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Crossmint Auth provides a way to retrieve and update user profile data, such as email, social login metadata, and more.
The user object contains the following information:
  • userId: User’s unique identifier.
  • email: User’s email address.
  • phoneNumber: User’s phone number.
  • google: User’s Google account data.
  • farcaster: User’s Farcaster account data.
Google Account data contains:
  • name: User’s Google display name.
  • picture: User’s Google profile picture URL.
Farcaster Account data contains:
  • fid: User’s Farcaster ID.
  • username: User’s Farcaster username.
  • bio: User’s Farcaster bio.
  • displayName: User’s Farcaster display name.
  • pfpUrl: User’s Farcaster profile image URL.
  • custody: User’s FID custody address.
  • verifications: List of the user’s verified addresses.

​
Reading User Data

This API requires the users.read scope.
  • Server side: Requires a server-side API key.
  • Client side: Requires a client-side API key, and a logged in user.

​
Server-side

For server-side operations, use the @crossmint/server-sdk that provides a getUser function to fetch user information. 
import { createCrossmint, CrossmintAuth } from "@crossmint/server-sdk";

const crossmint = createCrossmint({ apiKey: SERVER_API_KEY });
const crossmintAuth = CrossmintAuth.from(crossmint);

async function getUser(userId: string) {
    try {
        const user = await crossmintAuth.getUser(userId);
        console.log("User data:", user);
    } catch (error) {
        console.error("Error fetching user data:", error);
    }
}

​
Response Format

{
    "userId": "123",
    "email": "test@test.com", // Optional (if user was created with email)
    "phoneNumber": "123456789", // Optional (if user was created with phone number)
    "google": {
        "name": "John Doe",
        "picture": "https://example.com/picture.jpg"
    },
    "farcaster": {
        "fid": "123",
        "username": "johndoe",
        "bio": "Hello, I'm John Doe",
        "displayName": "John Doe",
        "pfpUrl": "https://example.com/pfp.jpg",
        "custody": "0x1234567890123456789012345678901234567890",
        "verifications": ["0x1234567890123456789012345678901234567890"]
    }
}

​
Client-side

Use the useAuth react hook from @crossmint/client-sdk-react-ui to access the user object.
If you would like to use a different framework, contact support
React
import { useAuth } from "@crossmint/client-sdk-react-ui";

function User() {
    const { user } = useAuth();

    if (!user) {
        return <div>Loading user...</div>;
    }

    return (
        <div>
            <h1>User</h1>
            <p>User ID: {user.userId}</p>
            <p>Email: {user.email}</p>
            <p>Phone Number: {user.phoneNumber}</p>
            <p>Google Name: {user.google?.name}</p>
            <p>Google Picture: {user.google?.picture}</p>
            <p>Farcaster FID: {user.farcaster?.fid}</p>
            <p>Farcaster Username: {user.farcaster?.username}</p>
            <p>Farcaster Bio: {user.farcaster?.bio}</p>
            <p>Farcaster Display Name: {user.farcaster?.displayName}</p>
            <p>Farcaster PFP URL: {user.farcaster?.pfpUrl}</p>
            <p>Farcaster Custody: {user.farcaster?.custody}</p>
            <p>Farcaster Verifications: {user.farcaster?.verifications}</p>
        </div>
    );
}
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