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cargo-contract

cargo-contract is a unified CLI tool to develop and deploy ink! smart contracts.

Using cargo-contract, you can create new contracts, check and build existing ones and interact with uploaded contracts on-chain.

Installation​

To start using cargo-contract, ensure that you have your Rust toolchain installed. If you don't have an installed Rust toolchain, you can use Rustup to install one.

Besides using Rust toolchain, cargo-contract requires a C++ compiler installed. You can use any modern version of GCC, Clang or MSVC.

After that, you can install cargo-contract using the following steps:

  1. rustup component add rust-src
  2. cargo install --force --locked cargo-contract

Usage​

To create a new contract use the cargo contract new subcommand: cargo contract new my_contract

After that, a new directory with the name my_contract will be created, with the sample contract inside of it.

To build this sample contract, use the cargo contract build command. This command automatically invokes Cargo, Rust's package manager with the necessary parameters to produce WASM blob. After generating WASM code, some ink!-specific optimizations are also applied automatically.

Deployment​

Assuming your build process was a success, we can proceed with uploading your code.

Using cargo contract upload subcommand, we can upload WASM blob to the specified chain (local development chain by default): cargo contract upload --suri //Alice. In this case, we are using "Alice" test identity.

After running the upload subcommand, cargo-contract provides us with the code hash, which we can use to instantiate our smart contract.

Smart contract instantiation is required to "initialize" our contract by calling its constructor method:

cargo contract instantiate \
       --constructor new \
       --args false \
       --suri //Alice \
       --code-hash 0xABC...

After that, cargo-contract provides us with the contract address, which we can use to call smart contract methods using the call subcommand:

cargo contract call \
       --contract 0x123... \
       --message hello \
       --suri //Alice