/vcpkg-build

And that is it! You can now move to Building Iroha section.

Windows

Execute from Power Shell:

git clone https://github.com/hyperledger/iroha.git
cd iroha
powershell -ExecutionPolicy ByPass -File .\.packer\win\scripts\vcpkg.ps1 .\vcpkg .\iroha\vcpkg

Great job! You can now move to Building Iroha section.

Note

If you plan to build 32-bit version of Iroha - you will need to install all the mentioned librares above prefixed with x86 term instead of x64.

Build Process

Building Iroha

  1. So, after the dependencies are built, we can start building Iroha itself:
cmake -B build -DCMAKE_TOOLCHAIN_FILE=$PWD/vcpkg-build/scripts/buildsystems/vcpkg.cmake . -DCMAKE_BUILD_TYPE=RELEASE   -GNinja -DUSE_BURROW=OFF -DUSE_URSA=OFF -DTESTING=OFF -DPACKAGE_DEB=OFF

The cmake parameters such as -DUSE_BURROW=ON are exactly the parameters you can choose for your very special build. You can see the full list and description of these parameters here.

  1. Run
cmake --build ./build --target irohad

Warning

If you want to use tests later, instead of building irohad target, you need to use this:

cmake --build ./build --target all
  1. Check the result by running the help:
./build/bin/irohad --help

This step will show you all the parameters. And that is it!

Note

When building on Windows do not execute this from the Power Shell. Better use x64 Native tools command prompt.

Now Iroha is built. Although, if you like, you can build it with additional parameters described below.

If you are content with the results, you can move to the next step and run an Iroha instance.

CMake Parameters

We use CMake to generate platform-dependent build files. It has numerous flags for configuring the final build. Note that besides the listed parameters cmake’s variables can be useful as well. Also as long as this page can be deprecated (or just not complete) you can browse custom flags via cmake -L, cmake-gui, or ccmake.

Hint

You can specify parameters at the cmake configuring stage (e.g cmake -DTESTING=ON).

Main Parameters
Parameter Possible values Default Description
TESTING ON/OFF ON Enables or disables build of the tests
BENCHMARKING OFF Enables or disables build of the Google Benchmarks library
COVERAGE OFF Enables or disables lcov setting for code coverage generation
USE_LIBURSA OFF Enables usage of the HL Ursa cryptography instead of the standard one
USE_BURROW OFF Enables the HL Burrow EVM integration

Note

If you would like to use HL Ursa cryptography for your build, please install Rust in addition to other dependencies. Learn more about HL Ursa integration here.

If you want to use HL Burrow integration, do not forget to first install Go and then protoc-gen-go. Learn more about HL Burrow Integration.

Packaging Specific Parameters
Parameter Possible values Default Description
PACKAGE_ZIP ON/OFF OFF Enables or disables zip packaging
PACKAGE_TGZ OFF Enables or disables tar.gz packaging
PACKAGE_RPM OFF Enables or disables rpm packaging
PACKAGE_DEB OFF Enables or disables deb packaging

Running Tests (optional)

First of all, please make sure you built Iroha correctly for the tests.

After building Iroha, it is a good idea to run tests to check the operability of the daemon. You can run tests with this code:

cmake --build build --target test

Alternatively, you can run the following command in the build folder

cd build
ctest . --output-on-failure

Note

Some of the tests will fail without PostgreSQL storage running, so if you are not using scripts/run-iroha-dev.sh script please run Docker container or create a local connection with following parameters:

docker run --name some-postgres \
-e POSTGRES_USER=postgres \
-e POSTGRES_PASSWORD=mysecretpassword \
-p 5432:5432 \
-d postgres:9.5 \
-c 'max_prepared_transactions=100'

Configure

Configure TLS for client-peer communication (torii)

By default, client-peer communication is not encrypted. To enable it, you need to:

  1. Generate a key/certificate pair for each peer
  2. Distribute the certificate to all clients
  3. Configure irohad to use these keys
  4. [Re]start irohad

Generating keys

Keys must be presented in PEM format. To generate them you can use openssl:

$ openssl genpkey -algorithm rsa -out server.key
$ openssl req -new -key server.key -x509 -out server.crt

You can use any algorithm you want instead of rsa, as long as your openssl supports it. To find out which are supported, you can use

$ openssl list-public-key-algorithms

If you need to use plain IP addresses to connect to the node, you need to specify subjectAltName in your server certificate, for that you need to add a subjectAltName directive to v3_ca section of your openssl config before generating the certificate. For example, for the default installation, /etc/ssl/openssl.cnf:

[ v3_ca ]
subjectAltName=IP:12.34.56.78

Fields in the certificate don’t really matter except for the Common Name (CN), it would be checked against the client’s hostname, and TLS handshake will fail if they do not match (e.g. if you connect to example.com:50051, then irohad at example.com would need to have example.com in common name of the certificate).

Configuring irohad

To configure iroha to use your keys, you need to modify the torii_tls_params config parameter.

It should look like the following block:

"torii_tls_params": {
    "port": 55552,
    "key_pair_path": "/path/to/server"
}

port - set this to any port you would like (but usually you would want 55552)

key_pair_path - set this to full path to the key/certificate pair, such that if you have a key at /path/to/server.key and a certificate at /path/to/server.crt, you need to specify torii_tls_keypair=/path/to/server

Note

In the examples directory there are sample certificates, but to enable TLS you need to have a new certificate for your server (the sample will not work).

PostgreSQL vs. RocksDB

When you use Iroha, you have a choice of building and using it with either PostgreSQL (relational database) or RocksDB (key-value).

Both options are reliable and can be used in production environment but there are some key differences we would like to tell you about that might help you make your choice.

Specific features of PostgreSQL:

  • Classic database option – which means that there are many tools to work with it;
  • When Iroha is working in Docker, PostgreSQL runs in a separate container;
  • With a lot of data PostgreSQL might become slower

Tip

You can learn more about this database in its documentation: https://www.postgresql.org/docs/

Specific features of RocksDB:

  • Fast (see performance testing results);
  • RocksDB is embedded – both WSV and blockstore are in the same database which means more consistency, but there is a possibility of manually adding a hash with access to the database which might cause some security-related concerns;
  • Takes less space on the disk and there is no information that it could grow too big

Tip

You can learn more about this database in its documentation: https://rocksdb.org/docs/getting-started.html

In this section we will understand how to configure Iroha. Some configuration parameters must be the same in all the nodes (they are marked with *) and some can differ. Let’s take a look at example/config.sample

Note

Starting with v1.2 irohad can also be configured via environment variables, not only via config file.

We will start with looking at config file and then look at how Iroha can be configured with environment parameters.

{
  "torii_port": 50051,
  "internal_port": 10001,
  "database": {
     "type": "rocksdb",
     "path": "/path/to/wsv/folder"
  },
  "max_proposal_size": 10,
  "vote_delay": 5000,
  "mst_enable": false,
  "mst_expiration_time": 1440,
  "proposal_creation_timeout": 3000,
  "stale_stream_max_rounds": 2,
  "metrics": "0.0.0.0:7001",
  "healthcheck_port": 50508
}

As you can see, configuration file is a valid json structure. Let’s go line-by-line and understand what every parameter means in configuration file format.

Deployment-specific parameters

  • block_store_path (optional) sets path to the folder where blocks are stored. If this parameter is not specified, blocks will be stored in the database.
  • torii_port sets the port for external communications. Queries and transactions are sent here.
  • internal_port sets the port for internal communications: ordering service, consensus and block loader.
  • database (optional) is used to set the database configuration (see below)
  • pg_opt (optional) is a deprecated way of setting credentials of PostgreSQL: hostname, port, username, password and database name. All data except the database name are mandatory. If database name is not provided, the default one gets used, which is iroha_default.
  • log is an optional parameter controlling log output verbosity and format (see below).
  • utility_service (optional) endpoint for maintenance tasks. If present, must include ip address and port to bind to. See shepherd docs for an example usage of maintenance endpoint.
  • metrics (optional) endpoint to monitor Iroha’s metrics. Prometheus HTTP server listens on this endpoint. If present, must correspond format “[addr]:<port>” and could be for example “127.0.0.1:8080”, “9090”, or “:1234”. Wrong values implicitly disables Prometheus metrics server. There are also cmdline options `--metrics_port and --metrics_addr to override this parameter.
  • healthcheck_port (optional) endpoint for Iroha healthcheck. Sending a request to this endpoint in the form of http://<host>:<healthcheck_port>/healthcheck will return you information about the status of the node: current memory consumption (memory_consumption), current number of blocks (last_block_round), current count of reject rounds (last_reject_round), if the node is syncing information with a remote node at the moment (is_syncing), if the node is currently up (status).

There is also an optional torii_tls_params parameter, which could be included in the config to enable TLS support for client communication.

There, port is the TCP port where the TLS server will be bound, and key_pair_path is the path to the keypair in a format such that appending .crt to it would be the path to the PEM-encoded certificate, and appending .key would be the path to the PEM-encoded private key for this certificate (e.g. if key_pair_path is "/path/to/the/keypair" iroha would look for certificate located at "/path/to/the/keypair.crt" and key located at "/path/to/the/keypair.key")

Warning

Configuration field pg_opt is deprecated, please use database section!

The database section overrides pg_opt when both are provided in configuration.

Both pg_opt and database fields are optional, but at least one must be specified.

The database section fields:

  • host the host to use for PostgreSQL connection
  • port the port to use for PostgreSQL connection
  • user the user to use for PostgreSQL connection
  • password the password to use for PostgreSQL connection
  • working database is the name of database that will be used to store the world state view and optionally blocks.
  • maintenance database is the name of databse that will be used to maintain the working database. For example, when iroha needs to create or drop its working database, it must use another database to connect to PostgreSQL.

Environment-specific parameters

  • max_proposal_size * is the maximum amount of transactions that can be in one proposal, and as a result in a single block as well. So, by changing this value you define the size of potential block. For a starter you can stick to 10. However, we recommend to increase this number if you have a lot of transactions per second.

    This parameter affects performance. Increase this parameter, if your network has a big number of transactions going. If you increase max_proposal_size due to an inreased throughput, you can increase it independently. By increasing this parameter you can improve the performance but note that at some point increasing this value can lead to degradation of the performance.

  • vote_delay * is a waiting time in milliseconds before sending vote to the next peer. Optimal value depends heavily on the amount of Iroha peers in the network (higher amount of nodes requires longer vote_delay). ** We strongly recommend to set it to at least one second - otherwise when some of the peers are not easily reachable, the chain of blocks will grow very slowly or even stop growing.**

    This parameter only affects consensus mechanism. If your network is fast - you are good and this parameter does not effect your network much. But if your network is on a slower side, increase it to give more time for the peers to respond.

  • mst_enable enables or disables multisignature transaction network transport in Iroha. Note that MST engine always works for any peer even when the flag is set to false. The flag only allows sharing information about MST transactions among the peers.

  • mst_expiration_time is an optional parameter specifying the time period in which a not fully signed transaction (or a batch) is considered expired (in minutes). The default value is 1440.

  • proposal_creation_timeout (previously - max_rounds_delay)* is an optional parameter specifying the maximum delay between two consensus rounds (in milliseconds). The default value is 3000. When Iroha is idle, it gradually increases the delay to reduce CPU, network and logging load. However too long delay may be unwanted when first transactions arrive after a long idle time. This parameter allows users to find an optimal value in a tradeoff between resource consumption and the delay of getting back to work after an idle

    This parameter affects resource consumption. When you can expect Iroha to stay idle for longer periods of time and would like to save some resources, increase this value - it will make Iroha check for new transactions more rarely. NB: the first transaction after idle period might be a little delayed due to that. Second and further blocks will be processed quicker.

  • stale_stream_max_rounds is an optional parameter specifying the maximum amount of rounds to keep an open status stream while no status update is reported. The default value is 2. Increasing this value reduces the amount of times a client must reconnect to track a transaction if for some reason it is not updated with new rounds. However large values increase the average number of connected clients during each round.

    It is recommended to limit this parameter to make sure the node is not overloaded with streams.

  • initial_peers is an optional parameter specifying list of peers a node will use after startup instead of peers from genesis block. It could be useful when you add a new node to the network where the most of initial peers may become malicious. Peers list should be provided as a JSON array:

"initial_peers": [
  {
    "address": "127.0.0.1:10001",
    "public_key": "bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308929"
  }
]

Good Practice Example

With even distribution we received quite good results - with 300k transactions sent in 5 minutes. Commit took from 2 seconds to 2 minutes. Please note that results always depend on number of peers in your network, its speed and parameters of the hosts on which the peers run.

Here is the configuration we used:

"max_proposal_size" : 10000,
"vote_delay" : 1000,
"mst_enable" : true,
"mst_expiration_time": 1440,
"proposal_creation_timeout": 500,
"stale_stream_max_rounds": 100000

Environment variables

Another way to configure Iroha is by using environment variables. Configuration file and environment variables can be combined. The parameters specified in the configuration file, if present, will override the ones that are set up through environment.

Here are some examples of how parameters will look like in

Unix

export IROHA_BLOCK_STORE_PATH=/tmp/block_store/
export IROHA_TORII_PORT=50051
export IROHA_INTERNAL_PORT=10001
export IROHA_PG_OPT="host=172.19.0.2 port=5432 user=iroha password=helloworld"
export IROHA_MAX_PROPOSAL_SIZE=10
export IROHA_VOTE_DELAY=5000
export IROHA_MST_ENABLE=false
export IROHA_MST_EXPIRATION_TIME=1440
export IROHA_PROPOSAL_CREATION_TIMEOUT=3000
export IROHA_CRYPTO_PROVIDERS_0_KEY=p1
export IROHA_CRYPTO_PROVIDERS_0_CRYPTO_TYPE=ed25519_sha3_256
export IROHA_CRYPTO_PROVIDERS_0_PRIVATE_KEY=cc5013e43918bd0e5c4d800416c88bed77892ff077929162bb03ead40a745e88
export IROHA_CRYPTO_PROVIDERS_0_TYPE=default
export IROHA_CRYPTO_SIGNER=p1

Windows

setx IROHA_BLOCK_STORE_PATH C:\block_store
setx IROHA_TORII_PORT 50051
setx IROHA_INTERNAL_PORT 10001

PowerShell

$Env:IROHA_BLOCK_STORE_PATH="C:\block_store"
$Env:IROHA_TORII_PORT="50051"
$Env:IROHA_INTERNAL_PORT="10001"

Parameter names

As you can see, the parameter names are not the same as in the configuration file.

They are formed from the config structure, fixed label IROHA is added to the beginning and everything is uppercased and joined with _. Let us look a bit closer at how they are structured:

With simple string values

In configuration file:

"block_store_path": "/tmp/block_store/"

In environment variables:

IROHA_BLOCK_STORE_PATH=/tmp/block_store/

With arrays

Arrays are indexed starting with 0 and should be in direct order without skipping any numbers:

In configuration file:

"initial_peers": [
  {
    "address": "127.0.0.1:10001",
    "public_key": "bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308929"
  },
  {
    "address": "127.0.0.1:10002",
    "public_key": "bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308920"
  }
]

In environment variables:

IROHA_INITIAL_PEERS_0_ADDRESS=127.0.0.1:10001
IROHA_INITIAL_PEERS_0_PUBLIC_KEY=bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308929
IROHA_INITIAL_PEERS_1_ADDRESS=127.0.0.1:10002
IROHA_INITIAL_PEERS_1_PUBLIC_KEY=bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308920

Dictionaries with user-defined keys

User-provided dictionary keys are a bit trickier: the key and the value are set in separate variables. They can be illustrated on the example of configuring cryptography providers:

Crypto providers

Currently, HL Iroha supports one type of provider called default — it includes built-in crypto providers such as HL Iroha crypto library (with crypto type ed25519_sha3_256) and HL Ursa library of which Iroha currently supports crypto type ed25519_sha2_256.

