Firebase getIdToken不起作用

Question

我正在使用来自JavaScript客户端的Firebase身份验证进行测试，并且正在尝试使用客户端文档上的检索ID令牌来检索IDToken

我想我忘记了一些基本的知识。

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The code is just i've seen in other posts and in the documentation. And the result is in the comments.

firebase.auth().onAuthStateChanged(function(user) {
  if (user) {
     console.log(user); // this is shown. Firebase user and provider data
     console.log(user.uid); // Shown
        firebase.auth().user.getIdToken().then(function(idToken) {
           console.log(idToken+'--'); // Nothing happens. No errors and the function not continues
        });
     console.log(user.uid); // Nothing happens
  }
})

Thanks

EDIT:

if I add anything wrong nothing happens too. for example if I add an alert it shows the alert but if I have a mistake, for example alter() not shows any error. Added catch and nothing too

firebase.auth().onAuthStateChanged(function(user) {
  if (user) {
     alter() // Nothing happens and the function stop         
     console.log(user); // this is shown. Firebase user and provider data
     console.log(user.uid); // Shown
        firebase.auth().user.getIdToken().then(function(idToken) {
           console.log(idToken+'--'); // Nothing happens. No errors and the function not continues
        }).catch(function(error) {
            console.log(error+'--'); // Nothing
        });
     console.log(user.uid); // Nothing happens
  }
})

Answer 1

firebase.auth().user没有user在那一刻呢。您必须像这样直接使用userfrom firebase.auth().onAuthStateChanged：

firebase.auth().onAuthStateChanged(function(user) {
    if (user) {
        console.log(user); // It shows the Firebase user
        console.log(firebase.auth().user); // It is still undefined
        user.getIdToken().then(function(idToken) {  // <------ Check this line
           console.log(idToken); // It shows the Firebase token now
        });
    }
});

您只能firebase.auth().user在firebase.auth().onAuthStateChanged完成之后使用并且超出其范围，否则它将是未定义的。