Play Substrate

Runtime modules

• Template
• Proof of Existence
• Coin flip game
• Offchain worker (unsigned transaction)
• Offchain worker (signed transaction)
• Weight demo
• Data type
• Genesis config demo

A new FRAME-based Substrate node, ready for hacking.

Build

Install Rust:

curl https://sh.rustup.rs -sSf | sh

Initialize your Wasm Build environment:

./scripts/init.sh

Build Wasm and native code:

cargo build --release

Run

Single Node Development Chain

Purge any existing developer chain state:

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

Start a development chain with:

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

Detailed logs may be shown by running the node with the following environment variables set: RUST_LOG=debug RUST_BACKTRACE=1 cargo run -- --dev.

Multi-Node Local Testnet

If you want to see the multi-node consensus algorithm in action locally, then you can create a local testnet with two validator nodes for Alice and Bob, who are the initial authorities of the genesis chain that have been endowed with testnet units.

Optionally, give each node a name and expose them so they are listed on the Polkadot telemetry site.

You'll need two terminal windows open.

We'll start Alice's substrate node first on default TCP port 30333 with her chain database stored locally at /tmp/alice. The bootnode ID of her node is QmRpheLN4JWdAnY7HGJfWFNbfkQCb6tFf4vvA6hgjMZKrR, which is generated from the --node-key value that we specify below:

cargo run -- \
  --base-path /tmp/alice \
  --chain=local \
  --alice \
  --node-key 0000000000000000000000000000000000000000000000000000000000000001 \
  --telemetry-url 'ws://telemetry.polkadot.io:1024 0' \
  --validator

In the second terminal, we'll start Bob's substrate node on a different TCP port of 30334, and with his chain database stored locally at /tmp/bob. We'll specify a value for the --bootnodes option that will connect his node to Alice's bootnode ID on TCP port 30333:

cargo run -- \
  --base-path /tmp/bob \
  --bootnodes /ip4/127.0.0.1/tcp/30333/p2p/QmRpheLN4JWdAnY7HGJfWFNbfkQCb6tFf4vvA6hgjMZKrR \
  --chain=local \
  --bob \
  --port 30334 \
  --telemetry-url 'ws://telemetry.polkadot.io:1024 0' \
  --validator

Additional CLI usage options are available and may be shown by running cargo run -- --help.

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

Advanced: Generate Your Own Substrate Node Template

A substrate node template is always based on a certain version of Substrate. You can inspect it by opening Cargo.toml and see the template referred to a specific Substrate commit( rev field), branch, or version.

You can generate your own Substrate node-template based on a particular Substrate version/commit by running following commands:

# git clone from the main Substrate repo
git clone https://github.com/paritytech/substrate.git
cd substrate

# Switch to a particular branch or commit of the Substrate repo your node-template based on
git checkout <branch/tag/sha1>

# Run the helper script to generate a node template.
# This script compiles Substrate and takes a while to complete. It takes a relative file path
#   from the current dir. to output the compressed node template.
.maintain/node-template-release.sh ../node-template.tar.gz

Noted though you will likely get faster and more thorough support if you stick with the releases provided in this repository.