Both of them take only the crypto_type and private_key as parameters.

Note

We are working on adding other types, including hsm — for hardware security modules — they will have a different set of parameters which will be added here after the release.

Configuring crypto providers

To configure currently available crypto providers, you need to define the providers that might be used on the peer (see p1 and p2) and then choose the signer, that will be used to sign messages on this node:

In configuration file:

"crypto": {
  "providers": {
    "p1": {
      "crypto_type": "ed25519_sha3_256",
      "private_key": "cc5013e43918bd0e5c4d800416c88bed77892ff077929162bb03ead40a745e88",
      "type": "default"
    },
    "p2": {
      "crypto_type": "ed25519_sha2_256",
      "private_key": "7bab70e95cb585ea052c3aeb27de0afa9897ba5746276aa1c25310383216ceb860eb82baacbc940e710a40f21f962a3651013b90c23ece31606752f298c38d90",
      "type": "default"
    }
  },
  "signer": "p1"
}

In environment variables:

IROHA_CRYPTO_PROVIDERS_0_KEY=p1
IROHA_CRYPTO_PROVIDERS_0_CRYPTO_TYPE=ed25519_sha3_256
IROHA_CRYPTO_PROVIDERS_0_PRIVATE_KEY=cc5013e43918bd0e5c4d800416c88bed77892ff077929162bb03ead40a745e88
IROHA_CRYPTO_PROVIDERS_0_TYPE=default
IROHA_CRYPTO_PROVIDERS_1_KEY=p2
IROHA_CRYPTO_PROVIDERS_1_CRYPTO_TYPE=ed25519_sha2_256
IROHA_CRYPTO_PROVIDERS_1_PRIVATE_KEY=7bab70e95cb585ea052c3aeb27de0afa9897ba5746276aa1c25310383216ceb860eb82baacbc940e710a40f21f962a3651013b90c23ece31606752f298c38d90
IROHA_CRYPTO_PROVIDERS_1_TYPE=default
IROHA_CRYPTO_SIGNER=p1

Logging

In Iroha logging can be adjusted as granularly as you want. Each component has its own logging configuration with properties inherited from its parent, able to be overridden through config file. This means all the component loggers are organized in a tree with a single root. The relevant section of the configuration file contains the overriding values:

In configuration file:

"log": {
  "level": "trace",
  "patterns": {
    "debug": "don't panic, it's %v.",
    "error": "MAMA MIA! %v!"
  },
  "children": {
    "KeysManager": {
      "level": "trace"
    },
    "Irohad": {
      "children": {
        "Storage": {
          "level": "trace",
          "patterns": {
            "debug": "thread %t: %v."
          }
        }
      }
    }
  }
}

In environment variables:

IROHA_LOG_LEVEL=trace
IROHA_LOG_PATTERNS_0_KEY=debug
IROHA_LOG_PATTERNS_0="don't panic, it's %v."
IROHA_LOG_PATTERNS_1_KEY=error
IROHA_LOG_PATTERNS_1="MAMA MIA! %v!"
IROHA_LOG_CHILDREN_0_KEY=KeysManager
IROHA_LOG_CHILDREN_0_LEVEL=trace
IROHA_LOG_CHILDREN_1_KEY=Irohad
IROHA_LOG_CHILDREN_1_CHILDREN_0_KEY=Storage
IROHA_LOG_CHILDREN_1_CHILDREN_0_LEVEL=trace
IROHA_LOG_CHILDREN_1_CHILDREN_0_PATTERNS_0_KEY=debug
IROHA_LOG_CHILDREN_1_CHILDREN_0_PATTERNS_0="thread %t: %v."

Every part of this config section is optional.

  • level sets the verbosity. Available values are (in decreasing verbosity order):
    • trace - print everything
    • debug
    • info
    • warning
    • error
    • critical - print only critical messages
  • patterns controls the formatting of each log string for different verbosity levels. Each value overrides the less verbose levels too. So in the example above, the “don’t panic” pattern also applies to info and warning levels, and the trace level pattern is the only one that is not initialized in the config (it will be set to default hardcoded value).

Note

Even if multiple patterns are specified for a single component, this component will use only one pattern — the one that corresponds to selected logging level. However, the patterns will be inherited and can be used in the child loggers.

  • children describes the overrides of child nodes. The keys are the names of the components, and the values have the same syntax and semantics as the root log configuration.

Deploy

Hyperledger Iroha can be deployed in different ways, depending on the perspective and the purpose. There can be either a single node deployed, or multiple nodes running in several containers on a local machine or spread across the network — so pick any case you need. This page describes different scenarios and is intended to act as a how-to guide for users, primarily trying out Iroha for the first time.

Security notice

Due to a known issue with gRPC it might not be safe to deploy Iroha in production natively on MacOS or on older versions of Linux.

The issue might cause Iroha to crash due to socket exhaustion and unless it is set up correctly, using, say, Docker, it will need to be restarted manually which might disrupt the work. You can learn more about why the issue affects MacOS and noncontemporary Linux systems in this article (the way gRPC uses polling engine in Mac is susceptible to this type of vulnerability and unlike Linux it cannot be avoided by using other options of polling engines).

So, to be on the safe side, please try to deploy on newer versions of Linux (see the version numbers in the article above) and use Docker with Linux if you prefer MacOS in the production environment.

Running single instance

Generally, people want to run Iroha locally in order to try out the API and explore the capabilities. This can be done in local or container environment (Docker). We will explore both possible cases, but in order to simplify peer components deployment, it is advised to have Docker installed on your machine.

Local environment

By local environment, it is meant to have daemon process and Postgres deployed without any containers. This might be helpful in cases when messing up with Docker is not preferred — generally a quick exploration of the features.

Run postgres server

In order to run postgres server locally, you should check postgres website and follow their description. Generally, postgres server runs automatically when the system starts, but this should be checked in the configuration of the system.

Postgres database server could be initialized and started manually without usual system integration:

Selected port 5433 (default is 5432) and database user iroha_user are used by irohad to connect to database. (see Configuration parameters for more reference). Maintenance database postgres is created by default, but if for some reason another name required, create it:

Run iroha daemon (irohad)

There is a list of preconditions which you should meet before proceeding:

  • Postgres server is up and running
  • irohad Iroha daemon binary is built and accessible in your system
  • The genesis block and configuration files were created
  • Config file uses valid postgres connection settings
  • A keypair for the peer is generated
  • This is the first time you run the Iroha on this peer and you want to create new chain

Hint

Have you got something that is not the same as in the list of assumptions? Please, refer to the section Dealing with troubles.

In case of valid assumptions, the only thing that remains is to launch the daemon process with following parameters:

Parameter Meaning
config configuration file, containing postgres connection and values to tune the system
genesis_block initial block in the ledger
keypair_name private and public key file names without file extension, used by peer to sign the blocks

Attention

Specifying a new genesis block using –genesis_block with blocks already present in ledger requires –overwrite_ledger flag to be set. The daemon will fail otherwise.

An example of shell command, running Iroha daemon is

irohad --config example/config.sample --genesis_block example/genesis.block --keypair_name example/node0

Note

if you are running Iroha built with HL Ursa support please get the example keys and genesis block in example/ursa-keys/

Attention

If you have stopped the daemon and want to use existing chain — you should not pass the genesis block parameter.

Docker

In order to run Iroha peer as a single instance in Docker, you should pull the image for Iroha first:

docker pull hyperledger/iroha:latest

Hint

Use latest tag for latest stable release, and develop for latest development version

Then, you have to create an enviroment for the image to run without problems:

Create docker network

Containers for Postgres and Iroha should run in the same virtual network, in order to be available to each other. Create a network, by typing following command (you can use any name for the network, but in the example, we use iroha-network name):

docker network create iroha-network
Run Postgresql in a container

Similarly, run postgres server, attaching it to the network you have created before, and exposing ports for communication:

docker run --name some-postgres \
-e POSTGRES_USER=postgres \
-e POSTGRES_PASSWORD=mysecretpassword \
-p 5432:5432 \
--network=iroha-network \
-d postgres:9.5
Create volume for block storage

Before we run iroha daemon in the container, we should create persistent volume to store files, storing blocks for the chain. It is done via the following command:

docker volume create blockstore
Running iroha daemon in docker container
There is a list of assumptions which you should review before proceeding:
  • Postgres server is running on the same docker network
  • There is a folder, containing config file and keypair for a single node
  • This is the first time you run the Iroha on this peer and you want to create new chain

If they are met, you can move forward with the following command:

docker run --name iroha \
# External port
-p 50051:50051 \
# Folder with configuration files
-v ~/Developer/iroha/example:/opt/iroha_data \
# Blockstore volume
-v blockstore:/tmp/block_store \
# Postgres settings
-e POSTGRES_HOST='some-postgres' \
-e POSTGRES_PORT='5432' \
-e POSTGRES_PASSWORD='mysecretpassword' \
-e POSTGRES_USER='postgres' \
# Node keypair name
-e KEY='node0' \
# Docker network name
--network=iroha-network \
hyperledger/iroha:latest

irohad Flags

You can start irohad with different flags. Some of the main ones were already mentioned but there are others, that you might find useful for your unique situation. Here they are:

Flag Description Type Default
-config specifies Iroha provisioning path string “”
-drop_state drops existing state data at startup bool false
-genesis_block specifies file with initial block string “”
-keypair_name specifies name of .pub and .priv files string “”
-metrics_addr Prometeus HTTP server listen address string “127.0.0.1”
-metrics_port Prometeus HTTP server listens port, disabled by default string “”
-overwrite_ledger overwrites ledger data if existing bool false
-reuse_state tries to reuse existing state data at startup (Deprecated, startup reuses state by default. Use drop_state to drop the WSV) bool true
-verbosity log verbosity string “config_file”
-wait_for_new_blocks startup synchronization policy - waits for new blocks in blockstore, does not run network bool false

Running multiple instances (peer network)

In order to set up a peer network, one should follow routines, described in this section. In this version, we support manual deployment and automated by Ansible Playbook. Choose an option, that meets your security criteria and other needs.

Manually

By manual deployment, we mean that Iroha peer network is set up without automated assistance. It is similar to the process of running a single local instance, although the difference is the genesis block includes more than a single peer. In order to form a block, which includes more than a single peer, or requires customization for your needs, please take a look at :ref:`deploy_troubles section.

Automated

iroha-swarm produces configuration files for docker-compose to spawn a number of Iroha nodes in a one command-line. You can select database type – RocksDB or Postgres, – provide peer keys or use pregenerated ones. Very convenient for basic/first config file generation and for regularly changed environment (different sets of nodes).

Here is also a guide that might be outdated but could provide some helpful information.

Deploying Iroha on Kubernetes cluster

Warning

Some parts of this guide are deprecated. Proceed at your own discretion.

By following this guide you will be able to deploy a Kubernetes cluster from scratch on AWS cloud using Terraform and Kubespray, and deploy a network of Iroha nodes on it.

Prerequisites

  • machine running Linux (tested on Ubuntu 16.04) or MacOS
  • Python 3.3+
  • boto3
  • Ansible 2.4+
  • ed25519-cli utility for key generation. Statically linked binary (for x86_64 platform) can be found in deploy/ansible/playbooks/iroha-k8s/scripts directory. You may need to compile it yourself.

You do not need the items below if you already have a working Kubernetes (k8s) cluster. You can skip to Generating Iroha configs chapter.

  • Terraform 0.11.8+
  • AWS account for deploying a k8s cluster on EC2

Preparation

You need to obtain AWS key for managing resources. We recommend to create a separate IAM user for that. Go to your AWS console, head to “My Security Credentials” menu and create a user in “Users” section. Assign “AmazonEC2FullAccess” and “AmazonVPCFullAccess” policies to that user. Click “Create access key” on Security credentials tab. Take a note for values of Access key ID and Secret key. Set these values as environment variables in your console:

export AWS_ACCESS_KEY_ID='<The value of Access key ID>'
export AWS_SECRET_ACCESS_KEY='<The value of Secret key>'

Checkout the source tree from Github:

git clone https://github.com/hyperledger/iroha && cd iroha

Setting up cloud infrastructure

We use Hashicorp’s Terraform infrastructure management tool for automated deployment of AWS EC2 nodes in multiple regions. Kubespray Ansible module is used for setting up a production-grade k8s cluster.

Terraform module creates 3 AWS instances in 3 different regions: eu-west-1, eu-west-2, eu-west-3 by default. Instance type is c5.large. There is a separate VPC created in every region. All created VPCs are then connected using VPC peering connection. That is to create a seamless network for k8s cluster.

There are several configurable options: number of nodes in each region and its role in k8s cluster (kube-master or kube-node). They can be set either in variables.tf file or via environment variables (using the same variable name but prefixed with TF_VAR. See more in Terraform docs). More options can be configured by tuning parameters in module’s variables.tf file.

You must set up SSH key in deploy/tf/k8s/variables.tf as well. Replace public key with your own. It will added on each created EC2 instance.

Navigate to deploy/tf/k8s directory. Terraform needs to download required modules first:

pushd deploy/tf/k8s && terraform init

Then run module execution:

terraform apply && popd

Review the execution plan and type yes to approve. Upon completion you should see an output similar to this:

Apply complete! Resources: 39 added, 0 changed, 0 destroyed.

We are now ready to deploy k8s cluster. Wait a couple of minutes before instances are initialized.

Setting up k8s cluster

There is an Ansible role for setting up k8s cluster. It is an external module called Kubespray. It is stored as a submodule in Hyperledger Iroha repository. This means it needs to be initialized first:

git submodule init && git submodule update

This command will download Kubespray from master repository.

Install required dependencies:

pip3 install -r deploy/ansible/kubespray/requirements.txt

Proceed to actual cluster deployment. Make sure you replaced key-file parameter with an actual path to SSH private key that was used previously during Terraform configuration. REGIONS variable corresponds to default list of regions used on a previous step. Modify it accordingly in case you added or removed any. Inventory file is a Python script that returns Ansible-compatible list of hosts filtered by tag.

pushd deploy/ansible && REGIONS="eu-west-1,eu-west-2,eu-west-3" VPC_VISIBILITY="public" ansible-playbook -u ubuntu -b --ssh-extra-args="-o IdentitiesOnly=yes" --key-file=<PATH_TO_SSH_KEY> -i inventory/kubespray-aws-inventory.py kubespray/cluster.yml
popd

Upon successful completion you will have working k8s cluster.

Generating Iroha configs

In order for Iroha to work properly it requires to generate a key pair for each node, genesis block and configuration file. This is usually a tedious and error-prone procedure, especially for a large number of nodes. We automated it with Ansible role. You can skip to Deploying Iroha on the cluster chapter if you want to quick start using default configs for k8s cluster with 4 Iroha replicas.

Generate configuration files for N Iroha nodes. replicas variable controls the number of N:

pushd deploy/ansible && ansible-playbook -e 'replicas=7' playbooks/iroha-k8s/iroha-deploy.yml
popd

You should find files created in deploy/ansible/roles/iroha-k8s/files/conf.

Deploying Iroha on the cluster

Make sure you have configuration files in deploy/ansible/roles/iroha-k8s/files. Specifically, non-empty conf directory and k8s-iroha.yaml file.

There are two options for managing k8s cluster: logging into either of master node and executing commands there or configure remote management. We will cover the second option here as the first one is trivial.

In case you set up cluster using Kubespray, you can find admin.conf file on either of master node in /etc/kubernetes directory. Copy this file on the control machine (the one you will be running kubectl command from). Make sure server parameter in this file points to external IP address or DNS name of a master node. Usually, there is a private IP address of the node (in case of AWS). Make sure kubectl utility is installed (check out the docs for instructions).

