celo-org / viem

TypeScript Interface for Ethereum

TypeScript Interface for Ethereum

Features

• Abstractions over the JSON-RPC API to make your life easier
• First-class APIs for interacting with Smart Contracts
• Language closely aligned to official Ethereum terminology
• Import your Browser Extension, WalletConnect or Private Key Wallet
• Browser native BigInt, instead of large BigNumber libraries
• Utilities for working with ABIs (encoding/decoding/inspection)
• TypeScript ready (infer types from ABIs and EIP-712 Typed Data)
• First-class support for Anvil, Hardhat & Ganache
• Test suite running against forked Ethereum network

... and a lot more.

Overview

// 1. Import modules.
import { createPublicClient, http } from 'viem';
import { mainnet } from 'viem/chains';

// 2. Set up your client with desired chain & transport.
const client = createPublicClient({
  chain: mainnet,
  transport: http(),
});

// 3. Consume an action!
const blockNumber = await client.getBlockNumber();

Documentation

Head to the documentation to read and learn more about viem.

Community

Check out the following places for more viem-related content:

• Follow @wevm_dev, @jakemoxey, and @awkweb on Twitter for project updates
• Join the discussions on GitHub
• Share your project/organization that uses viem

Support

• GitHub Sponsors
• Gitcoin Grant
• wevm.eth

Sponsors

Contributing

If you're interested in contributing, please read the contributing docs before submitting a pull request.

Authors

• @jxom (jxom.eth, Twitter)
• @tmm (awkweb.eth, Twitter)

License

MIT License

viem's Issues

bug: `contract.simulate` does not accept `feeCurrency` field

Is there an existing issue for this?

• I have searched the existing issues

Package Version

2.7.9

Current Behavior

This code snippet shows an error (red squiggly line) under feeCurrency:

const transactionSimulation = await contract.simulate.transfer(
        [cUSD_CONTRACT_ADDRESS, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
);

The error message is:

Object literal may only specify known properties, and 'feeCurrency' does not exist in type 'Omit<SimulateContractParameters<readonly ...

But the same code as contract.write.transfer accepts the feeCurrency

const transactionReceipt = await contract.write.transfer(
        [cUSD_CONTRACT_ADDRESS, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
    );

Expected Behavior

simulate and WalletClient calls should accept the same fields.

Viem recommends that most contract calls or transactions are first simulated

Warning: The write internally sends a transaction – it does not validate if the contract write will succeed (the contract may throw an error). It is highly recommended to simulate the contract write with `contract.simulate` before you execute it.

Steps To Reproduce

import {
    createPublicClient,
    createWalletClient,
    http,
    parseEther,
    parseGwei,
    Address,
    getContract,
    erc20Abi,
    parseUnits,
    formatUnits,
} from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { celoAlfajores } from "viem/chains";
import {
    PRIVATE_KEY,
    RECIPIENT,
    cUSD_CONTRACT_ADDRESS,
    USDC_CONTRACT_ADDRESS,
    USDC_ADAPTER_ADDRESS,
} from "./constants";

/**
 * Boilerplate to create a viem client and viem-compatible wallet
 */
const read = createPublicClient({
    chain: celoAlfajores,
    transport: http(),
});
const write = createWalletClient({
    chain: celoAlfajores, // Celo testnet
    transport: http(),
});
const sender = privateKeyToAccount(`0x${PRIVATE_KEY}`);

/**
 *  Set up ERC20 contract
 */
const contract = getContract({
    address: cUSD_CONTRACT_ADDRESS,
    abi: erc20Abi,
    client: { public: read, wallet: write },
});
const [symbol, decimals, tokenBalance] = await Promise.all([
    contract.read.symbol(),
    contract.read.decimals(),
    contract.read.balanceOf(["0xcEe284F754E854890e311e3280b767F80797180d"]),
]);

/**
 * Makes a transaction to transfer ERC20 tokens using a fee currency
 */
async function erc20Transfer() {
    console.log(`Initiating fee currency transaction...`);
    console.log(`${symbol} balance of ${sender}: ${formatUnits(tokenBalance, decimals)}`);

    const transactionSimulation = await contract.simulate.transfer(
        [RECIPIENT, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
    );
    const transactionReceipt = await contract.write.transfer(
        [RECIPIENT, parseUnits("0.01", decimals)],
        { account: sender, feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1" }
    );
    console.log(transactionReceipt);
}

erc20Transfer().catch((err) => {
    console.error("An error occurred:", err);
});

Link to Minimal Reproducible Example (StackBlitz, CodeSandbox, GitHub repo etc.)

https://github.com/celo-org/feecurrency/blob/main/viem.ts

Anything else?

