ethcontract-rs

Crate used for generating code for Ethereum smart contracts. It provides a function procedural macro that generates safe bindings for contract interaction based on the contract ABI.

Getting Started

Add a dependency to the ethcontract crate in your Cargo.toml:

toml [dependencies] ethcontract = "..."

Then generate a struct for interacting with the smart contract with a type-safe API:

rust ethcontract::contract!("path/to/truffle/build/contract/Contract.json");

This will generate a new struct ContractName with contract generated methods for interacting with contract functions in a type-safe way.

Minimum Supported Rust Version

The minimum supported Rust version is 1.39. This is required for async/await support which is used by one of the examples. Note that the core libraries probably work with some earlier versions of Rust but they are not officially supported or tested.

Generator API

As an alternative to the procedural macro, a generator API is provided for generating contract bindings from build.rs scripts. More information can be found in the ethcontract-generate README.

Running the Examples

In order to run local examples you will additionally need: - NodeJS - Yarn

For all examples, the smart contracts must first be built:

sh cd examples/truffle yarn && yarn build

Truffle Examples

Truffle examples rely on the local truffle development server. In a separate terminal run:

sh cd examples/truffle yarn start

• The async example deploys an ERC20 token and interacts with the contract with various accounts. First start the local development server: sh cargo run --example async

• The generator example (actually a separate crate to be able to have a build script) demonstrates how the generator API can be used for creating type-safe bindings to a smart contract with a build.rs build script. sh cargo run --package examples-generate

• The linked example deploys a library and a contract that links to it and makes a method call. sh cargo run --example linked

Rinkeby Example

There is a provided example that runs with Rinkeby and Infura. Running this example is a little more involved to run because it requires a private key with funds on Rinkeby (for gas) as well as a Infura project ID in order to connect to a node. Parameters are provided to the Rinkeby example by environment variables:

sh export PK="private key" export INFURA_PROJECT_ID="Infura project ID" cargo run --example rinkeby

Sample Contracts Documentation

We added some samples of generated contracts from our sample contract collection gated behind a feature. This feature is only intended to be used for document generation. In order to view the documentation for these contracts you need to first build the contracts and then generate documentation for the crate with the samples feature enabled:

sh (cd examples/truffle; yarn && yarn build) cargo doc --features samples --open

This will open a browser at the documentation root. Look under the samples module for the sample contracts to get a feel for how the generated types look.