Replace the default kubectl configuration:

export KUBECONFIG=<PATH_TO_admin.conf>

We can now control the remote k8s cluster

k8s-iroha.yaml pod specification file requires the creation of a config-map first. This is a special resource that is mounted in the init container of each pod, and contains the configuration and genesis block files required to run Iroha.

kubectl create configmap iroha-config --from-file=deploy/ansible/roles/iroha-k8s/files/conf/

Each peer will have their public and private keys stored in a Kubernetes secret which is mounted in the init container and copied over for Iroha to use. Peers will only be able read their assigned secret when running Iroha.

kubectl create -f deploy/ansible/roles/iroha-k8s/files/k8s-peer-keys.yaml

Deploy Iroha network pod specification:

kubectl create -f deploy/ansible/roles/iroha-k8s/files/k8s-iroha.yaml

Wait a moment before each node downloads and starts Docker containers. Executing kubectl get pods command should eventually return a list of deployed pods each in Running state.

Hint

Pods do not expose ports externally. You need to connect to Iroha instance by its hostname (iroha-0, iroha-1, etc). For that you have to have a running pod in the same network.

Dealing with troubles

—”Please, help me, because I…”

Do not have Iroha daemon binary

You can build Iroha daemon binary from sources. You can get binaries here

Do not have a config file

Check how to create a configuration file by following this link

Do not have a genesis block

Create genesis block by generating it via iroha-cli or manually, using the example and checking out permissions

Do not have a keypair for a peer

In order to create a keypair for an account or a peer, use iroha-cli binary by passing the name of the peer with –new_account option. For example:

./iroha-cli --account_name newuser@test --new_account

Maintain

Hardware requirements, deployment process in details, aspects related to security, configuration files — all of the listed is explained in this separate section, helpful for DevOps engineers or those who are digging deeper in the system capabilities.

Adding Peers

In HL Iroha, you can add new peers to the network while it is running. This is done by using a special command, AddPeer.

Requirements

There should be a peer that:

— runs with a Genesis Block (initial block of the blockchain) identical to the one on the peers already in the network;

— has a resolvable address;

— has a peer keypair (Ed25519 with SHA-2/SHA-3)

Important

The account that is sending the transaction adding a peer must have the Can Add Peer permission and to remove a peer —Can Remove Peer permission in their role - this must be set in the genesis block.

Usage

As described in the API reference to use the command, you will only need:

— a public key of the peer that you want to add to the network;

— resolvable IP address of the peer

Steps:

  1. Create a network with Can Add Peer and Can Remove Peer permissions set up in the genesis block assigned to a user;
  2. Create another peer running HL Iroha with the same genesis block and similar configuration;
  3. Send a transaction from the account with the necessary permissions that has add peer command in it (see an example below)
  4. Check the logs of the peers to see if everything is working correctly.

You can also make sure the everything is ok by sending a transaction and checking if the number of blocks is the same on the nodes.

Note

If there are only 1 existing peer running, you will need to configure the peers that you are adding so that they would have all of the peers (both already existing and the new ones) in the “initial_peers” parameter in the configuration. Another case when this is needed is when the network has been running for some time and the peers indicated in the genesis block are no longer there (because they were removed using Remove Peer command while new peers were added).

Example

Here is what a command might look like in Python. In this example we used Root permission that has all permissions, including Can Add Peer permission and Can Remove Peer permission:

def add_peer():
    peer1 = primitive_pb2.Peer()
    peer1.address = '192.168.1.1:50541'
    peer1.peer_key = '716fe505f69f18511a1b083915aa9ff73ef36e6688199f3959750db38b8f4bfc'
    tx = iroha.transaction([
        iroha.command('AddPeer', peer=peer1)
    ], creator_account=ADMIN_ACCOUNT_ID, quorum=1)

    IrohaCrypto.sign_transaction(tx, ADMIN_PRIVATE_KEY)

add_peer()

Remove Peer

To remove the peer, you will need to use Remove Peer command from the account that has CanRemovePeer permission.

Restarting Iroha node with existing WSV

Previously, in cases when you had to update a node or it shut down for some reason, there was only one option of re-reading all of the blocks to recreate consistent world state view (aka WSV). To start up a node quicker, it is now possible to reuse an existing WSV database after a quick check. For that, hash of the top block and the height of the blockstorage are included in the WSV.

Warning

It is up to Administrators of the node to make sure the WSV is not edited manually – only by Iroha or the migration script. Manual editing or editing of the migration script not following a trustworthy guideline can lead to inconsistent network. Only do so at your own risk (we warned you).

Although it can be a great idea for some of the cases, but please consider that there are certain specifics of reusing WSV, compared to restoring it from blockstorage:

Trust point
Reusing WSV: we need to rely on both blockstorage and WSV.
Restore WSV from block storage: we trust only the genesis block.
Integrity
Reusing WSV: blockstorage and WSV must match each other! Iroha will not check for that.
Restore WSV from block storage: Iroha will check every block, while restoring WSV. Any error in blockstorage will be found (except genesis block, of course). WSV is guaranteed to match the blockstorage.
Time
Reusing WSV: Iroha is almost immediately ready to operate in the network.
Restore WSV from block storage: the larger blockstorage - the longer it takes to restore it and begin operation.

Note

If the local ledger that shut down has more blocks than it should and the correct WSV is among them - it is ok, Iroha will take the WSV of the correct block. If blocks are less than should be – the option of reusing WSV will not work for you. Please, restore it from blocks.

Dropping WSV

By default Iroha reuses WSV state on startup, so there is no need in –reuse_state flag anymore. However, it is left for backward compatibility. If you want to drop WSV state, start Iroha with ‘–drop_state’ flag. Given this flag, Iroha will reset and overwrite the state database.

State Database Schema version

When reusing existing WSV, Iroha performs a schema version compatibility check. It will not start or somehow alter the database, if its schema is not compatible with the Iroha in use.

If your schema was created by Iroha of version v1.1.1 or lower, most likely it does not include the version information. In this case you need to add it manually. You are encouraged to use our script for this purpose, it is located here. To forcefully (i.e. without any migration process) set your schema version, launch the script with –force_schema_version flag and pass the version of Iroha binary that was used to create your schema.

Warning

Before forcefully writing the schema version numbers, double check the version of irohad that created the schema. No checks are performed when you force schema numbers, hence it is easy to break the state database in the future (during the next migration).

Changing Iroha version. Migration.

In case you want to change Iroha version while keeping the WSV, you are encouraged to perform a migration. Although it might be unnecessary (Iroha will refuse to start if the schema is incompatible), as a general rule, we improve the schema with each version and migration might be a good idea for a better performance. You are encouraged to perform a database backup before migration using standard PostgreSQL guidelines for that.

To perform migration, please use our script.

It will load the schema information from the database and match it with migration steps (by default, migration scenarios are defined in migration_data directory in the same folder as the script). Then it will find all migration paths that will transition your database to the desired version and ask you to choose one.

See also

Here are some details about different migration cases and examples you can check out to perform migration

Synchronize WSV mode.

Specify ‘–wait_for_new_blocks’ options for WSV synchronization mode. Iroha restores WSV from blockstore and waits for new blocks to be added externally. In this mode Iroha will not perform network operations.

Iroha installation security tips

This guide is intended to secure Iroha installation. Most of the steps from this guide may seem obvious but it helps to avoid possible security problems in the future.

Physical security

In case the servers are located locally (physically accessible), a number of security measures have to be applied. Skip these steps if cloud hosting is used.

Establish organisational policy and/or access control system such that only authorized personnel has access to the server room. Next, set BIOS/firmware password and configure boot order to prevent unauthorized booting from alternate media. Make sure the bootloader is password protected if there is such a functionality. Also, it is good to have a CCTV monitoring in place.

Deployment

First, verify that official repository is used for downloading source code and Docker images. Change any default passwords that are used during installation, e.g., password for connecting to postgres. Iroha repository contains examples of private and public keys - never use it in production. Moreover, verify that new keypairs are generated in a safe environment and only administrator has access to those keypairs (or at least minimise the number of people). After deploying keys to Iroha peers delete private keys from the host that was used to perform deployment, i.e. private keys should reside only inside Iroha peers. Create an encrypted backup of private keys before deleting them and limit the access to it.

Network configuration

Iroha listens on ports 50051 and 10001, and optionally 55552, if TLS is enabled. Firewall settings must allow incoming/outgoing connections to/from these ports. If possible, disable or remove any other network services with listening ports (FTP, DNS, LDAP, SMB, DHCP, NFS, SNMP, etc). Ideally, Iroha should be as much isolated as possible in terms of networking.

You can enable TLS on torii ports if you would like to encrypt client-peer communication.

If you don’t use traffic encryption, we strongly recommend using VPN or Calico for setting up Docker overlay network, i.e. any mechanism that allows encrypting communication between peers. Docker swarm encrypts communications by default, but remember to open necessary ports in the firewall configuration. In case VPN is used, verify that VPN key is unavailable to other users.

If SSH is used, disable root login. Apart from that, disable password authentication and use only keys. It might be helpful to set up SSH log level to INFO as well.

If IPv6 is not used, it might be a good idea to disable it.

Updates

Install the latest operating system security patches and update it regularly. If Iroha is running in Docker containers, update Docker regularly. While being optional, it is considered a good practice to test updates on a separate server before installing to production.

Logging and monitoring

  • Collect and ship logs to a dedicated machine using an agent (e.g., Filebeat).
  • Collect logs from all Iroha peers in a central point (e.g., Logstash).
  • Transfer logging and monitoring information via an encrypted channel (e.g., https).
  • Set up an authentication mechanism to prevent third parties from accessing logs.
  • Set up an authentication mechanism to prevent third parties from submitting logs.
  • Log all administrator access.

OS hardening

The following steps assume Docker is used for running Iroha.

  • Enable and configure Docker Content Trust.
  • Allow only trusted users to control Docker daemon.
  • Set up a limit for Docker container resources.

Shepherd

Shepherd is a command line utility that helps to perform maintenance tasks with running irohad daemon.

Prerequisites

To access irohad daemon, utility service has to be configured in it. See the configuration details.

Next, when invoking shepherd, pass the --irohad command line argument with address and port of irohad utility service:

./shepherd --irohad 127.0.0.1:11001 <...>

Supported actions

These are the things that you can do with shepherd by specifying additional command line arguments.

Graceful shutdown

How did you stop iroha before? What, did you really really kill it? Oh, please never do that again, it is not polite and nice!

./shepherd <...> --shutdown

With --shutdown argument, shepherd will politely ask Iroha to stop.

Watch it work

Widely considered one of the greatest pleasures is watching others work. With shepherd you can watch Iroha working!

./shepherd <...> --status

This will subscribe for work cycle status updates. You will get unambiguous messages when the daemon is starting, operating, terminating or has just stopped.

Other parameters

You can also set the logging level:

./shepherd <...> --verbosity debug <...>

Supported values are trace, debug, info, warning, error and critical.

Troubleshooting

Restore after hard shutdown

[2020-11-27 10:40:01.764013860][th:1][warning] Irohad/Storage/FlatFileBlockStorage Error while block deserialization: Unexpected end of string. Expected a value.

^
[2020-11-25 10:36:19.993552669][C][Init]: Irohad startup failed: WSV state (height 4576773) is more recent than block storage (height 4576772).

Such messages may appear if the node crashed while using file-based block store. Please copy the missing blocks from another node, in which case you can use --reuse_state flag for fast startup, or remove the blocks starting from the empty file and recreate WSV from existing blocks.

Metrics

To conveniently and thoroughly monitor the performance of the network, you can now use metrics. It is numeric data collected over time about your Iroha network. You can then analyse the data to make your project even more efficient!

How to use metrics?

To use metrics, you need to add it to your Iroha configuration and use Iroha version that is newer than 1.2.1.

Note

If you are running Iroha in Docker, to access metrics from outside the countainer you will need to: 1) In config – set up "metrics":0.0.0.0:PORT; 2) Expose corresponding port in Docker while executing run ... -pPORT:PORT ...

Then, you can simply use the ip address to access the data from the running Iroha instance.

Here is an example:

> curl http://127.0.0.1:8080/metrics

will give you results like:

# HELP blocks_height Total number of blocks in chain
# TYPE blocks_height gauge
blocks_height 135543
# HELP peers_number Total number peers to send transactions and request proposals
# TYPE peers_number gauge
peers_number 7
# HELP number_of_domains Total number of domains in WSV
# TYPE number_of_domains gauge
number_of_domains 14
# HELP total_number_of_transactions Total number of transactions in blockchain
# TYPE total_number_of_transactions gauge
total_number_of_transactions 216499
# HELP number_of_signatures_in_last_block Number of signatures in last block
# TYPE number_of_signatures_in_last_block gauge
number_of_signatures_in_last_block 5

Migration To RocksDB

Iroha allows for using Postgres or Rocks Database. You can use the option you prefer and if you want to switch – there is an option for you. Just migrate your database! Here is how

Hint

Both migration tool and WSV checker have -help that you can call to check the available flags anytime.

How to migrate

After you built Iroha (or simply pull the Docker image) version 1.3 (or later) you already have the migration tools as a separate executable! By default, after building, Iroha stores binaries to BUILD_DIR/bin/.

Just run the iroha_migrate with the following flags:

  • -help - help
  • -block_store_path - specifies path to block store. Default: “/tmp/block_store”
  • -export - exports block store to specified directory, default – current working directory (CWD). Use it to reverse migration to RocksDB (by exporting files from it).
  • -drop_state - use it to override blocks in RocksDB blockstore if it already exists. This might be very useful if the next step - checking the correctness of the migrated database - goes through with errors and you need to repeat the migration process. Default: false
  • -rocksdb_path - specifies the path to RocksDB. Default: “rocks.db”
In case of success you will see this message
Success! WSV in RocksDB was build.
Next step check consintancy with Postgres WSV using iroha_wsv_diff.

If migration fails, it will exit with non-zero code. In this case, please check all the flags and try again.

And… your database is migrated! But that is not all.

To make sure that your migration process has been successful, please then use the WSV check.

How to check WSV after the migration

Run iroha_wsv_diff with the following flags:

  • -help - help
  • -pg_opt - specifies Postgres options line. It should be as in your configuration. Default: “dbname=iroha_default host=localhost port=5432 user=postgres password=postgres”
  • -rocksdb_path - specifies path to the RocksDB. Default: “rocks.db”

If the databases are the same, you will see Mr. Spock. Also, (if you are not much of a sci-fi fan) the exit code will be zero.

Successful check will result in something like this
Reading rocksdb... in 7112ms
     Reading postgres... in 5923ms
     See detailed dumps in files rockdb.wsv and postgres.wsv
     == VALIDATING ==
     left is rocksdb, right is postgres
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     ~~~ WSV-s are same. Enjoy Iroha with RocksDB ~~~

If not, there will be the differences in the databases: the data on the left is what is indicated in the RocksDB and on the right – what is in Postgres.

