JesseAbram / Chance

The Unlicense
0 stars 2 forks source link

Substrate Node Template

A new FRAME-based Substrate node, ready for hacking :rocket:

Local Development

Follow these steps to prepare a local Substrate development environment :hammer_and_wrench:

Simple Setup

Install all the required dependencies with a single command (be patient, this can take up to 30 minutes).

curl https://getsubstrate.io -sSf | bash -s -- --fast

Manual Setup

Find manual setup instructions at the Substrate Developer Hub.

Build

Once the development environment is set up, build the node template. This command will build the Wasm and native code:

cargo build --release

Run

Single Node Development Chain

Purge any existing dev chain state:

./target/release/node-template purge-chain --dev

Start a dev chain:

./target/release/node-template --dev

Or, start a dev chain with detailed logging:

RUST_LOG=debug RUST_BACKTRACE=1 ./target/release/node-template -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.

Template 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:

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

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

./target/release/node-template --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:

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:

Run in Docker

First, install Docker and Docker Compose.

Then run the following command to start a single node development chain.

./scripts/docker_run.sh

This command will firstly compile your code, and then start a local development network. You can also replace the default command (cargo build --release && ./target/release/node-template --dev --ws-external) by appending your own. A few useful ones are as follow.

# Run Substrate node without re-compiling
./scripts/docker_run.sh ./target/release/node-template --dev --ws-external

# Purge the local dev chain
./scripts/docker_run.sh ./target/release/node-template purge-chain --dev

# Check whether the code is compilable
./scripts/docker_run.sh cargo check