Duniter v2s

A rewriting of Duniter based on Substrate framework.

duniter-v2s is under active development, only a test network called "ĞDev" is deployed.

Use

Join ĞDev network

The easiest way is to use the docker image.

Minimal command to deploy a temporary mirror peer:

docker run -it -p9944:9944 -e DUNITER_CHAIN_NAME=gdev duniter/duniter-v2s:v0.1.0 --tmp --execution=Wasm

To go further, read How to deploy a permanent mirror node on ĞDev network.

Create your local blockchain

It can be useful to deploy your local blockchain, for instance to have a controled environement to develop/test an application that interact with the blockchain.

docker run -it -p9944:9944 duniter/duniter-v2s:v0.1.0 --tmp

Or use the docker-compose.yml at the root of this repository.

Control when your local blockchain should produce blocks

By default, your local blockchain produce a new block every 6 seconds, which is not practical in some cases.

You can decide when to produce blocks with the cli option --sealing, , there are 2 possible modes:

• --sealing=instant: produce a block immediately upon receiving a transaction into the transaction pool
• --sealing=manual: produce a block upon receiving an RPC request (method engine_createBlock).

Autocompletion

See autocompletion.

Test

Test a specific commit

At each commit on master, an image with the tag debug-sha-******** is published, where ******** corresponds to the first 8 hash characters of the commit.

Usage:

docker run -it -p9944:9944 --name duniter-v2s duniter/duniter-v2s:debug-sha-b836f1a6

Then open https://polkadot.js.org/apps/?rpc=ws%3A%2F%2F127.0.0.1%3A9944 in a browser.

Enable detailed logging:

docker run -it -p9944:9944 --name duniter-v2s \
  -e RUST_LOG=debug \
  -e RUST_BACKTRACE=1 \
  -lruntime=debug \
  duniter/duniter-v2s:debug-sha-b836f1a6

Contribute

Before any contribution, please read carefully the CONTRIBUTING file and our git conventions.

Setup your dev environment

First, complete the basic setup instructions.

Build

NOTE: You must first follow the instructions in the [Setup] section (#setup).

Use the following command to build the node without launching it:

cargo build

Run

Use Rust's native cargo command to build and launch the node:

cargo run -- --dev --tmp

This will deploy a local blockchain with test accounts (Alice, Bob, etc) in the genesis.

Single-Node Development Chain

This command will start the single-node development chain with persistent state:

./target/debug/duniter --dev --tmp

Then open https://polkadot.js.org/apps/?rpc=ws%3A%2F%2F127.0.0.1%3A9944 in a browser.

Start the development chain with detailed logging:

RUST_LOG=debug RUST_BACKTRACE=1 ./target/debug/duniter -lruntime=debug --dev

Multi-Node Local Testnet

If you want to see the multi-node consensus algorithm in action, refer to our Start a Private Network tutorial.

Purge previous local testnet

./target/debug/duniter purge-chain --base-path /tmp/alice --chain local
./target/debug/duniter purge-chain --base-path /tmp/bob --chain local

Start Alice's node

./target/debug/duniter \
  --base-path /tmp/alice \
  --chain local \
  --alice \
  --port 30333 \
  --ws-port 9945 \
  --rpc-port 9933 \
  --node-key 0000000000000000000000000000000000000000000000000000000000000001 \
  --validator

Start Bob's node

./target/debug/duniter \
  --base-path /tmp/bob \
  --chain local \
  --bob \
  --port 30334 \
  --ws-port 9946 \
  --rpc-port 9934 \
  --validator \
  --bootnodes /ip4/127.0.0.1/tcp/30333/p2p/12D3KooWEyoppNCUx8Yx66oV9fJnriXwCcXwDDUA2kj6vnc6iDEp

Project Structure

A Substrate project such as this consists of a number of components that are spread across a few directories.

Node

A blockchain node is an application that allows users to participate in a blockchain network. Substrate-based blockchain nodes expose a number of capabilities:

• Networking: Substrate nodes use the libp2p networking stack to allow the nodes in the network to communicate with one another.
• Consensus: Blockchains must have a way to come to consensus on the state of the network. Substrate makes it possible to supply custom consensus engines and also ships with several consensus mechanisms that have been built on top of Web3 Foundation research.
• RPC Server: A remote procedure call (RPC) server is used to interact with Substrate nodes.

There are several files in the node directory - take special note of the following:

• chain_spec.rs: A chain specification is a source code file that defines a Substrate chain's initial (genesis) state. Chain specifications are useful for development and testing, and critical when architecting the launch of a production chain. Take note of the development_chain_spec and testnet_genesis functions, which are used to define the genesis state for the local development chain configuration. These functions identify some well-known accounts and use them to configure the blockchain's initial state.
• service.rs: This file defines the node implementation. Take note of the libraries that this file imports and the names of the functions it invokes. In particular, there are references to consensus-related topics, such as the longest chain rule, the Babe block authoring mechanism and the GRANDPA finality gadget.

After the node has been built, refer to the embedded documentation to learn more about the capabilities and configuration parameters that it exposes:

./target/debug/duniter --help

Runtime

In Substrate, the terms "runtime" and "state transition function" are analogous - they refer to the core logic of the blockchain that is responsible for validating blocks and executing the state changes they define. The Substrate project in this repository uses the FRAME framework to construct a blockchain runtime. FRAME allows runtime developers to declare domain-specific logic in modules called "pallets". At the heart of FRAME is a helpful macro language that makes it easy to create pallets and flexibly compose them to create blockchains that can address a variety of needs.

Review the FRAME runtime implementation included in this template and note the following:

• This file configures several pallets to include in the runtime. Each pallet configuration is defined by a code block that begins with impl $PALLET_NAME::Config for Runtime.
• The pallets are composed into a single runtime by way of the construct_runtime! macro, which is part of the core FRAME Support library.

Pallets

The runtime in this project is constructed using many FRAME pallets that ship with the core Substrate repository and a template pallet that is defined in the pallets directory.

A FRAME pallet is compromised of a number of blockchain primitives:

• Storage: FRAME defines a rich set of powerful storage abstractions that makes it easy to use Substrate's efficient key-value database to manage the evolving state of a blockchain.
• Dispatchables: FRAME pallets define special types of functions that can be invoked (dispatched) from outside of the runtime in order to update its state.
• Events: Substrate uses events to notify users of important changes in the runtime.
• Errors: When a dispatchable fails, it returns an error.
• Config: The Config configuration interface is used to define the types and parameters upon which a FRAME pallet depends.