Failed check will result in something like this
Reading rocksdb... in 6990ms
Reading postgres... in 5652ms
See detailed dumps in files rockdb.wsv and postgres.wsv
== VALIDATING ==
left is rocksdb, right is postgres
Role-s 'client' have different permissions: '00000000000001110100100100000100100100011010111010000' and '00000000000001110100100100000100100100011010111010011'
Wsv-s have different roles.
AssetQuantity-s 'test#test' have different quantity: '0.0' and '1234567.0'
Accounts 'superuser@bootstrap' have different assetsquantity
Domains 'bootstrap' have different accounts.
Wsv-s have different domains.
~~~ WSV-s DIFFER!!! ~~~
For future investigation use difftool on files rocksdb.wsv and postgres.wsv. Just like:
        diff <(tail -n+2 postgres.wsv) <(tail -n+2 rockdb.wsv)

If there are differences, we would suggest to use the migration tool again with the -drop_state flag.

In case of discrepancies, the command will exit with a non-zero code. Differences will be reported to the console and full WSVs of both DBs will be dumped to corresponding files (the output in the form of postgres.wsv and rocksdb.wsv will be in the current working directory (CWD)). For future investigation you can use any diff tool to see the exact differences between WSVs.

Good Migration Practices

Iroha maintainers often receive questions about the best ways to migrate projects to new versions of Iroha, so we decided to share our practices that worked the best for us and our projects.

On an example of a 4 peer network we will go through a migration procedure (also moving from PostgeSQL database to RocksDB) that turned out to be the most stable and reliable in our projects.

Here are the steps:

  1. You have the 4 nodes running Iroha with the old version on Postgres
  2. Follow the instructions on Iroha Database migration. Copy the RocksDB folder. Skip this step if you do not need to switch between Postgres and RocksDB
  3. Add a new peer running the new version of Iroha using the Add Peer command and with the RocksDB folder on it.
  4. Add similar nodes 2 more times
  5. Now you have 7 nodes – 4 running the old version and 3 running the new one
  6. Switch off the first node with the old version and update this node with the same key pair to the new version (with RocksDB, if that is your goal)
  7. Repeat this for every node with the old Iroha version
  8. Now you can remove the “new” nodes and continue the work on your project!

Develop on Iroha

Iroha is a great backend for your applications working on distributed ledgers. In this section we will cover the instruments (API reference and libraries) and cases you could use for that.

You can also check out The Borsello App – it is a wallet for Android & iOS along with a web browser application contributed by Claudio. It might help you understand the general idea of how frontend can be used with HL Iroha. You can also check out the sample web javascript wallet developed in Vue.

Client Libraries

Java Library

Client library of Iroha written completely in Java 8, which includes:

  • SDK to work with Iroha API
  • async wrapper over Iroha API
  • testcontainers wrapper for convenient integration testing with Iroha
  • examples in Java and Groovy

Both options are described in the following sections. Please check readme file in project’s repo.

How to use
Example code
import iroha.protocol.BlockOuterClass;
import iroha.protocol.Primitive.RolePermission;
import java.math.BigDecimal;
import java.security.KeyPair;
import java.util.Arrays;
import jp.co.soramitsu.crypto.ed25519.Ed25519Sha3;
import jp.co.soramitsu.iroha.testcontainers.IrohaContainer;
import jp.co.soramitsu.iroha.testcontainers.PeerConfig;
import jp.co.soramitsu.iroha.testcontainers.detail.GenesisBlockBuilder;
import lombok.val;

public class Example1 {

  private static final String bankDomain = "bank";
  private static final String userRole = "user";
  private static final String usdName = "usd";

  private static final Ed25519Sha3 crypto = new Ed25519Sha3();

  private static final KeyPair peerKeypair = crypto.generateKeypair();

  private static final KeyPair useraKeypair = crypto.generateKeypair();
  private static final KeyPair userbKeypair = crypto.generateKeypair();

  private static String user(String name) {
    return String.format("%s@%s", name, bankDomain);
  }

  private static final String usd = String.format("%s#%s", usdName, bankDomain);

  /**
   * <pre>
   * Our initial state cosists of:
   * - domain "bank", with default role "user" - can transfer assets and can query their amount
   * - asset usd#bank with precision 2
   * - user_a@bank, which has 100 usd
   * - user_b@bank, which has 0 usd
   * </pre>
   */
  private static BlockOuterClass.Block getGenesisBlock() {
    return new GenesisBlockBuilder()
        // first transaction
        .addTransaction(
            // transactions in genesis block can have no creator
            Transaction.builder(null)
                // by default peer is listening on port 10001
                .addPeer("0.0.0.0:10001", peerKeypair.getPublic())
                // create default "user" role
                .createRole(userRole,
                    Arrays.asList(
                        RolePermission.can_transfer,
                        RolePermission.can_get_my_acc_ast,
                        RolePermission.can_get_my_txs,
                        RolePermission.can_receive
                    )
                )
                .createDomain(bankDomain, userRole)
                // create user A
                .createAccount("user_a", bankDomain, useraKeypair.getPublic())
                // create user B
                .createAccount("user_b", bankDomain, userbKeypair.getPublic())
                // create usd#bank with precision 2
                .createAsset(usdName, bankDomain, 2)
                // transactions in genesis block can be unsigned
                .build() // returns ipj model Transaction
                .build() // returns unsigned protobuf Transaction
        )
        // we want to increase user_a balance by 100 usd
        .addTransaction(
            Transaction.builder(user("user_a"))
                .addAssetQuantity(usd, new BigDecimal("100"))
                .build()
                .build()
        )
        .build();
  }

  public static PeerConfig getPeerConfig() {
    PeerConfig config = PeerConfig.builder()
        .genesisBlock(getGenesisBlock())
        .build();

    // don't forget to add peer keypair to config
    config.withPeerKeyPair(peerKeypair);

    return config;
  }

  /**
   * Custom facade over GRPC Query
   */
  public static int getBalance(IrohaAPI api, String userId, KeyPair keyPair) {
    // build protobuf query, sign it
    val q = Query.builder(userId, 1)
        .getAccountAssets(userId)
        .buildSigned(keyPair);

    // execute query, get response
    val res = api.query(q);

    // get list of assets from our response
    val assets = res.getAccountAssetsResponse().getAccountAssetsList();

    // find usd asset
    val assetUsdOptional = assets
        .stream()
        .filter(a -> a.getAssetId().equals(usd))
        .findFirst();

    // numbers are small, so we use int here for simplicity
    return assetUsdOptional
        .map(a -> Integer.parseInt(a.getBalance()))
        .orElse(0);
  }

  public static void main(String[] args) {
    // for simplicity, we will create Iroha peer in place
    IrohaContainer iroha = new IrohaContainer()
        .withPeerConfig(getPeerConfig());

    // start the peer. blocking call
    iroha.start();

    // create API wrapper
    IrohaAPI api = new IrohaAPI(iroha.getToriiAddress());

    // transfer 100 usd from user_a to user_b
    val tx = Transaction.builder("user_a@bank")
        .transferAsset("user_a@bank", "user_b@bank", usd, "For pizza", "10")
        .sign(useraKeypair)
        .build();

    // create transaction observer
    // here you can specify any kind of handlers on transaction statuses
    val observer = TransactionStatusObserver.builder()
        // executed when stateless or stateful validation is failed
        .onTransactionFailed(t -> System.out.println(String.format(
            "transaction %s failed with msg: %s",
            t.getTxHash(),
            t.getErrOrCmdName()
        )))
        // executed when got any exception in handlers or grpc
        .onError(e -> System.out.println("Failed with exception: " + e))
        // executed when we receive "committed" status
        .onTransactionCommitted((t) -> System.out.println("Committed :)"))
        // executed when transfer is complete (failed or succeed) and observable is closed
        .onComplete(() -> System.out.println("Complete"))
        .build();

    // blocking send.
    // use .subscribe() for async sending
    api.transaction(tx)
        .blockingSubscribe(observer);

    /// now lets query balances
    val balanceUserA = getBalance(api, user("user_a"), useraKeypair);
    val balanceUserB = getBalance(api, user("user_b"), userbKeypair);

    // ensure we got correct balances
    assert balanceUserA == 90;
    assert balanceUserB == 10;
  }
}

Javascript library

https://img.shields.io/npm/v/iroha-helpers.svg

This library provides functions which will help you to interact with Hyperledger Iroha from your JS program.

Installation

Via npm

$ npm i iroha-helpers

Via yarn

$ yarn add iroha-helpers
Commands

For usage of any command you need to provide commandOptions as a first argument.

const commandOptions = {
  privateKeys: ['f101537e319568c765b2cc89698325604991dca57b9716b58016b253506cab70'], // Array of private keys in hex format
  creatorAccountId: '', // Account id, ex. admin@test
  quorum: 1,
  commandService: null
}

As second argument you need to provide object that contains properties for required command.

// Example usage of setAccountDetail

const commandService = new CommandService_v1Client(
  '127.0.0.1:50051',
  grpc.credentials.createInsecure()
)

const adminPriv = 'f101537e319568c765b2cc89698325604991dca57b9716b58016b253506cab70'

commands.setAccountDetail({
  privateKeys: [adminPriv],
  creatorAccountId: 'admin@test',
  quorum: 1,
  commandService
}, {
  accountId: 'admin@test',
  key: 'jason',
  value: 'statham'
})
Queries

For usage of any query you need to provide queryOptions as a first argument.

const queryOptions = {
  privateKey: 'f101537e319568c765b2cc89698325604991dca57b9716b58016b253506cab70', // Private key in hex format
  creatorAccountId: '', // Account id, ex. admin@test
  queryService: null
}

As second argument you need to provide object that contains properties for required query.

// Example usage of getAccountDetail

const queryService = new QueryService_v1Client(
  '127.0.0.1:50051',
  grpc.credentials.createInsecure()
)

const adminPriv = 'f101537e319568c765b2cc89698325604991dca57b9716b58016b253506cab70'

queries.getAccountDetail({
  privateKey: adminPriv,
  creatorAccountId: 'admin@test',
  queryService
}, {
  accountId: 'admin@test'
})
Example code
import grpc from 'grpc'
import {
  QueryService_v1Client,
  CommandService_v1Client
} from '../iroha-helpers/lib/proto/endpoint_grpc_pb'
import { commands, queries } from 'iroha-helpers'

const IROHA_ADDRESS = 'localhost:50051'
const adminPriv =
  'f101537e319568c765b2cc89698325604991dca57b9716b58016b253506cab70'

const commandService = new CommandService_v1Client(
  IROHA_ADDRESS,
  grpc.credentials.createInsecure()
)

const queryService = new QueryService_v1Client(
  IROHA_ADDRESS,
  grpc.credentials.createInsecure()
)

Promise.all([
  commands.setAccountDetail({
    privateKeys: [adminPriv],
    creatorAccountId: 'admin@test',
    quorum: 1,
    commandService
  }, {
    accountId: 'admin@test',
    key: 'jason',
    value: 'statham'
  }),
  queries.getAccountDetail({
    privateKey: adminPriv,
    creatorAccountId: 'admin@test',
    queryService
  }, {
    accountId: 'admin@test'
  })
])
  .then(a => console.log(a))
  .catch(e => console.error(e))

Python Library

Where to Get

A supported python library for Iroha is available at its own Hyperledger iroha-python repo. Python 3+ is supported.

You can also install Python library via pip:

pip install iroha
Example Code
from iroha import Iroha, IrohaCrypto, IrohaGrpc

iroha = Iroha('alice@test')
net = IrohaGrpc('127.0.0.1:50051')

alice_key = IrohaCrypto.private_key()
alice_tx = iroha.transaction(
 [iroha.command(
     'TransferAsset',
     src_account_id='alice@test',
     dest_account_id='bob@test',
     asset_id='bitcoin#test',
     description='test',
     amount='1'
 )]
)

IrohaCrypto.sign_transaction(alice_tx, alice_key)
    net.send_tx(alice_tx)

for status in net.tx_status_stream(alice_tx):
    print(status)

iOS Swift Library

The library was created to provide convenient interface for iOS applications to communicate with Iroha blockchain including sending transactions/query, streaming transaction statuses and block commits.

Where to get

Iroha iOS library is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'IrohaCommunication'

Also you can download the source code for the library in its repo

How to use

For new Iroha users we recommend to checkout iOS example project. It tries to establish connection with Iroha peer which should be also run locally on your computer to create new account and send some asset quantity to it. To run the project, please, go through steps below:

  • Follow instructions from Iroha documentation to setup and run iroha peer in Docker container.
  • Clone iroha-ios repository.
  • cd Example directory and run pod install.
  • Open IrohaCommunication.xcworkspace in XCode
  • Build and Run IrohaExample target.
  • Consider logs to see if the scenario completed successfully.

Feel free to experiment with example project and don’t hesitate to ask any questions in Rocket.Chat.

Key Pair Format

Iroha uses key pairs (.pub and .priv keys) to sign transactions – every account has at least 1 pair. Some accounts (if quorum is more than 1) might have more Signatories that sign transactions – and each Signatory has a pair of keys. Cryptographic algorithms use those keys – and in Iroha we provide you with a choice – which algorithms to use.

Note

Check out how to create key pairs using the Python library here.

Supported Crypto Algorithms

Natively, HL Iroha uses a custom algorithm – Ed25519 with SHA-3. These keys are supported by all versions of Iroha, including the old ones. But as we all know, we need more universal options as well – that is why Iroha has HL Ursa integration – it is a library with different crypto algorithms, that allows to work with Iroha using more mainstream keys. Ursa provides Iroha with support of standard Ed25519 with SHA-2 algorithm.

Public Keys

To provide easy solution that would allow using different algorithms without “breaking” backward compatibility, we introduced multihash format for public keys in Iroha. You can learn more about multihash here.

Generally, to use keys, different from the native SHA-3 ed25519 keys, you will need to bring them to this format:

<varint key type code><varint key size in bytes><actual key bytes>

Note

In multihash, varints are the Most Significant Bit unsigned varints (also called base-128 varints).

If Iroha receives a standard public key of 32 bytes, it will treat is as a native Iroha key. If it receives a multihash public key, it will treat it based on the table below.

Right now, Iroha “understands” only one multihash key format:

Name Tag Code Description
ed25519-pub key 0xed Ed25519 public key

Examples of public keys in Iroha:

type code length data what Iroha recognises
multihash key ED01 20 62646464c35383430b… ed25519/sha2
raw 32 byte key 716fe505f69f18511a… ed25519/sha3

Note that code 0xED is encoded as ED01 by the rules of multihash format.

Private Keys

Private keys in Ursa are represented by concatenation of a private key and a public key – without multihash prefixes.

Iroha API reference

In API section we will take a look at building blocks of an application interacting with Iroha. We will overview commands and queries that the system has, and the set of client libraries encompassing transport and application layer logic.

Iroha API follows command-query separation principle.

Communication between Iroha peer and a client application is maintained via gRPC framework. Client applications should follow described protocol and form transactions accordingly to their description.

Commands

A command changes the state, called World State View, by performing an action over an entity (asset, account) in the system. Any command should be included in a transaction to perform an action.

Add asset quantity
Purpose

The purpose of add asset quantity command is to increase the quantity of an asset on account of transaction creator. Use case scenario is to increase the number of a mutable asset in the system, which can act as a claim on a commodity (e.g. money, gold, etc.)

Schema
message AddAssetQuantity {
    string asset_id = 1;
    string amount = 2;
}

Note

Please note that due to a known issue you would not get any exception if you pass invalid precision value. Valid range is: 0 <= precision <= 255

Structure
Field Description Constraint Example
Asset ID id of the asset <asset_name>#<domain_id> usd#morgan
Amount positive amount of the asset to add > 0 200.02
Validation
  1. Asset and account should exist
  2. Added quantity precision should be equal to asset precision
  3. Creator of a transaction should have a role which has permissions for issuing assets
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not add asset quantity Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to add asset quantity Grant the necessary permission
3 No such asset Cannot find asset with such name or such precision Make sure asset id and precision are correct
4 Summation overflow Resulting asset quantity is greater than the system can support Make sure that resulting quantity is less than 2^256 / 10^asset_precision
Add peer
Purpose

The purpose of add peer command is to write into ledger the fact of peer addition into the peer network. After a transaction with AddPeer has been committed, consensus and synchronization components will start using it. You can also learn more about Add Peer command.

Schema
message Peer {
  string address = 1;
  string peer_key = 2;  // hex string
  oneof certificate {
    string tls_certificate = 3;  // pem-encoded string
  }
  bool syncing_peer = 4;
}
message AddPeer {
    Peer peer = 1;
}
Structure
Field Description Constraint Example
Address resolvable address in network (IPv4, IPv6, domain name, etc.) should be resolvable 192.168.1.1:50541
Peer key peer public key, which is used in consensus algorithm to sign-off vote, commit, reject messages ed25519 public key 292a8714694095edce6be799398ed5d6244cd7be37eb813106b217d850d261f2
Validation
  1. Peer key is unique (there is no other peer with such public key)
  2. Creator of the transaction has a role which has CanAddPeer permission
  3. Such network address has not been already added
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not add peer Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to add peer Grant the necessary permission
Add signatory
Purpose

The purpose of add signatory command is to add an identifier to the account. Such identifier is a public key of another device or a public key of another user.

Schema
message AddSignatory {
    string account_id = 1;
    bytes public_key = 2;
}
Structure
Field Description Constraint Example
Account ID Account to which to add signatory <account_name>@<domain_id> makoto@soramitsu
Public key Signatory to add to account ed25519 public key 359f925e4eeecfdd6aa1abc0b79a6a121a5dd63bb612b603247ea4f8ad160156
