ink! Quickstart Guide

This guide will walk you through setting up a simple ink! project and deploying it to a local development chain. As an example, we will implement a simple PSP22 (similar to ERC20) token contract. The main goal of this repository is to provide you a quickstart template that contains ready to use PSP22 implementation.

Before we start

Before we start, make sure you have the following prerequisites installed:

• Rust and Cargo: https://www.rust-lang.org/tools/install
• Download rust 1.74: rustup toolchain install 1.74
• Install the cargo-contract utils. Detailed instruction on environemnt setup can be found here: https://use.ink/getting-started/setup and here https://github.com/paritytech/cargo-contract?tab=readme-ov-file#installation
• Install substrate-contracts-node https://use.ink/getting-started/setup#installing-substrate-contracts-node

To check what version of rust toolchain you are using, run rustup show and make sure that the default toolchain is set to 1.74.

Executing command cargo contract should print the following output:

Utilities to develop Wasm smart contracts

Usage: cargo contract <COMMAND>

Commands:
  new          Setup and create a new smart contract project
  build        Compiles the contract, generates metadata, bundles both together in a `<name>.contract` file
  check        Check that the code builds as Wasm; does not output any `<name>.contract` artifact to the `target/` directory
  upload       Upload contract code
  instantiate  Instantiate a contract
  call         Call a contract
  encode       Encodes a contracts input calls and their arguments
  decode       Decodes a contracts input or output data (supplied in hex-encoding)
  remove       Remove contract code
  info         Display information about a contract
  help         Print this message or the help of the given subcommand(s)

Options:
  -h, --help     Print help
  -V, --version  Print version

Build the contract

cargo contract build --release

This command will build the following for your contract: a Wasm binary, a metadata file (which contains the contract's ABI) and a .contract file which bundles both. This .contract file can be used to deploy your contract to a chain. If all goes well, you should see a target folder which contains these files:

target/
└── ink
    ├── ink_quickstart_psp22_prv.contract
    ├── ink_quickstart_psp22_prv.json
    └── ink_quickstart_psp22_prv.wasm

For more details about the output files, please refer to the official ink! docs: https://use.ink/getting-started/building-your-contract

Deploy the contract

First start off with a local development chain. This can be done by running the following command: substrate-contracts-node

After that, you should get following output:

2024-01-10 02:43:19.004  INFO main sc_cli::runner: Substrate Contracts Node    
2024-01-10 02:43:19.004  INFO main sc_cli::runner: ✌  version 0.35.0-unknown    
2024-01-10 02:43:19.004  INFO main sc_cli::runner: ❤  by anonymous, 2021-2024    
2024-01-10 02:43:19.004  INFO main sc_cli::runner: 📋 Chain specification: Development    
2024-01-10 02:43:19.004  INFO main sc_cli::runner: 🏷  Node name: perfect-tin-6965    
2024-01-10 02:43:19.004  INFO main sc_cli::runner: 👤 Role: AUTHORITY    
2024-01-10 02:43:19.004  INFO main sc_cli::runner: 💾 Database: RocksDb at /tmp/substratewlqM30/chains/dev/db/full    
2024-01-10 02:43:19.525  INFO main sc_rpc_server: Running JSON-RPC server: addr=127.0.0.1:9944, allowed origins=["*"] 

Remember to not close this terminal window, as it will stop the chain.

After that open https://contracts-ui.substrate.io/ in your browser and connect to the local development chain. In your upper left corner make sure to select the "Local node" option.

After that, click on the "Upload a new contract" button and select the .contract file from the target folder.

Detailed instructions with images can be found here: https://use.ink/getting-started/deploy-your-contract

Interact with the contract

After you have deployed the contract, you can interact with it by clicking on the function name and filling in the required parameters.

More example: https://use.ink/getting-started/calling-your-contract