首页 > 解决方案 > 从 Flutter 为 Firebase 身份验证设置自定义声明

问题描述

我正在为应用程序使用Firebase身份验证,但作为用户创建的一部分,我需要设置一些自定义声明。

我编写了一个云函数来在创建用户时设置声明:

    const functions = require('firebase-functions');
    const admin = require('firebase-admin');
    admin.initializeApp(functions.config().firebase);

    // On sign up.
    exports.processSignUp = functions.auth.user().onCreate(user => {

    let customClaims;

    // Set custom user claims on this newly created user.
    return admin.auth().setCustomUserClaims(user.uid, {
            'https://hasura.io/jwt/claims': {
                'x-hasura-default-role': 'user',
                'x-hasura-allowed-roles': ['user'],
                'x-hasura-user-id': user.uid
            }
        })
        .then(() => {
            // Update real-time database to notify client to force refresh.
            const metadataRef = admin.database().ref("metadata/" + user.uid);
            // Set the refresh time to the current UTC timestamp.
            // This will be captured on the client to force a token refresh.
            return metadataRef.set({
                refreshTime: new Date().getTime()
            });
        })
        .then(() => {
            return admin.auth().getUser(user.uid);
        })
        .then(userRecord => {
            console.log(userRecord);
            return userRecord.toJSON();

        })
        .catch(error => {
            console.log(error);
        });
});

当我将 userRecord 打印到控制台时,我可以看到自定义声明设置正确。

然后在颤抖中,我从创建的用户那里获得了令牌,但它似乎没有附加自定义声明。

我正在使用此代码创建用户并在颤动中打印声明

    Future<FirebaseUser> signUp({String email, String password}) async {
    final FirebaseUser user = (await auth.createUserWithEmailAndPassword(
      email: email,
      password: password,
    )).user;

    IdTokenResult result = await (user.getIdToken(refresh: true));
    print('claims : ${result.claims}');

    return user;
  }

如果我在 jwt 调试器中检查令牌本身,我可以看到它没有得到自定义声明。设置声明后,我是否需要一些额外的步骤来尝试获取更新的令牌?我试过了user.reload()user.getIdToken(refresh: true)但他们似乎没有帮助。

关于如何获取具有自定义声明的令牌的任何想法?

标签: flutterfirebase-authenticationjwtgoogle-cloud-functionsjwt-auth

解决方案


为了将来参考,我设法按照 Doug 的建议来解决这个问题。

这是我的 firebase sdk 管理功能。

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp();

const firestore = admin.firestore();
const settings = {timestampsInSnapshots: true};
firestore.settings(settings);


// On sign up.
exports.processSignUp = functions.auth.user().onCreate(async user => {

// Check if user meets role criteria:
// Your custom logic here: to decide what roles and other `x-hasura-*` should the user get
let customClaims;
// Set custom user claims on this newly created user.

return admin.auth().setCustomUserClaims(user.uid, {
    'https://hasura.io/jwt/claims': {
    'x-hasura-default-role': 'user',
    'x-hasura-allowed-roles': ['user'],
    'x-hasura-user-id': user.uid
}
  })
.then(async () => {
    await firestore.collection('users').doc(user.uid).set({
        createdAt: admin.firestore.FieldValue.serverTimestamp()
    });
 })
 .catch(error => {
    console.log(error);
 });
});

然后在事情的扑朔迷离的一面

Future<FirebaseUser> signUp({String email, String password}) async {
    final FirebaseUser user = (await auth.createUserWithEmailAndPassword(
      email: email,
      password: password,
    )).user;
    currentUser = user;

    await waitForCustomClaims();
    return user;
}

Future waitForCustomClaims() async {
    DocumentReference userDocRef = 
    Firestore.instance.collection('users').document(currentUser.uid);
    Stream<DocumentSnapshot> docs = userDocRef.snapshots(includeMetadataChanges: false);

    DocumentSnapshot data = await docs.firstWhere((DocumentSnapshot snapshot) => snapshot?.data !=null && snapshot.data.containsKey('createdAt'));  
    print('data ${data.toString()}');

    IdTokenResult idTokenResult = await (currentUser.getIdToken(refresh: true));
    print('claims : ${idTokenResult.claims}');
}

希望这将帮助其他希望做类似的人。


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