Validation

Two cases:

Case 1. Transaction creator wants to add a signatory to his or her account, having permission CanAddSignatory

Case 2. CanAddSignatory was granted to transaction creator

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not add signatory Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to add signatory Grant the necessary permission
3 No such account Cannot find account to add signatory to Make sure account id is correct
4 Signatory already exists Account already has such signatory attached Choose another signatory
Append role
Purpose

The purpose of append role command is to promote an account to some created role in the system, where a role is a set of permissions account has to perform an action (command or query).

Schema
message AppendRole {
   string account_id = 1;
   string role_name = 2;
}
Structure
Field Description Constraint Example
Account ID id or account to append role to already existent makoto@soramitsu
Role name name of already created role already existent MoneyCreator
Validation
  1. The role should exist in the system
  2. Transaction creator should have permissions to append role (CanAppendRole)
  3. Account, which appends role, has set of permissions in his roles that is a superset of appended role (in other words no-one can append role that is more powerful than what transaction creator is)
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not append role Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to append role Grant the necessary permission
3 No such account Cannot find account to append role to Make sure account id is correct
4 No such role Cannot find role with such name Make sure role id is correct
Call engine
Purpose

The purpose of call engine command is to deploy a new contract to the Iroha EVM or to call a method of an already existing smart contract. An execution of a smart contract can potentially modify the state of the ledger provided the transaction that contains this command is accepted to a block and the block is committed.

Schema
message CallEngine {
    string caller = 1;
    oneof opt_callee {
        string callee = 2;  // hex string
    }
    string input = 3;   // hex string
}
Structure
Field Description Constraint Example
Caller Iroha account ID of an account on whose behalf the command is run <account_name>@<domain_id> test@mydomain
Callee the EVM address of a deployed smart contract 20-bytes string in hex representation 7C370993FD90AF204FD582004E2E54E6A94F2651
Input Bytecode of a smart contract for a newly deployed contracts or ABI-encoded string of the contract method selector followed by the set of its arguments Hex string 40c10f19000000000000000000000000969453762b0c739dd285b31635efa00e24c2562800000000000000000000000000000000000000000000000000000000000004d2
Validation
  1. Caller is a valid Iroha account ID
  2. The transaction creator has a role with either can_call_engine or can_call_engine_on_my_behalf permission
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Engine is not configured This error means that Iroha was built without Burrow EVM See Build section of documentation to build Iroha correctly
2 No such permissions Command’s creator does not have a permission to call EVM engine Grant the necessary permission
3 CallEngine error Code execution in EVM failed; the reason can be both in the contract code itself or be rooted in nested Iroha commands call Investigation of the error root cause is required in order to diagnose the issue
Create account
Purpose

The purpose of create account command is to make entity in the system, capable of sending transactions or queries, storing signatories, personal data and identifiers.

Schema
message CreateAccount {
    string account_name = 1;
    string domain_id = 2;
    bytes public_key = 3;
}
Structure
Field Description Constraint Example
Account name domain-unique name for account [a-z_0-9]{1,32} morgan_stanley
Domain ID target domain to make relation with should be created before the account america
Public key first public key to add to the account ed25519 public key 407e57f50ca48969b08ba948171bb2435e035d82cec417e18e4a38f5fb113f83
Validation
  1. Transaction creator has permission to create an account
  2. Domain, passed as domain_id, has already been created in the system
  3. Such public key has not been added before as first public key of account or added to a multi-signature account
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not create account Internal error happened Try again or contact developers
2 No such permissions Command’s creator either does not have permission to create account or tries to create account in a more privileged domain, than the one creator is in Grant the necessary permission or choose another domain
3 No such domain Cannot find domain with such name Make sure domain id is correct
4 Account already exists Account with such name already exists in that domain Choose another name
Create asset
Purpose

The purpose of сreate asset command is to create a new type of asset, unique in a domain. An asset is a countable representation of a commodity.

Schema
message CreateAsset {
    string asset_name = 1;
    string domain_id = 2;
    uint32 precision = 3;
}

Note

Please note that due to a known issue you would not get any exception if you pass invalid precision value. Valid range is: 0 <= precision <= 255

Structure
Field Description Constraint Example
Asset name domain-unique name for asset [a-z_0-9]{1,32} soracoin
Domain ID target domain to make relation with RFC1035 [1], RFC1123 [2] japan
Precision number of digits after comma/dot 0 <= precision <= 255 2
Validation
  1. Transaction creator has permission to create assets
  2. Asset name is unique in domain
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not create asset Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to create asset Grant the necessary permission
3 No such domain Cannot find domain with such name Make sure domain id is correct
4 Asset already exists Asset with such name already exists Choose another name
Create domain
Purpose

The purpose of create domain command is to make new domain in Iroha network, which is a group of accounts.

Schema
message CreateDomain {
    string domain_id = 1;
    string default_role = 2;
}
Structure
Field Description Constraint Example
Domain ID ID for created domain unique, RFC1035 [1], RFC1123 [2] japan05
Default role role for any created user in the domain one of the existing roles User
Validation
  1. Domain ID is unique
  2. Account, who sends this command in transaction, has role with permission to create domain
  3. Role, which will be assigned to created user by default, exists in the system
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not create domain Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to create domain Grant the necessary permission
3 Domain already exists Domain with such name already exists Choose another domain name
4 No default role found Role, which is provided as a default one for the domain, is not found Make sure the role you provided exists or create it
Create role
Purpose

The purpose of create role command is to create a new role in the system from the set of permissions. Combining different permissions into roles, maintainers of Iroha peer network can create customized security model.

Schema
message CreateRole {
    string role_name = 1;
    repeated RolePermission permissions = 2;
}
Structure
Field Description Constraint Example
Role name name of role to create [a-z_0-9]{1,32} User
RolePermission array of already existent permissions set of passed permissions is fully included into set of existing permissions {can_receive, can_transfer}
Validation
  1. Set of passed permissions is fully included into set of existing permissions
  2. Set of the permissions is not empty
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not create role Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to create role Grant the necessary permission
3 Role already exists Role with such name already exists Choose another role name
Detach role
Purpose

The purpose of detach role command is to detach a role from the set of roles of an account. By executing this command it is possible to decrease the number of possible actions in the system for the user.

Schema
message DetachRole {
    string account_id = 1;
    string role_name = 2;
}
Structure
Field Description Constraint Example
Account ID ID of account where role will be deleted already existent makoto@soramitsu
Role name a detached role name existing role User
Validation
  1. The role exists in the system
  2. The account has such role
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not detach role Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to detach role Grant the necessary permission
3 No such account Cannot find account to detach role from Make sure account id is correct
4 No such role in account’s roles Account with such id does not have role with such name Make sure account-role pair is correct
5 No such role Role with such name does not exist Make sure role id is correct
Grant permission
Purpose

The purpose of grant permission command is to give another account rights to perform actions on the account of transaction sender (give someone right to do something with my account).

Schema
message GrantPermission {
    string account_id = 1;
    GrantablePermission permission = 2;
}
Structure
Field Description Constraint Example
Account ID id of the account to which the rights are granted already existent makoto@soramitsu
GrantablePermission name name of grantable permission permission is defined CanTransferAssets
Validation
  1. Account exists
  2. Transaction creator is allowed to grant this permission
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not grant permission Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to grant permission Grant the necessary permission
3 No such account Cannot find account to grant permission to Make sure account id is correct
Remove peer
Purpose

The purpose of remove peer command is to write into ledger the fact of peer removal from the network. After a transaction with RemovePeer has been committed, consensus and synchronization components will start using it.

Schema
message RemovePeer {
    bytes public_key = 1; // hex string
}
Structure
Field Description Constraint Example
Public key peer public key, which is used in consensus algorithm to sign vote messages ed25519 public key 292a8714694095edce6be799398ed5d6244cd7be37eb813106b217d850d261f2
Validation
  1. There is more than one peer in the network
  2. Creator of the transaction has a role which has CanRemovePeer permission
  3. Peer should have been previously added to the network
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not remove peer Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to remove peer Grant the necessary permission
3 No such peer Cannot find peer with such public key Make sure that the public key is correct
4 Network size does not allow to remove peer After removing the peer the network would be empty Make sure that the network has at least two peers
Remove signatory
Purpose

Purpose of remove signatory command is to remove a public key, associated with an identity, from an account

Schema
message RemoveSignatory {
    string account_id = 1;
    bytes public_key = 2;
}
Structure
Field Description Constraint Example
Account ID id of the account to which the rights are granted already existent makoto@soramitsu
Public key Signatory to delete ed25519 public key 407e57f50ca48969b08ba948171bb2435e035d82cec417e18e4a38f5fb113f83
Validation
  1. When signatory is deleted, we should check if invariant of size(signatories) >= quorum holds
  2. Signatory should have been previously added to the account

Two cases:

Case 1. When transaction creator wants to remove signatory from their account and he or she has permission CanRemoveSignatory

Case 2. CanRemoveSignatory was granted to transaction creator

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not remove signatory Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to remove signatory from his account Grant the necessary permission
3 No such account Cannot find account to remove signatory from Make sure account id is correct
4 No such signatory Cannot find signatory with such public key Make sure public key is correct
5 Quorum does not allow to remove signatory After removing the signatory account will be left with less signatories, than its quorum allows Reduce the quorum
Revoke permission
Purpose

The purpose of revoke permission command is to revoke or dismiss given granted permission from another account in the network.

Schema
message RevokePermission {
    string account_id = 1;
    GrantablePermission permission = 2;
}
Structure
Field Description Constraint Example
Account ID id of the account to which the rights are granted already existent makoto@soramitsu
GrantablePermission name name of grantable permission permission was granted CanTransferAssets
Validation

Transaction creator should have previously granted this permission to a target account

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not revoke permission Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to revoke permission Grant the necessary permission
3 No such account Cannot find account to revoke permission from Make sure account id is correct
Set account detail
Purpose

Purpose of set account detail command is to set key-value information for a given account

Warning

If there was a value for a given key already in the storage then it will be replaced with the new value

Schema
message SetAccountDetail{
    string account_id = 1;
    string key = 2;
    string value = 3;
}
Structure
Field Description Constraint Example
Account ID id of the account to which the key-value information was set already existent makoto@soramitsu
Key key of information being set [A-Za-z0-9_]{1,64} Name
Value value of corresponding key ≤ 4096 Makoto
Validation

Three cases:

Case 1. When transaction creator wants to set account detail to other person’s account and creator has permission can_set_detail.

Case 2. can_set_my_account_detail was granted to transaction creator in order to allow them to set account details of the target account.

Case 3. When the account holder wants to set their own account details – no permission is needed in this case.

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not set account detail Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to set account detail for another account Grant the necessary permission
3 No such account Cannot find account to set account detail to Make sure account id is correct
Set account quorum
Purpose

The purpose of set account quorum command is to set the number of signatories required to confirm the identity of a user, who creates the transaction. Use case scenario is to set the number of different users, utilizing single account, to sign off the transaction.

Schema
message SetAccountQuorum {
    string account_id = 1;
    uint32 quorum = 2;
}
Structure
Field Description Constraint Example
Account ID ID of account to set quorum already existent makoto@soramitsu
Quorum number of signatories needed to be included within a transaction from this account 0 < quorum ≤ public-key set up to account ≤ 128 5
Validation

When quorum is set, it is checked if invariant of size(signatories) >= quorum holds.

Two cases:

Case 1. When transaction creator wants to set quorum for his/her account and he or she has permission CanRemoveSignatory

Case 2. CanRemoveSignatory was granted to transaction creator

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not set quorum Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to set quorum for his account Grant the necessary permission
3 No such account Cannot find account to set quorum to Make sure account id is correct
4 No signatories on account Cannot find any signatories attached to the account Add some signatories before setting quorum
5 New quorum is incorrect New quorum size is less than account’s signatories amount Choose another value or add more signatories
Subtract asset quantity
Purpose

The purpose of subtract asset quantity command is the opposite of AddAssetQuantity commands — to decrease the number of assets on account of transaction creator.

Schema
message SubtractAssetQuantity {
    string asset_id = 1;
    string amount = 2;
}

Note

Please note that due to a known issue you would not get any exception if you pass invalid precision value. Valid range is: 0 <= precision <= 255

Structure
Field Description Constraint Example
Asset ID id of the asset <asset_name>#<domain_id> usd#morgan
Amount positive amount of the asset to subtract > 0 200
Validation
  1. Asset and account should exist
  2. Added quantity precision should be equal to asset precision
  3. Creator of the transaction should have a role which has permissions for subtraction of assets
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not subtract asset quantity Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to subtract asset quantity Grant the necessary permission
3 No such asset found Cannot find asset with such name or precision in account’s assets Make sure asset name and precision are correct
4 Not enough balance Account’s balance is too low to perform the operation Add asset to account or choose lower value to subtract
Transfer asset
Purpose

The purpose of transfer asset command is to share assets within the account in peer network: in the way that source account transfers assets to the target account.

Schema
message TransferAsset {
    string src_account_id = 1;
    string dest_account_id = 2;
    string asset_id = 3;
    string description = 4;
    string amount = 5;
}
Structure
Field Description Constraint Example
Source account ID ID of the account to withdraw the asset from already existent makoto@soramitsu
Destination account ID ID of the account to send the asset to already existent alex@california
Asset ID ID of the asset to transfer already existent usd#usa
Description Message to attach to the transfer Max length of description (set in genesis block, by default is 100*1024) here’s my money take it
Amount amount of the asset to transfer 0 <= precision <= 255 200.20
Validation
  1. Source account has this asset in its AccountHasAsset relation [1]
  2. An amount is a positive number and asset precision is consistent with the asset definition
  3. Source account has enough amount of asset to transfer and is not zero
  4. Source account can transfer money, and destination account can receive money (their roles have these permissions)
  5. Description length is less than 100*1024 (one hundred kilobytes) and less than ‘MaxDescriptionSize’ setting value if set.
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not transfer asset Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to transfer asset from his account Grant the necessary permission
3 No such source account Cannot find account with such id to transfer money from Make sure source account id is correct
4 No such destination account Cannot find account with such id to transfer money to Make sure destination account id is correct
5 No such asset found Cannot find such asset Make sure asset name and precision are correct
6 Not enough balance Source account’s balance is too low to perform the operation Add asset to account or choose lower value to subtract
7 Too much asset to transfer Resulting asset quantity of destination account would exceed the allowed maximum Make sure that the final destination value is less than 2^256 / 10^asset_precision
8 Too long description Too long description Ensure that description length matches the criteria above (or just shorten it)
