angular – firebase.auth().currentUser为null

我正在尝试在Angular 4应用程序中检索当前登录的firebase用户的UID.但是,如果我将’firebase.auth().currentUser’记录到控制台,我会得到一个’null’.因此’firebase.auth().currentUser.uid’给出’无法读取属性’uid’of null’错误.

根据这篇文章https://firebase.google.com/docs/auth/web/manage-users,这意味着我目前还没有登录.虽然,我是,因为我可以从我的数据库中读取数据(我的规则不允许未经身份验证的用户),并且登录方法没有给出任何错误.

我还可以看到具有uid 1的用户登录了firebase控制台(… / u / 1 / project / my-project / authentication / users)

我的数据库规则：

{
  "rules": {
    "users": {
      "$uid": {
        ".write": "$uid === auth.uid",".read": "$uid === auth.uid"
      }
    }
   }
}

注意：我没有使用任何Firebase登录方法.我正在使用我的php后端来验证用户并为firebase生成自定义令牌,完全如下所述：https://firebase.google.com/docs/auth/admin/create-custom-tokens.

Angular 4登录代码：

constructor(private afAuth: AngularFireAuth) {
    this.login();
}

login() {
    console.log('We are logging in on Firebase :)');
    firebase.auth().signInWithCustomToken(localStorage.getItem('firebase_token')).catch(function (error) {
        console.log(error.message);
        console.log('You are not logged in!');
    });
    this.user = firebase.auth().currentUser;
    console.log(firebase.auth().currentUser);
    console.log(firebase.auth().currentUser.uid);
}

控制台输出：

chat.service.ts:59 We are logging in on Firebase :)
chat.service.ts:65 null
ChatComponent_Host.html:1 ERROR TypeError: Cannot read property 'uid' of null
    at ChatService.Array.concat.ChatService.login (chat.service.ts:66)
    at new ChatService (chat.service.ts:23)
    at _createClass (core.es5.js:9572)
    at _createProviderInstance$1 (core.es5.js:9544)
    at resolveNgModuleDep (core.es5.js:9529)
    at NgModuleRef_.get (core.es5.js:10615)
    at resolveDep (core.es5.js:11118)
    at createClass (core.es5.js:10971)
    at createDirectiveInstance (core.es5.js:10802)
    at createViewNodes (core.es5.js:12230)
    at createRootView (core.es5.js:12125)
    at callWithDebugContext (core.es5.js:13506)
    at Object.debugCreateRootView [as createRootView] (core.es5.js:12823)
    at ComponentFactory_.create (core.es5.js:9916)
    at ComponentFactoryBoundToModule.create (core.es5.js:3333)

constructor(private afAuth: AngularFireAuth) {
    this.login();
}

login() {
    console.log('We are logging in on Firebase :)');
    firebase.auth().signInWithCustomToken(localStorage.getItem('firebase_token'))
    .then(success=>{
    this.user = firebase.auth().currentUser;
    console.log(firebase.auth().currentUser);
    console.log(firebase.auth().currentUser.uid);
    })
   .catch(function (error) {
        console.log(error.message);
        console.log('You are not logged in!');
    });

}