Neynar Documentation

Hook for Signing In a User

Connects to the relay server, generates a sign in link to present to the user, and polls the relay server for the user’s Farcaster wallet signature. If you want to build your own sign in component with a custom UI, use the useSignIn hook.

import { useSignIn, QRCode } from '@farcaster/auth-kit';

function App() {
  const {
    signIn,
    url,
    data: { username },
  } = useSignIn({
    onSuccess: ({ fid }) => console.log('Your fid:', fid),
  });

return (
    <div>
      <button onClick={signIn}>Sign In</button>
      {url && (
        <span>
          Scan this: <QRCode uri={url} />
        </span>
      )}
      {username && `Hello, ${username}!`}
    </div>
  );
}

Parameters

Parameter	Type	Description	Default
`timeout`	`number`	Return an error after polling for this long.	`300_000` (5 minutes)
`interval`	`number`	Poll the relay server for updates at this interval.	`1500` (1.5 seconds)
`nonce`	`string`	A random nonce to include in the Sign In With Farcaster message.	None
`notBefore`	`string`	Time when the SIWF message becomes valid. ISO 8601 datetime string.	None
`expirationTime`	`string`	Time when the SIWF message expires. ISO 8601 datetime string.	None
`requestId`	`string`	An optional system-specific ID to include in the SIWF message.	None
`onSuccess`	`function`	Callback invoked when sign in is complete and the user is authenticated.	None
`onStatusResponse`	`function`	Callback invoked when the component receives a status update from the relay server.	None
`onError`	`function`	Error callback function.	None

Returns

{
  signIn: () => void;
  signOut: () => void;
  connect: () => void;
  reconnect: () => void;
  isConnected: boolean;
  isSuccess: boolean;
  isPolling: boolean;
  isError: boolean;
  error: AuthClientError;
  channelToken: string;
  url: string;
  appClient: AppClient;
  data: {
      state: "pending" | "complete";
      nonce: string;
      message: string;
      signature: Hex;
      fid: number;
      username: string;
      bio: string;
      displayName: string;
      pfpUrl: string;
      custody?: Hex;
      verifications?: Hex[];
  },
  validSignature: boolean;
};

Parameter	Description
`signIn`	Call this function following `connect` to begin polling for a signature.
`signOut`	Call this function to clear the AuthKit state and sign out the user.
`connect`	Connect to the auth relay and create a channel.
`reconnect`	Reconnect to the relay and try again. Call this in the event of an error.
`isConnected`	True if AuthKit is connected to the relay server and has an active channel.
`isSuccess`	True when the relay server returns a valid signature.
`isPolling`	True when the relay state is "pending" and the app is polling the relay server for a response.
`isError`	True when an error has occurred.
`error`	`AuthClientError` instance.
`channelToken`	Connect relay channel token.
`url`	Sign in With Farcaster URL to present to the user. Links to the Farcaster client in v1.
`appClient`	Underlying `AppClient` instance.
`data.state`	Status of the sign in request, either "pending" or "complete"
`data.nonce`	Random nonce used in the SIWE message. If you don’t provide a custom nonce as an argument to the hook, you should read this value.
`data.message`	The generated SIWE message.
`data.signature`	Hex signature produced by the user’s Farcaster client app wallet.
`data.fid`	User’s Farcaster ID.
`data.username`	User’s Farcaster username.
`data.bio`	User’s Farcaster bio.
`data.displayName`	User’s Farcaster display name.
`data.pfpUrl`	User’s Farcaster profile picture URL.
`data.custody`	User’s FID custody address.
`data.verifications`	List of user’s verified addresses.
`validSignature`	True when the signature returned by the relay server is valid.