[1](1, 2, 3) https://www.ietf.org/rfc/rfc1035.txt
[2](1, 2) https://www.ietf.org/rfc/rfc1123.txt
Compare and Set Account Detail
Purpose

Purpose of compare and set account detail command is to set key-value information for a given account if the old value matches the value passed.

Schema
message CompareAndSetAccountDetail{
    string account_id = 1;
    string key = 2;
    string value = 3;
    oneof opt_old_value {
        string old_value = 4;
    }
    bool check_empty = 5;
}

Note

Pay attention, that old_value field is optional. This is due to the fact that the key-value pair might not exist.

Structure
Field Description Constraint Example
Account ID id of the account to which the key-value information was set. If key-value pair doesnot exist , then it will be created an existing account artyom@soramitsu
Key key of information being set [A-Za-z0-9_]{1,64} Name
Value new value for the corresponding key length of value ≤ 4096 Artyom
Old value current value for the corresponding key length of value ≤ 4096 Artem
check_empty if true, empty old_value in command must match absent value in WSV; if false, any old_value in command matches absent in WSV (legacy) bool true
Validation

Three cases:

Case 1. When transaction creator wants to set account detail to his/her account and he or she has permission GetMyAccountDetail / GetAllAccountsDetail / GetDomainAccountDetail

Case 2. When transaction creator wants to set account detail to another account and he or she has permissions SetAccountDetail and GetAllAccountsDetail / GetDomainAccountDetail

Case 3. SetAccountDetail permission was granted to transaction creator and he or she has permission GetAllAccountsDetail / GetDomainAccountDetail

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not compare and set account detail Internal error happened Try again or contact developers
2 No such permissions Command’s creator does not have permission to set and read account detail for this account Grant the necessary permission
3 No such account Cannot find account to set account detail to Make sure account id is correct
4 No match values Old values do not match Make sure old value is correct
Set setting value
Purpose

The purpose of set setting value command is to enable customization to your needs.

Schema
message SetSettingValue {
    string key = 1;
    string value = 2;
}
Structure
Field Description Constraint Example
Key Key of the setting list of possible settings MaxDescriptionSize
Value Value of the setting type of setting 255
Validation
  1. Command can be executed only from genesis block
List of possible settings
Key Value constraint Description
MaxDescriptionSize Unsigned integer, 0 <= MaxDescriptionSize < 2^32 Maximum transaction description length

Queries

A query is a request related to certain part of World State View — the latest state of blockchain. Query cannot modify the contents of the chain and a response is returned to any client immediately after receiving peer has processed a query.

Validation

The validation for all queries includes:

  • timestamp — shouldn’t be from the past (24 hours prior to the peer time) or from the future (range of 5 minutes added to the peer time)
  • signature of query creator — used for checking the identity of query creator
  • query counter — checked to be incremented with every subsequent query from query creator
  • roles — depending on the query creator’s role: the range of state available to query can relate to to the same account, account in the domain, to the whole chain, or not allowed at all
Result Pagination

Some queries support TxPaginationMeta that allows to customise and sort the query result in different ways what could be used in development. Pagination works together with ordering prameters, similar to ORDER BY in SQL language – “the result rows are sorted according to the specified expression (in Iroha – Field). If two rows are equal according to the leftmost expression, they are compared according to the next expression and so on.”

Here is how the “expression” is specified:

enum Field {
    kCreatedTime = 0;
    kPosition = 1;
}

There are 2 bases for ordering – on creation time and depending on the number of block.

There is an ascending and descending directions for each Field:

enum Direction {
    kAscending = 0;
    kDescending = 1;
}

Now, the ordering itself:

message Ordering {
    message FieldOrdering {
      Field field = 1;
      Direction direction = 2;
    }
    repeated FieldOrdering sequence = 1;
}

After ordering is specified, pagination can be executed:

message TxPaginationMeta {
  uint32 page_size = 1;
  oneof opt_first_tx_hash {
    string first_tx_hash = 2;
  }
  Ordering ordering = 3;
  oneof opt_first_tx_time {
    google.protobuf.Timestamp first_tx_time = 4;
  }
  oneof opt_last_tx_time {
    google.protobuf.Timestamp last_tx_time = 5;
  }
  oneof opt_first_tx_height {
    uint64 first_tx_height = 6;
  }
  oneof opt_last_tx_height {
    uint64 last_tx_height = 7;
  }
}
What is added to the request structure in case of pagination
Field Description Constraint Example
Page size size of the page to be returned by the query, if the response contains fewer transactions than a page size, then next tx hash will be empty in response page_size > 0 5
First tx hash hash of the first transaction in the page. If that field is not set — then the first transactions are returned hash in hex format bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308929
ordering how the results should be ordered (before pagination is applied) see fields below see fields below
ordering.sequence ordeing spec, like in SQL ORDER BY sequence of fields and directions [{kCreatedTime, kAscending}, {kPosition, kDescending}]
First tx time time of the first transaction in query result. If that field is not set - then the transactions starting from first are returned Google Protocol Buffer Timestamp type 0001-01-01T00:00:00Z <= first tx time <= 9999-12-31T23:59:59.999999999Z
Last tx time time of the last transaction in query result. If that field is not set - then the transactions up to the last are returned Google Protocol Buffer Timestamp type 0001-01-01T00:00:00Z <= last tx time <= 9999-12-31T23:59:59.999999999Z
First tx height block height of the first transaction in query result. If that field is not set - then the transactions starting from height 1 are returned first tx height > 0 4
Last tx height block height of the last transaction in query result. If that field is not set - then the transactions up to the last one are returned last tx height > 0 6
Engine Receipts
Purpose

Retrieve a receipt of a CallEngine command. Similar to the eth.GetTransactionReceipt API call of Ethereum JSON RPC API. Allows to access the event log created during computations inside the EVM.

Request Schema
message GetEngineReceipts {
    string tx_hash = 1;     // hex string
}
Request Structure
Field Description Constraint Example
Transaction Hash hash of the transaction that has the CallEngine command hash in hex format 5241f70cf3adbc180199c1d2d02db82334137aede5f5ed35d649bbbc75ab2634
Response Schema
message EngineReceiptsResponse {
    repeated EngineReceipt engine_receipt = 1;
}
message EngineReceipt {
    int32 command_index = 1;
    string caller = 2;
    oneof opt_to_contract_address {
        CallResult call_result = 3;
        string contract_address = 4;
    }
    repeated EngineLog logs = 5;
}
message CallResult {
    string callee = 1;
    string result_data = 2;
}
message EngineLog {
    string address = 1;         // hex string
    string data = 2;            // hex string
    repeated string topics = 3; // hex string
}
Response Structure
Field Description Constraint Example
command_index Index of the CallEngine command in the transaction non-negative integer 0
caller caller account of the smart contract <account_name>@<domain_id> admin@test
call_result.callee address of called contract 20-bytes string in hex representation 0000000000000000000000000000000000000000
call_result.result_data the value returned by the contract string in hex representation 00
contract_address EVM address of a newly deployed contract 20-bytes string in hex representation 7C370993FD90AF204FD582004E2E54E6A94F2651
logs Array of EVM event logs created during smart contract execution. see below see below
logs.[].address the contract caller EVM address 20-bytes string in hex representation 577266A3CE7DD267A4C14039416B725786605FF4
logs.[].data the logged data hex string 0000000000000000000000007203DF5D7B4F198848477D7F9EE080B207E544DD000000000000000000000000000000000000000000000000000000000000006D
logs.[].topics log topic as in Ethereum 32-byte strings [3990DB2D31862302A685E8086B5755072A6E2B5B780AF1EE81ECE35EE3CD3345, 000000000000000000000000969453762B0C739DD285B31635EFA00E24C25628]
Possible Stateful Validation Errors
Code Error Name Description How to solve
2 No such permissions Query’s creator does not have any of the permissions to get the call engine receipt Grant the necessary permission
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
Get Account
Purpose

Purpose of get account query is to get the state of an account.

Request Schema
message GetAccount {
    string account_id = 1;
}
Request Structure
Field Description Constraint Example
Account ID account id to request its state <account_name>@<domain_id> alex@morgan
Response Schema
message AccountResponse {
    Account account = 1;
    repeated string account_roles = 2;
}

message Account {
    string account_id = 1;
    string domain_id = 2;
    uint32 quorum = 3;
    string json_data = 4;
}
Response Structure
Field Description Constraint Example
Account ID account id <account_name>@<domain_id> alex@morgan
Domain ID domain where the account was created RFC1035 [1], RFC1123 [2] morgan
Quorum number of signatories needed to sign the transaction to make it valid 0 < quorum ≤ 128 5
JSON data key-value account information JSON { genesis: {name: alex} }
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get account Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get account Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
Get Block
Purpose

Purpose of get block query is to get a specific block, using its height as an identifier

Request Schema
message GetBlock {
    uint64 height = 1;
}
Request Structure
Field Description Constraint Example
Height height of the block to be retrieved 0 < height < 2^64 42
Response Schema
message BlockResponse {
    Block block = 1;
}
Response Structure
Field Description Constraint Example
Block the retrieved block block structure block
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get block Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have a permission to get block Grant can_get_block permission
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
3 Invalid height Supplied height is not uint_64 or greater than the ledger’s height Check the height and try again

Note

Error code 3 is ambiguous for this query. It indicates either invalid signatories or invalid height. Use this method with height = 1 (first block is always present) to check for invalid signatories.

Get Signatories
Purpose

Purpose of get signatories query is to get signatories, which act as an identity of the account.

Request Schema
message GetSignatories {
    string account_id = 1;
}
Request Structure
Field Description Constraint Example
Account ID account id to request signatories <account_name>@<domain_id> alex@morgan
Response Schema
message SignatoriesResponse {
    repeated bytes keys = 1;
}
Response Structure
Field Description Constraint Example
Keys an array of public keys ed25519 292a8714694095edce6be799398ed5d6244cd7be37eb813106b217d850d261f2
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get signatories Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get signatories Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
Get Transactions
Purpose

GetTransactions is used for retrieving information about transactions, based on their hashes.

Note

This query is valid if and only if all the requested hashes are correct: corresponding transactions exist, and the user has a permission to retrieve them

Request Schema
message GetTransactions {
    repeated bytes tx_hashes = 1;
}
Request Structure
Field Description Constraint Example
Transactions hashes an array of hashes array with 32 byte hashes {hash1, hash2…}
Response Schema
message TransactionsResponse {
    repeated Transaction transactions = 1;
}
Response Structure
Field Description Constraint Example
Transactions an array of transactions Committed transactions {tx1, tx2…}
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get transactions Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get transactions Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
4 Invalid hash At least one of the supplied hashes either does not exist in user’s transaction list or creator of the query does not have permissions to see it Check the supplied hashes and try again
Get Pending Transactions
Purpose

GetPendingTransactions is used for retrieving a list of pending (not fully signed) multisignature transactions or batches of transactions issued by account of query creator.

Note

This query uses pagination for quicker and more convenient query responses. Please read about it and specify pagination before sending the query request as well as the request structure.

Request Schema
message GetPendingTransactions {
    TxPaginationMeta pagination_meta = 1;
}

All the user’s semi-signed multisignature (pending) transactions can be queried. Maximum amount of transactions contained in a response can be limited by page_size field. All the pending transactions are stored till they have collected enough signatures or get expired. The mutual order of pending transactions or batches of transactions is preserved for a user. That allows a user to query all transactions sequentially - page by page. Each response may contain a reference to the next batch or transaction that can be queried. A page size can be greater than the size of the following batch (in transactions). In that case, several batches or transactions will be returned. During navigating over pages, the following batch can collect the missing signatures before it gets queried. This will result in stateful failed query response due to a missing hash of the batch.

Example

If there are two pending batches with three transactions each and a user queries pending transactions with page size 5, then the transactions of the first batch will be in the response and a reference (first transaction hash and batch size, even if it is a single transaction in fact) to the second batch will be specified too. Transactions of the second batch are not included in the first response because the batch cannot be devided into several parts and only complete batches can be contained in a response.

Response Schema
message PendingTransactionsPageResponse {
    message BatchInfo {
        string first_tx_hash = 1;
        uint32 batch_size = 2;
    }
    repeated Transaction transactions = 1;
    uint32 all_transactions_size = 2;
    BatchInfo next_batch_info = 3;
}
Response Structure

The response contains a list of pending transactions, the amount of all stored pending transactions for the user and the information required to query the subsequent page (if exists).

Field Description Constraint Example
Transactions an array of pending transactions Pending transactions {tx1, tx2…}
All transactions size the number of stored transactions all_transactions_size >= 0 0
Next batch info A reference to the next page - the message might be not set in a response    
First tx hash hash of the first transaction in the next batch hash in hex format bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308929
Batch size Minimum page size required to fetch the next batch batch_size > 0 3
Get Pending Transactions (deprecated)

Warning

The query without parameters is deprecated now and will be removed in the following major Iroha release (2.0). Please use the new query version instead: Get Pending Transactions.

Purpose

GetPendingTransactions is used for retrieving a list of pending (not fully signed) multisignature transactions or batches of transactions issued by account of query creator.

Request Schema
message GetPendingTransactions {
}
Response Schema
message TransactionsResponse {
    repeated Transaction transactions = 1;
}
Response Structure

The response contains a list of pending transactions.

Field Description Constraint Example
Transactions an array of pending transactions Pending transactions {tx1, tx2…}
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get pending transactions Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get pending transactions Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
Get Account Transactions
Purpose

In a case when a list of transactions per account is needed, GetAccountTransactions query can be formed.

Note

This query uses pagination for quicker and more convenient query responses. Please read about it and specify pagination before sending the query request as well as the request structure.

Request Schema
message GetAccountTransactions {
    string account_id = 1;
    TxPaginationMeta pagination_meta = 2;
}
Request Structure
Field Description Constraint Example
Account ID account id to request transactions from <account_name>@<domain_id> makoto@soramitsu
Response Schema
message TransactionsPageResponse {
    repeated Transaction transactions = 1;
    uint32 all_transactions_size = 2;
    oneof next_page_tag {
        string next_tx_hash = 3;
    }
}
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get account transactions Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get account transactions Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
4 Invalid pagination hash Supplied hash does not appear in any of the user’s transactions Make sure hash is correct and try again
5 Invalid account id User with such account id does not exist Make sure account id is correct
Response Structure
Field Description Constraint Example
Transactions an array of transactions for given account Committed transactions {tx1, tx2…}
All transactions size total number of transactions created by the given account   100
Next transaction hash hash pointing to the next transaction after the last transaction in the page. Empty if a page contains the last transaction for the given account bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308929  
Get Account Asset Transactions
Purpose

GetAccountAssetTransactions query returns all transactions associated with given account and asset.

Note

This query uses pagination for quicker and more convenient query responses. Please read about it and specify pagination before sending the query request as well as the request structure.

Request Schema
message GetAccountAssetTransactions {
    string account_id = 1;
    string asset_id = 2;
    TxPaginationMeta pagination_meta = 3;
}
Request Structure
Field Description Constraint Example
Account ID account id to request transactions from <account_name>@<domain_id> makoto@soramitsu
Asset ID asset id in order to filter transactions containing this asset <asset_name>#<domain_id> jpy#japan
Response Schema
message TransactionsPageResponse {
    repeated Transaction transactions = 1;
    uint32 all_transactions_size = 2;
    oneof next_page_tag {
        string next_tx_hash = 3;
    }
}
Response Structure
Field Description Constraint Example
Transactions an array of transactions for given account and asset Committed transactions {tx1, tx2…}
All transactions size total number of transactions for given account and asset   100
