hardhat-api-builder

Autogenerate your Typescript bindings so you can integrate your contracts with a dApp easily

What

This is a simple plugin to auto-generate an API for solidity files. The plugin will log all public functions to the console with the logapi command, or it can generate typescript API bindings with the tsgen command.

Installation

npm install hardhat-api-builder --save-dev

Import the plugin in your hardhat.config.js:

require("hardhat-api-builder");

Or if you are using TypeScript, in your hardhat.config.ts:

import "hardhat-api-builder";

Tasks

This plugin adds the following tasks to Hardhat:

logapi

npx hardhat logapi --contract MyContractName

This will log all public and external functions and their parameters to the console, for example:

This will log the following output:

------------------------------------------------------
Logging API for: MyContractName
------------------------------------------------------
Transfer(address, address, uint256)
balanceOf(address)
burn(uint256)
getApproved(uint256)
getRoleAdmin(bytes32)
grantRole(bytes32, address)
hasRole(bytes32, address)
isApprovedForAll(address, address)
name()
ownerOf(uint256)
renounceRole(bytes32, address)
revokeRole(bytes32, address)
safeMint(address, string)
safeTransferFrom(address, address, uint256)

...

tsgen

npx hardhat tsgen --contract MyContractName

This will autogenate a MyContractName.ts file which contains Typescript bindings for every public and external method in your contract, as well as a MyContractName_abi.json file. With these two files you can simply copy and paste them into your dapp so you can interact with your smart contract.

The generated JSON file will contain the following:

import { BigNumber, ethers, providers } from "ethers";
import contract from "./BountyQuestion_abi.json";

const contractAddress = "<DEPLOYED_CONTRACT_ADDRESS_HERE>";
const abi = contract;

export default class BountyQuestion {
  bountyQuestion: any;

  constructor(provider: providers.Web3Provider) {
    this.bountyQuestion = new ethers.Contract(contractAddress, abi, provider);
  }

  async DEFAULT_ADMIN_ROLE() {
    return await this.bountyQuestion.DEFAULT_ADMIN_ROLE();
  }

  ...

Plugin Devleopment

first install the depedencies:

npm install

check the the Hardhat Plugin Development Guide to learn how to build a plugin.

to build, run:

npm run build