Neynar Documentation

Prerequisites

Node.js Installed

Ensure you have Nodejs installed on your system. You can download it from Node.js’ official website.

API Key and Mnemonic

Obtain an API key from the dev portal Ensure you have a valid Ethereum mnemonic phrase of the account with a signer associated with the above API key.

Dependencies Installed

Install the required packages:

yarn add siwe viem @neynar/nodejs-sdk

Code Breakdown and Steps

Import Required Libraries

The code begins by importing the necessary libraries:

import { SiweMessage } from "siwe";
import { mnemonicToAccount } from "viem/accounts";
import { NeynarAPIClient, Configuration } from "@neynar/nodejs-sdk";

Define Your Mnemonic

Replace "YOUR_MNEMONIC_HERE" with your Ethereum mnemonic phrase:

const mnemonic = "YOUR_MNEMONIC_HERE";

Convert Mnemonic to Account

The mnemonicToAccount function converts your mnemonic into an account object:

const account = mnemonicToAccount(mnemonic);

Configure Neynar API Client

Replace "YOUR_API_KEY_HERE" with your API key and set the correct base path for the Neynar API:

const config = new Configuration({
  apiKey: "YOUR_API_KEY_HERE",
});

const client = new NeynarAPIClient(config);

Create the SIWE Message

The createSiweMessage function generates a SIWE message with details such as domain, address, and nonce:

async function createSiweMessage(address, statement) {
  const { nonce } = await client.fetchNonce();

  const message = new SiweMessage({
    scheme: "http",
    domain: "localhost:8080",
    address,
    statement,
    uri: "http://localhost:8080",
    version: "1",
    chainId: "1",
    nonce: nonce,
  });

  return message.prepareMessage();
}

Sign and Verify the Message

The fetchSigners function handles the signing process and fetches signers:Note: The address should be the custody_address of the farcaster account (Check custody_address in User API)

async function fetchSigners() {
  const address = account.address;

  let message = await createSiweMessage(
    address,
    "Sign in with Ethereum to the app."
  );

  const signature = await account.signMessage({ message });

  const { signers } = await client.fetchSigners({ message, signature });

  return signers;
}

Execute the Function

Call the fetchSigners function and handle success or errors:

fetchSigners()
  .then((signers) => {
    console.log("\n\nsigners:", signers, "\n\n");
  })
  .catch((error) => {
    console.error("error:", error);
  });

Expected Output

[
  {
    "object": "signer",
    "signer_uuid": "19d0c5fd-9b33-4a48-a0e2-bc7b0555baec",
    "public_key": "0xe4abc135d40f8a6ee216d1a6f2f4e82476dff75f71ea53c5bdebca43f5c415b7",
    "status": "approved",
    "fid": 0
  },
  {
    "object": "signer",
    "signer_uuid": "08c71152-c552-42e7-b094-f510ff44e9cb",
    "public_key": "0xe4cd577123def73295dd9991c589b59b48cdc976b5e83a9ad8d2a13fcfcc0e72",
    "status": "approved",
    "fid": 0
  }
]

For additional help, feel free to contact us.

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Fetch Signers - Backend

Prerequisites

Code Breakdown and Steps

Expected Output

​Related API: List signers

​Prerequisites

​Code Breakdown and Steps

​Expected Output

Related API: List signers

Prerequisites

Code Breakdown and Steps

Expected Output