Next transaction hash hash pointing to the next transaction after the last transaction in the page. Empty if a page contains the last transaction for given account and asset bddd58404d1315e0eb27902c5d7c8eb0602c16238f005773df406bc191308929  
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get account asset transactions Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get account asset transactions Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
4 Invalid pagination hash Supplied hash does not appear in any of the user’s transactions Make sure hash is correct and try again
5 Invalid account id User with such account id does not exist Make sure account id is correct
6 Invalid asset id Asset with such asset id does not exist Make sure asset id is correct
Get Account Assets
Purpose

To get the state of all assets in an account (a balance), GetAccountAssets query can be used.

Request Schema
message AssetPaginationMeta {
    uint32 page_size = 1;
    oneof opt_first_asset_id {
        string first_asset_id = 2;
    }
}

message GetAccountAssets {
    string account_id = 1;
    AssetPaginationMeta pagination_meta = 2;
}
Request Structure
Field Description Constraint Example
Account ID account id to request balance from <account_name>@<domain_id> makoto@soramitsu
AssetPaginationMeta.page_size Requested page size. The number of assets in response will not exceed this value. If the response was truncated, the asset id immediately following the returned ones will be provided in next_asset_id. 0 < page_size < 32 bit unsigned int max (4294967296) 100
AssetPaginationMeta.first_asset_id Requested page start. If the field is not set, then the first page is returned. name#domain my_asset#my_domain
Response Schema
message AccountAssetResponse {
    repeated AccountAsset account_assets = 1;
    uint32 total_number = 2;
    oneof opt_next_asset_id {
        string next_asset_id = 3;
    }
}

message AccountAsset {
    string asset_id = 1;
    string account_id = 2;
    string balance = 3;
}
Response Structure
Field Description Constraint Example
Asset ID identifier of asset used for checking the balance <asset_name>#<domain_id> jpy#japan
Account ID account which has this balance <account_name>@<domain_id> makoto@soramitsu
Balance balance of the asset No less than 0 200.20
total_number number of assets matching query without page limits 0 < total_number < 32 bit unsigned int max (4294967296) 100500
next_asset_id the id of asset immediately following curent page name#domain my_asset#my_domain

Note

If page size is equal or greater than the number of assets matching other requested criteria, the next asset id will be unset in the response. Otherwise, it contains the value that clients should use for the first asset id if they want to fetch the next page.

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get account assets Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get account assets Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
4 Invalid pagination metadata Wrong page size or nonexistent first asset Set a valid page size, and make sure that asset id is valid, or leave first asset id unspecified
Get Account Detail
Purpose

To get details of the account, GetAccountDetail query can be used. Account details are key-value pairs, splitted into writers categories. Writers are accounts, that added the corresponding account detail. Example of such structure is:

{
    "account@a_domain": {
        "age": 18,
        "hobbies": "crypto"
    },
    "account@b_domain": {
        "age": 20,
        "sports": "basketball"
    }
}

Here, one can see four account details - “age”, “hobbies” and “sports” - added by two writers - “account@a_domain” and “account@b_domain”. All of these details, obviously, are about the same account.

Request Schema
message AccountDetailRecordId {
    string writer = 1;
    string key = 2;
}

message AccountDetailPaginationMeta {
    uint32 page_size = 1;
    AccountDetailRecordId first_record_id = 2;
}

message GetAccountDetail {
    oneof opt_account_id {
      string account_id = 1;
    }
    oneof opt_key {
      string key = 2;
    }
    oneof opt_writer {
      string writer = 3;
    }
    AccountDetailPaginationMeta pagination_meta = 4;
}

Note

Pay attention, that all fields except pagination meta are optional. The reasons for that are described below.

Warning

Pagination metadata can be missing in the request for compatibility reasons, but this behaviour is deprecated and should be avoided.

Request Structure
Field Description Constraint Example
Account ID account id to get details from <account_name>@<domain_id> account@domain
Key key, under which to get details string age
Writer account id of writer <account_name>@<domain_id> account@domain
AccountDetailPaginationMeta.page_size Requested page size. The number of records in response will not exceed this value. If the response was truncated, the record id immediately following the returned ones will be provided in next_record_id. 0 < page_size < 32 bit unsigned int max (4294967296) 100
AccountDetailPaginationMeta.first_record_id.writer requested page start by writer name#domain my_asset#my_domain
AccountDetailPaginationMeta.first_record_id.key requested page start by key string age

Note

When specifying first record id, it is enough to provide the attributes (writer, key) that are unset in the main query.

Response Schema
message AccountDetailResponse {
    string detail = 1;
    uint64 total_number = 2;
    AccountDetailRecordId next_record_id = 3;
}
Response Structure
Field Description Constraint Example
Detail key-value pairs with account details JSON see below
total_number number of records matching query without page limits 0 < total_number < 32 bit unsigned int max (4294967296) 100
next_record_id.writer the writer account of the record immediately following curent page <account_name>@<domain_id> pushkin@lyceum.tsar
next_record_id.key the key of the record immediately following curent page string cold and sun
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get account detail Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get account detail Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
4 Invalid pagination metadata Wrong page size or nonexistent first record Set valid page size, and make sure that the first record id is valid, or leave the first record id unspecified
Usage Examples

Again, let’s consider the example of details from the beginning and see how different variants of GetAccountDetail queries will change the resulting response.

{
    "account@a_domain": {
        "age": 18,
        "hobbies": "crypto"
    },
    "account@b_domain": {
        "age": 20,
        "sports": "basketball"
    }
}

account_id is not set

If account_id is not set - other fields can be empty or not - it will automatically be substituted with query creator’s account, which will lead to one of the next cases.

only account_id is set

In this case, all details about that account are going to be returned, leading to the following response:

{
    "account@a_domain": {
        "age": 18,
        "hobbies": "crypto"
    },
    "account@b_domain": {
        "age": 20,
        "sports": "basketball"
    }
}

account_id and key are set

Here, details added by all writers under the key are going to be returned. For example, if we asked for the key “age”, that’s the response we would get:

{
    "account@a_domain": {
        "age": 18
    },
    "account@b_domain": {
        "age": 20
    }
}

account_id and writer are set

Now, the response will contain all details about this account, added by one specific writer. For example, if we asked for writer “account@b_domain”, we would get:

{
    "account@b_domain": {
        "age": 20,
        "sports": "basketball"
    }
}

account_id, key and writer are set

Finally, if all three field are set, result will contain details, added the specific writer and under the specific key, for example, if we asked for key “age” and writer “account@a_domain”, we would get:

{
    "account@a_domain": {
        "age": 18
    }
}
Get Asset Info
Purpose

In order to get information on the given asset (as for now - its precision), user can send GetAssetInfo query.

Request Schema
message GetAssetInfo {
    string asset_id = 1;
}
Request Structure
Field Description Constraint Example
Asset ID asset id to know related information <asset_name>#<domain_id> jpy#japan
Response Schema
message Asset {
    string asset_id = 1;
    string domain_id = 2;
    uint32 precision = 3;
}

Note

Please note that due to a known issue you would not get any exception if you pass invalid precision value. Valid range is: 0 <= precision <= 255

Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get asset info Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get asset info Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
Response Structure
Field Description Constraint Example
Asset ID identifier of asset used for checking the balance <asset_name>#<domain_id> jpy#japan
Domain ID domain related to this asset RFC1035 [1], RFC1123 [2] japan
Precision number of digits after comma 0 <= precision <= 255 2
Get Roles
Purpose

To get existing roles in the system, a user can send GetRoles query to Iroha network.

Request Schema
message GetRoles {
}
Response Schema
message RolesResponse {
    repeated string roles = 1;
}
Response Structure
Field Description Constraint Example
Roles array of created roles in the network set of roles in the system {MoneyCreator, User, Admin, …}
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get roles Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get roles Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
Get Role Permissions
Purpose

To get available permissions per role in the system, a user can send GetRolePermissions query to Iroha network.

Request Schema
message GetRolePermissions {
    string role_id = 1;
}
Request Structure
Field Description Constraint Example
Role ID role to get permissions for existing role in the system MoneyCreator
Response Schema
message RolePermissionsResponse {
    repeated string permissions = 1;
}
Response Structure
Field Description Constraint Example
Permissions array of permissions related to the role string of permissions related to the role {can_add_asset_qty, …}
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get role permissions Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get role permissions Grant the necessary permission: individual, global or domain one
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories
[1](1, 2) https://www.ietf.org/rfc/rfc1035.txt
[2](1, 2) https://www.ietf.org/rfc/rfc1123.txt
Get Peers
Purpose

A query that returns a list of peers in Iroha network.

Request Schema
message GetPeers {
}
Response Schema
message Peer {
    string address = 1;
    string peer_key = 2; // hex string
}

message PeersResponse {
    repeated Peer peers = 1;
}
Response Structure

A list of peers with their addresses and public keys is returned.

Field Description Constraint Example
Peers array of peers from the network non-empty list of peers {Peer{“peer.domain.com”, “292a8714694095edce6be799398ed5d6244cd7be37eb813106b217d850d261f2”}, …}
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get peers Internal error happened Try again or contact developers
2 No such permissions Query creator does not have enough permissions to get peers Append a role with can_get_blocks or can_get_peers permission
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories

Warning

Currently Get Peers query uses “can_get_blocks” permission for compatibility purposes. Later that will be changed to “can_get_peers” with the next major Iroha release.

Fetch Commits
Purpose

To get new blocks as soon as they are committed, a user can invoke FetchCommits RPC call to Iroha network.

Request Schema

No request arguments are needed

Response Schema
message BlockQueryResponse {
    oneof response {
        BlockResponse block_response = 1;
        BlockErrorResponse block_error_response = 2;
    }
}

message BlockResponse {
    Block block = 1;
}

message BlockErrorResponse {
    string message = 1;
}

Please note that it returns a stream of BlockQueryResponse.

Response Structure
Field Description Constraint Example
Block Iroha block only committed blocks { ‘block_v1’: ….}
Possible Stateful Validation Errors
Code Error Name Description How to solve
1 Could not get block streaming Internal error happened Try again or contact developers
2 No such permissions Query’s creator does not have any of the permissions to get blocks Grant can_get_block permission
3 Invalid signatures Signatures of this query did not pass validation Add more signatures and make sure query’s signatures are a subset of account’s signatories

Note

BlockErrorResponse contains only message field. In case of stateful validation error it will be “stateful invalid”. GetBlock requires same can_get_block permission. Therefore, it can be used with height = 1 (first block is always present) to check for invalid signatories or insufficient permissions.

Example

You can check an example how to use this query here: https://github.com/x3medima17/twitter

Permissions

Hyperledger Iroha uses a role-based access control system to limit actions of its users. This system greatly helps to implement use cases involving user groups having different access levels — ranging from the weak users, who can’t even receive asset transfer to the super-users. The beauty of our permission system is that you don’t have to have a super-user in your Iroha setup or use all the possible permissions: you can create segregated and lightweight roles.

Maintenance of the system involves setting up roles and permissions, that are included in the roles. This might be done at the initial step of system deployment — in genesis block, or later when Iroha network is up and running, roles can be changed (if there is a role that can do that :)

This section will help you to understand permissions and give you an idea of how to create roles including certain permissions. Each permission is provided with an example written in Python that demonstrates the way of transaction or query creation, which require specific permission. Every example uses commons.py module, which listing is available at Supplementary Sources section.

List of Permissions

Permission Name Category Type
root All Categories Command and Query
can_create_account Account Command
can_set_detail Account Command
can_set_my_account_detail grantable Account Command
can_create_asset Asset Command
can_receive Asset Command
can_transfer Asset Command
can_transfer_my_assets grantable Asset Command
can_add_asset_qty Asset Quantity Command
can_subtract_asset_qty Asset Quantity Command
can_add_domain_asset_qty Asset Quantity Command
can_subtract_domain_asset_qty Asset Quantity Command
can_create_domain Domain Command
can_grant_can_add_my_signatory Grant Command
can_grant_can_remove_my_signatory Grant Command
can_grant_can_set_my_account_detail Grant Command
can_grant_can_set_my_quorum Grant Command
can_grant_can_transfer_my_assets Grant Command
can_add_peer Peer Command
can_remove_peer Peer Command
can_append_role Role Command
can_create_role Role Command
can_detach_role Role Command
can_add_my_signatory grantable Signatory Command
can_add_signatory Signatory Command
can_remove_my_signatory grantable Signatory Command
can_remove_signatory Signatory Command
can_set_my_quorum grantable Signatory Command
can_set_quorum Signatory Command
can_call_engine Engine Command
can_call_engine_on_my_behalf grantable Engine Command
can_grant_can_call_engine_on_my_behalf Grant Command
can_get_all_acc_detail Account Query
can_get_all_accounts Account Query
can_get_domain_acc_detail Account Query
can_get_domain_accounts Account Query
can_get_my_acc_detail Account Query
can_get_my_account Account Query
can_get_all_acc_ast Account Asset Query
can_get_domain_acc_ast Account Asset Query
can_get_my_acc_ast Account Asset Query
can_get_all_acc_ast_txs Account Asset Transaction Query
can_get_domain_acc_ast_txs Account Asset Transaction Query
can_get_my_acc_ast_txs Account Asset Transaction Query
can_get_all_acc_txs Account Transaction Query
can_get_domain_acc_txs Account Transaction Query
can_get_my_acc_txs Account Transaction Query
can_read_assets Asset Query
can_get_blocks Block Stream Query
can_get_roles Role Query
can_get_all_signatories Signatory Query
can_get_domain_signatories Signatory Query
can_get_my_signatories Signatory Query
can_get_all_txs Transaction Query
can_get_my_txs Transaction Query
can_get_peers Peer Query
can_get_my_engine_receipts Engine receipts Query
can_get_domain_engine_receipts Engine receipts Query
can_get_all_engine_receipts Engine receipts Query

Permissions Detailed

Supplementary Sources
commons.py
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#
# Copyright Soramitsu Co., Ltd. All Rights Reserved.
# SPDX-License-Identifier: Apache-2.0
#

from iroha import primitive_pb2
from iroha import Iroha, IrohaCrypto
import binascii
from time import time

command = Iroha.command


def now():
    return int(time() * 1000)


def all_permissions():
    return [
        primitive_pb2.can_append_role,
        primitive_pb2.can_create_role,
        primitive_pb2.can_detach_role,
        primitive_pb2.can_add_asset_qty,
        primitive_pb2.can_subtract_asset_qty,
        primitive_pb2.can_add_peer,
        primitive_pb2.can_add_signatory,
        primitive_pb2.can_remove_signatory,
        primitive_pb2.can_set_quorum,
        primitive_pb2.can_create_account,
        primitive_pb2.can_set_detail,
        primitive_pb2.can_create_asset,
        primitive_pb2.can_transfer,
        primitive_pb2.can_receive,
        primitive_pb2.can_create_domain,
        primitive_pb2.can_read_assets,
        primitive_pb2.can_get_roles,
        primitive_pb2.can_get_my_account,
        primitive_pb2.can_get_all_accounts,
        primitive_pb2.can_get_domain_accounts,
        primitive_pb2.can_get_my_signatories,
        primitive_pb2.can_get_all_signatories,
        primitive_pb2.can_get_domain_signatories,
        primitive_pb2.can_get_my_acc_ast,
        primitive_pb2.can_get_all_acc_ast,
        primitive_pb2.can_get_domain_acc_ast,
        primitive_pb2.can_get_my_acc_detail,
        primitive_pb2.can_get_all_acc_detail,
        primitive_pb2.can_get_domain_acc_detail,
        primitive_pb2.can_get_my_acc_txs,
        primitive_pb2.can_get_all_acc_txs,
        primitive_pb2.can_get_domain_acc_txs,
        primitive_pb2.can_get_my_acc_ast_txs,
        primitive_pb2.can_get_all_acc_ast_txs,
        primitive_pb2.can_get_domain_acc_ast_txs,
        primitive_pb2.can_get_my_txs,
        primitive_pb2.can_get_all_txs,
        primitive_pb2.can_get_blocks,
        primitive_pb2.can_grant_can_set_my_quorum,
        primitive_pb2.can_grant_can_add_my_signatory,
        primitive_pb2.can_grant_can_remove_my_signatory,
        primitive_pb2.can_grant_can_transfer_my_assets,
        primitive_pb2.can_grant_can_set_my_account_detail
    ]


def genesis_block(admin, alice, test_permissions, multidomain=False):
    """
    Compose a set of common for all tests' genesis block transactions
    :param admin: dict of id and private key of admin
    :param alice: dict of id and private key of alice
    :param test_permissions: permissions for users in test domain
    :param multidomain: admin and alice accounts will be created in
    different domains and the first domain users will have admin right
    by default if True
    :return: a list of Iroha.command's
    """
    peer = primitive_pb2.Peer()
    peer.address = '127.0.0.1:50541'
    peer.peer_key = IrohaCrypto.derive_public_key(admin['key'])
