bls-wallet/docs/use_bls_wallet_clients.md

# Use BLS Wallet Client

This walkthrough will show you how to submit an ERC20 transfer to the BLS Wallet Aggregator.

## Add bls-wallet-clients

```sh
# npm
npm install bls-wallet-clients
# yarn
yarn add bls-wallet-clients
# deno in example further below
```

## Import

```typescript
import { providers } from "ethers";
import { Aggregator, BlsWalletWrapper, getConfig } from "bls-wallet-clients";
```

### Deno

You can use [esm.sh](https://esm.sh/) or a similar service to get Deno compatible modules.

```typescript
import { providers } from "https://esm.sh/ethers@latest";
import {
  Aggregator,
  BlsWalletWrapper,
  getConfig,
} from "https://esm.sh/bls-wallet-clients@latest";
```

## Get Deployed Contract Addresses

You can find current contract deployments in the [contracts networks folder](../contracts/networks/).
If you would like to deploy locally, see [Local development](./local_development.md).
If you would like to deploy to a remote network, see [Remote development](./remote_development.md).

## Send a transaction

```typescript
import { readFile } from "fs/promises";

// import fetch from 'node-fetch'; // Add this if using nodejs<18
import { ethers, providers } from "ethers";
import { Aggregator, BlsWalletWrapper, getConfig } from "bls-wallet-clients";

// globalThis.fetch = fetch; // Add this if using nodejs<18

// Instantiate a provider via browser extension, such as Metamask
// const provider = new providers.Web3Provider(window.ethereum);
// Or via RPC
const provider = new providers.JsonRpcProvider(
  "https://goerli-rollup.arbitrum.io/rpc"
);
// See https://docs.ethers.io/v5/getting-started/ for more options

// Get the deployed contract addresses for the network.
// Here, we will get the Arbitrum testnet.
// See local_development.md for deploying locally and
// remote_development.md for deploying to a remote network.
const netCfg = await getConfig(
  "../contracts/networks/arbitrum-goerli.json",
  async (path) => readFile(path)
);

// 32 random bytes
const privateKey =
  "0x0001020304050607080910111213141516171819202122232425262728293031";

// Note that if a wallet doesn't yet exist, it will be
// lazily created on the first transaction.
const wallet = await BlsWalletWrapper.connect(
  privateKey,
  netCfg.addresses.verificationGateway,
  provider
);

const erc20Address = netCfg.addresses.testToken; // Or some other ERC20 token
const erc20Abi = ["function mint(address to, uint amount) returns (bool)"];
const erc20 = new ethers.Contract(erc20Address, erc20Abi, provider);

console.log("Contract wallet:", wallet.address);
console.log("Test token:", erc20.address);

const nonce = await wallet.Nonce();
// All of the actions in a bundle are atomic, if one
// action fails they will all fail.
const bundle = wallet.sign({
  nonce,
  actions: [
    {
      // Mint ourselves one test token
      ethValue: 0,
      contractAddress: erc20.address,
      encodedFunction: erc20.interface.encodeFunctionData("mint", [
        wallet.address,
        ethers.utils.parseUnits("1", 18),
      ]),
    },
  ],
});

const aggregator = new Aggregator("https://arbitrum-goerli.blswallet.org");

console.log("Sending bundle to the aggregator");
const addResult = await aggregator.add(bundle);

if ("failures" in addResult) {
  throw new Error(addResult.failures.join("\n"));
}

console.log("Bundle hash:", addResult.hash);

const checkConfirmation = async () => {
  console.log("Checking for confirmation");
  const maybeReceipt = await aggregator.lookupReceipt(addResult.hash);

  if (maybeReceipt === undefined) {
    return;
  }

  console.log("Confirmed in block", maybeReceipt.blockNumber);
  provider.off("block", checkConfirmation);
};

provider.on("block", checkConfirmation);
```

## More

See [clients](../contracts/clients/) for additional functionality.