No response

Related

• celo-org/developer-tooling#128
  - celo-org/feecurrency demo repo

Add celo gas fee estimator

Is there an existing issue for this?

• I have searched the existing issues

Package Version

1.0.0

Current Behavior

when using feeCurrency it is necessary to lookup gasPrice by hand as the automatic way does not factor in feeCurrency

Expected Behavior

Add a celo estimateFeesPerGas function

internally this should call eth_gasPrice with feeCurrency as a param

should return

return {
      maxFeePerGas,
      maxPriorityFeePerGas,
    } as EstimateFeesPerGasReturnType<type>   

https://github.com/wagmi-dev/viem/blob/5c95fafceffe7f399b5b5ee32119e2d78a0c8acd/src/actions/public/estimateFeesPerGas.ts#L130-L137

Steps To Reproduce

No response

Link to Minimal Reproducible Example (StackBlitz, CodeSandbox, GitHub repo etc.)

No response

Anything else?

No response

viem-op extensions compatibility with cel2

l1 fees (absent on cel2)

If we deploy a contract with the GasPriceOracle Interface that returns 0 then any function from viem that calls L1fees will still work for cel2.

#306

fault proof / game related

• unclear so far how functions that related to DisputeGameFactoryProxy contract will be affected

Remove `feeCurrency`, `gatewayFee`, and `gatewayFeeRecipient` properties from transaction receipts

Is there an existing issue for this?

• I have searched the existing issues

Package Version

1.16.0

Description

I build the following CIP-42 transaction.

Note that I specify cUSD as the fee currency:

const transactionHash = await client.sendTransaction({
        account, // Sender
        to: "0x70997970c51812dc3a010c7d01b50e0d17dc79c8", // Recipient (illustrative address)
        value: parseEther("0.01"), // 0.01 CELO
        feeCurrency: "0x874069Fa1Eb16D44d622F2e0Ca25eeA172369bC1", // cUSD fee currency
        maxFeePerGas: parseGwei("10"), // Special field for dynamic fee transaction type (EIP-1559)
        maxPriorityFeePerGas: parseGwei("10"), // Special field for dynamic fee transaction type (EIP-1559)
    });

Source: 0xarthurxyz/txtypes

When I parse (and format) the transaction receipt with:

const transactionReceipt = await publicClient.waitForTransactionReceipt({
        hash: await transactionHash,
});

printFormattedTransactionReceipt(transactionReceipt);

The feeCurrency field is undefined.

Transaction details: {
  type: '0x7c',
  status: 'success',
  transactionHash: '0x9935c26499205b028a2518cfa5a32b7ebf68533deec414c8ded9f91ae5aa5dd8',
  from: '0x303c22e6ef01cba9d03259248863836cb91336d5',
  to: '0x70997970c51812dc3a010c7d01b50e0d17dc79c8',
  feeCurrency: undefined
} 

This is expected, because the feeCurrency, gatewayFee, and gatewayFeeRecipient fields are never included in a transaction receipt. See here where the transaction receipt is defined in the Celo blockchain client.

That means the 3 fields can be removed from the transaction receipt

transactionReceipt: /*#__PURE__*/ defineTransactionReceipt({
    format(
      args: CeloRpcTransactionReceiptOverrides,
    ): CeloTransactionReceiptOverrides {
      return {
-        feeCurrency: args.feeCurrency,
-        gatewayFee: args.gatewayFee ? hexToBigInt(args.gatewayFee) : null,
-        gatewayFeeRecipient: args.gatewayFeeRecipient,
      }
    },
  }),

See Slack discussion with the Blockchain team here.