    commands = [
        command('AddPeer', peer=peer),
        command('CreateRole', role_name='admin_role', permissions=all_permissions()),
        command('CreateRole', role_name='test_role', permissions=test_permissions)]
    if multidomain:
        commands.append(command('CreateDomain', domain_id='first', default_role='admin_role'))
    commands.extend([
        command('CreateDomain',
                domain_id='second' if multidomain else 'test',
                default_role='test_role'),
        command('CreateAccount',
                account_name='admin',
                domain_id='first' if multidomain else 'test',
                public_key=IrohaCrypto.derive_public_key(admin['key'])),
        command('CreateAccount',
                account_name='alice',
                domain_id='second' if multidomain else 'test',
                public_key=IrohaCrypto.derive_public_key(alice['key']))
    ])
    if not multidomain:
        commands.append(command('AppendRole', account_id=admin['id'], role_name='admin_role'))
    return commands


def new_user(user_id):
    private_key = IrohaCrypto.private_key()
    if user_id.lower().startswith('admin'):
        print('K{}'.format(private_key.decode('utf-8')))
    return {
        'id': user_id,
        'key': private_key
    }


def hex(generator):
    """
    Decorator for transactions' and queries generators.

    Allows preserving the type of binaries for Binary Testing Framework.
    """
    prefix = 'T' if generator.__name__.lower().endswith('tx') else 'Q'
    print('{}{}'.format(prefix, binascii.hexlify(generator().SerializeToString()).decode('utf-8')))

Commands here are parts of transaction - a state-changing set of actions in the system. When a transaction passes validation and consensus stages, it is written in a block and saved in immutable block store (blockchain).

Transactions consist of commands, performing an action over an entity in the system. The entity might be an account, asset, etc.

Use Case Scenarios

We list a number of use cases and specific advantages that Hyperledger Iroha can introduce to these applications. We hope that the applications and use cases will inspire developers and creators to further innovation with Hyperledger Iroha.

Certificates in Education, Healthcare

Hyperledger Iroha incorporates into the system multiple certifying authorities such as universities, schools, and medical institutions. Flexible permission model used in Hyperledger Iroha allows building certifying identities, and grant certificates. The storage of explicit and implicit information in users’ account allows building various reputation and identity systems.

By using Hyperledger Iroha each education or medical certificate can be verified that it was issued by certain certifying authorities. Immutability and clear validation rules provide transparency to health and education significantly reducing the usage of fake certificates.

Example

Imagine a medical institution registered as a hospital domain in Hyperledger Iroha. This domain has certified and registered workers each having some role, e.g. physician, therapist, nurse. Each patient of the hospital has an account with full medical history. Each medical record, like blood test results, is securely and privately stored in the account of the patient as JSON key/values. Rules in hospital domain are defined such that only certified medical workers and the user can access the personal information. The medical data returned by a query is verified that it comes from a trusted source.

Hospital is tied to a specific location, following legal rules of that location, like storing personal data of citizens only in specific regions(privacy rules). A multi-domain approach in Hyperledger Iroha allows sharing information across multiple countries not violating legal rules. For example, if the user makoto@hospital decides to share personal case history with a medical institution in another country, the user can use grant command with permission can_get_my_acc_detail.

Similar to a medical institution, a registered university in Hyperledger Iroha has permissions to push information to the graduated students. A diploma or certificate is essentially Proof-of-Graduation with a signature of recognized University. This approach helps to ease hiring process, with an employer making a query to Hyperledger Iroha to get the acquired skills and competence of the potential employee.

Cross-Border Asset Transfers

Hyperledger Iroha provides fast and clear trade and settlement rules using multi-signature accounts and atomic exchange. Asset management is easy as in centralized systems while providing necessary security guarantees. By simplifying the rules and commands required to create and transfer assets, we lower the barrier to entry, while at the same time maintaining high-security guarantees.

Example

For example [1], a user might want to transfer the ownership of a car. User haruto has registered owner-asset relationship with a car of sora brand with parameters: {"id": "34322069732074686520616E73776572", "color": "red", "size": "small"}. This ownership is fixed in an underlying database of the system with copies at each validating peer. To perform the transfer operation user haruto creates an offer, i.e. a multi-signature transaction with two commands: transfer to user haru the car identifier and transfer some amount of usd tokens from haru to haruto. Upon receiving the offer haru accepts it by signing the multi-signature transaction, in this case, transaction atomically commits to the system.

Hypeledger Iroha has no built-in token, but it supports different assets from various creators. This approach allows building a decentralized exchange market. For example, the system can have central banks from different countries to issue assets.

[1]Currently not implemented

Financial Applications

Hyperleger Iroha can be very useful in the auditing process. Each information is validated by business rules and is constantly maintained by distinct network participants. Access control rules along with some encryption maintain desired level of privacy. Access control rules can be defined at different levels: user-level, domain-level or system-level. At the user-level privacy rules for a specific individual are defined. If access rules are determined at domain or system level, they are affecting all users in the domain. In Hyperledger Iroha we provide convenient role-based access control rules, where each role has specific permissions.

Transactions can be traced with a local database. Using Iroha-API auditor can query and perform analytics on the data, execute specific audit software. Hyperledger Iroha supports different scenarios for deploying analytics software: on a local computer, or execute code on specific middleware. This approach allows analyzing Big Data application with Hadoop, Apache, and others. Hypeledger Iroha serves as a guarantor of data integrity and privacy (due to the query permissions restriction).

Example

For example, auditing can be helpful in financial applications. An auditor account has a role of the auditor with permissions to access the information of users in the domain without bothering the user. To reduce the probability of account hijacking and prevent the auditor from sending malicious queries, the auditor is typically defined as a multi-signature account, meaning that auditor can make queries only having signatures from multiple separate identities. The auditor can make queries not only to fetch account data and balance but also all transactions of a user, e.g. all transfers of user haruto in domain konoha. To efficiently analyze data of million users each Iroha node can work in tandem with analytics software.

Multi-signature transactions are a powerful tool of Hyperledger Iroha that can disrupt tax system. Each transaction in a certain domain can be as a multi-signature transaction, where one signature comes from the user (for example asset transfer) and the second signature comes from special taxing nodes. Taxing nodes will have special validation rules written using Iroha-API, e.g. each purchase in the certified stores must pay taxes. In other words, Iroha a valid purchase transaction must contain two commands: money transfer(purchase) to the store and money transfer(tax payment) to the government.

Identity Management

Hyperledger Iroha has an intrinsic support for identity management. Each user in the system has a uniquely identified account with personal information, and each transaction is signed and associated with a certain user. This makes Hyperledger Iroha perfect for various application with KYC (Know Your Customer) features.

Example

For example, insurance companies can benefit from querying the information of user’s transaction without worrying about the information truthfulness. Users can also benefit from storing personal information on a blockchain since authenticated information will reduce the time of claims processing. Imagine a situation where a user wants to make a hard money loan. Currently, pre-qualification is a tedious process of gathering information about income, debts and information verification. Each user in Hyperledger Iroha has an account with verified personal information, such as owning assets, job positions, and debts. User income and debts can be traced using query GetAccountTransactions, owning assets using query GetAccountAssets and job positions using GetAccountDetail. Each query returns verified result reducing the processing time of hard money loan will take only a few seconds. To incentivize users to share personal information, various companies can come up with business processes. For example, insurance companies can create bonus discounts for users making fitness activities. Fitness applications can push private Proof-of-Activity to the system, and the user can decide later to share information with insurance companies using GrantPermission with permission can_get_my_acc_detail.

Supply Chain

Governance of a decentralized system and representing legal rules as a system’s code is an essential combination of any supply chain system. Certification system used in Hyperledger Iroha allows tokenization of physical items and embedding them into the system. Each item comes with the information about “what, when, where and why”.

Permission systems and restricted set of secure core commands narrows the attack vector and provides effortlessly a basic level of privacy. Each transaction is traceable within a system with a hash value, by the credentials or certificates of the creator.

Example

Food supply chain is a shared system with multiple different actors, such as farmers, storehouses, grocery stores, and customers. The goal is to deliver food from a farmer’s field to the table of a customer. The product goes through many stages, with each stage recorded in shared space. A customer scans a code of the product via a mobile device, in which an Iroha query is encoded. Iroha query provides a full history with all stages, information about the product and the farmer.

For example, gangreen is a registered farmer tomato asset creator, he serves as a guarantor tokenizing physical items, i.e. associating each tomato with an Iroha tomato item. Asset creation and distribution processes are totally transparent for network participants. Iroha tomato goes on a journey through a multitude of vendors to finally come to user chad.

We simplified asset creation to just a single command CreateAsset without the need to create complex smart contracts. One the major advantages of Hyperledger Iroha is in its ease, that allows developers to focus on the provided value of their applications.

Fund Management

With the support of multisignature transactions it is possible to maintain a fund by many managers. In that scheme investment can only be made after the confirmation of the quorum participants.

Example

The fund assets should be held at one account. Its signatories should be fund managers, who are dealing with investments and portfolio distributions. That can be added via AddSignatory command. All of the assets should be held within one account, which signatories represent the fund managers. Thus the concrete exchanges can be performed with the multisignature transaction so that everyone will decide on a particular financial decision. The one may confirm a deal by sending the original transaction and one of managers’ signature. Iroha will maintain the transaction sending so that the deal will not be completed until it receives the required number of confirmation, which is parametrized with the transaction quorum parameter.

Join the Community

First off, thanks for taking the time to contribute!

The following is a short set of guidelines for contributing to Iroha.

How Can I Contribute?

Translating Documentation

Here you can translate Iroha documentation into your language – community will be grateful for your help! Instructions are included – just follow the link to the repository.

Reporting Bugs

Bug is an error, design flaw, failure or fault in Iroha that causes it to produce an incorrect or unexpected result, or to behave in unintended ways.

Bugs are tracked as GitHub issues (this is the preferred option) or as JIRA issues (if it is convenient to you). in Hyperledger Jira.

If you decide to go with the GitHub issues, just click on this link and follow the instructions in the template.

To submit a bug, create new issue and include these details:

Field What to enter
Project Iroha (IR)
Issue Type Bug
Summary Essence of the problem
Description What the issue is about; if you have any logs, please provide them
Priority You can use Medium though if you see the issue as a high priority, please choose that
Environment Your OS, device’s specs, Virtual Environment if you use one, version of Iroha etc.

Reporting Vulnerabilities

While we try to be proactive in preventing security problems, we do not assume they?ll never come up.

It is standard practice to responsibly and privately disclose to the vendor (Hyperledger organization) a security problem before publicizing, so a fix can be prepared, and damage from the vulnerability minimized.

Before the First Major Release (1.0) all vulnerabilities are considered to be bugs, so feel free to submit them as described above. After the First Major Release please utilize a bug bounty program here in order to submit vulnerabilities and get your reward.

In any case ? feel free to reach to any of existing maintainers in Rocket.Chat private messages or in an e-mail (check CONTRIBUTORS.md file) if you want to discuss whether your discovery is a vulnerability or a bug.

Suggesting Improvements

An improvement is a code or idea, which makes existing code or design faster, more stable, portable, secure or better in any other way.

Improvements are tracked as GitHub issues (this is the preferred option) or as JIRA improvements.

Again, if you choose GitHub issues, just click on this link and follow the instructions in the template.

To submit a new improvement in JIRA, create new issue and include these details:

Field What to enter
Project Iroha (IR)
Issue Type Improvement
Summary Essence of the idea
Description What the idea is about; if you have any code suggestions, you are welcome to add them here
Priority You can use Medium
Assign You can assign the task to yourself if you are planning on working on it

Asking Questions

A question is any discussion that is typically neigher a bug, nor feature request or improvement. If you have a question like “How do I do X?” - this paragraph is for you.

Please post your question in your favourite messenger so members of the community could help you. You can also help others!

Your First Code Contribution

Read our C++ Style Guide and start with checking out the GitHub board or the beginner-friendly issues in JIRA with good-first-issue label. Indicate somehow that you are working on this task: get in touch with maintainers team, community or simply assign this issue to yourself.

Pull Requests

  • Fill in the required template
  • End all files with a newline
  • Write tests for new code. Test coverage for new code must be at least 70%
  • Every pull request should be reviewed and get at least two approvals from maintainers team. Check who is a current maintainer in MAINTAINERS.md file
  • When you’ve finished work make sure that you’ve got all passing CI checks ? after that squash and merge your pull request
  • Follow the C++ Style Guide
  • Follow the Git Style Guide
  • Document new code based on the Documentation Styleguide
  • When working with PRs from forks check this manual

Styleguides

Git Style Guide

  • Sign-off every commit with DCO: Signed-off-by: $NAME <$EMAIL>. You can do it automatically using git commit -s
  • Use present tense (“Add feature”, not “Added feature”).
  • Use imperative mood (“Deploy docker to…” not “Deploys docker to…”).
  • Write meaningful commit message.
  • Limit the first line of commit message to 50 characters or less
  • First line of commit message must contain summary of work done, second line must contain empty line, third and other lines can contain list of commit changes

C++ Style Guide

Documentation Styleguide

  • Use Doxygen.
  • Document all public API: methods, functions, members, templates, classes…

FAQ

I’m new. Where to start?

Hello, newcomer! You are very welcome :) There are 2 ways for you to start with Iroha:

  1. You can see what Iroha is an how it works by building a simple example network following our Getting Started Guide
  2. You can get acquainted with the core concepts of Iroha and start building your own Iroha network

Now you have your Iroha blockchain! Congratulations! If you have any questions on it, do not hesitate to contact our community here: https://chat.hyperledger.org/channel/iroha

What type of data can be transferred?

Hyperleder Iroha allows you to send not only assets (you might get such impression due to a highly developed set of commands and queries for serving such assets) but any data that will be stored in the chain as well.

The current implementation provides that opportunity at least via SetAccountDetail command and GetAccountDetail query.

Can mobile device be a node?

There are two options depending on what you mean by mobile device.

If we are speaking about ARM-based hardware with some linux onboard (like Raspberry PI) or rooted Android device, then it is possible to launch Iroha as a node (a peer within a network) on that device. In that case, Iroha will run as a platform-native binary.

If we are speaking about default iOS or Android device with untouched factory shell (GUI), then it is generally not possible and we are not providing any instructions regarding this. Though you still can create mobile applications that use Iroha. They will be Iroha clients and would not serve as peers.

In order to run Iroha on ARM device you have to build it on the target platform. Building Iroha requires notable amount of RAM - for 32-bit ARM host you will need 8GB RAM. The build can be performed inside Docker container. To prepare the container you will need to:

  1. Clone Iroha git repo: https://github.com/hyperledger/iroha
  2. Do docker build -t iroha-build-env . being in iroha/docker/develop
  3. Run the newly built container and build there Iroha itself

Please do not forget to mount a folder with Iroha git repository to the container

What is the throughput (TPS)? Are there any performance test results?

The efficiency of your Iroha network will depend on the configuration, hardware and number of nodes. You are welcome to try out the load test in test/load directory and report the results.