Firebase 将匿名用户帐户转换为永久帐户错误

Question

使用 Firebase for web 我可以成功创建一个匿名用户。我还可以创建一个新的电子邮件/密码用户。但是当尝试将匿名用户转换为电子邮件/密码用户时，我收到错误:

auth/provider-already-linked
User can only be linked to one identity for the given provider.

Firebase 在此处的“将匿名帐户转换为永久帐户”部分下记录了该过程:
https://firebase.google.com/docs/auth/web/anonymous-auth

这是帐户链接代码。匿名用户已登录。

return firebase.auth().createUserWithEmailAndPassword(email, password).then(newUser => {

    // Credential is being successfully retrieved. Note "any" workaround until typescript updated.
    let credential = (<any>firebase.auth.EmailAuthProvider).credential(email, password);

    firebase.auth().currentUser.link(credential)
        .then(user => { return user; })
        .catch(err => console.log(err)); // Returns auth/provider-already-linked error.
});

Answer 1

您不应调用 createUserWithEmailAndPassword升级匿名用户。这将注册一个新用户，退出当前登录的匿名用户。

您只需要用户的电子邮件和密码。相反，IDP 提供商(例如谷歌、Facebook)将需要完成他们的完整登录流程，以获取他们的 token 来识别用户。我们建议使用 linkWithPopup 或 linkWithRedirect 不过，对于这些。

例子:

// (Anonymous user is signed in at that point.)

// 1. Create the email and password credential, to upgrade the
// anonymous user.
var credential = firebase.auth.EmailAuthProvider.credential(email, password);

// 2. Links the credential to the currently signed in user
// (the anonymous user).
firebase.auth().currentUser.linkWithCredential(credential).then(function(user) {
  console.log("Anonymous account successfully upgraded", user);
}, function(error) {
  console.log("Error upgrading anonymous account", error);
});

让我知道这是否有效!