Javascript 在设置firebase之后，我得到以下错误：客户端没有'；我没有访问所需数据的权限

我只想将firbase安装为数据库，但不断出现以下错误：

ERROR Error: permission_denied at /courses: Client doesn't have permission to access the desired data.
    at errorForServerCode (index.cjs.js:647)
    at onComplete (index.cjs.js:9114)
    at Object.onComplete (index.cjs.js:12681)
    at index.cjs.js:11797
    at PersistentConnection.push../node_modules/@firebase/database/dist/index.cjs.js.PersistentConnection.onDataMessage_ (index.cjs.js:12052)
    at Connection.push../node_modules/@firebase/database/dist/index.cjs.js.Connection.onDataMessage_ (index.cjs.js:11337)
    at Connection.push../node_modules/@firebase/database/dist/index.cjs.js.Connection.onPrimaryMessageReceived_ (index.cjs.js:11331)
    at WebSocketConnection.onMessage (index.cjs.js:11232)
    at WebSocketConnection.push../node_modules/@firebase/database/dist/index.cjs.js.WebSocketConnection.appendFrame_ (index.cjs.js:10837)
    at WebSocketConnection.push../node_modules/@firebase/database/dist/index.cjs.js.WebSocketConnection.handleIncomingFrame (index.cjs.js:10887)

app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AngularFireModule } from 'angularfire2';
import { AngularFireDatabaseModule } from 'angularfire2/database';
import { environment } from '../environments/environment';

  imports: [
    BrowserModule,
    AngularFireModule.initializeApp(environment.firebase),
    AngularFireDatabaseModule,
  ]

app.component.ts

export class AppComponent implements OnInit {
  courses: Observable<any>;

  constructor(private _db: AngularFireDatabase) {}

  ngOnInit() {
    this.courses = this._db.list('/courses').valueChanges();
  }
}

没用

npm install firebase-tools --save
firebase login
firebase init

也没用

文件database.rules.json

{
  "rules": {
    ".read": "true",
    ".write": "true"
  }
}

console.firebase.google.com网站上的“规则”选项卡

service cloud.firestore {
  match /databases/{database}/documents {
    match /{document=**} {
      allow read, write: if true;
    }
  }
}

---

请告诉我如何在Angular 6中正确安装firebase，在site console.firebase.google.com的数据库选项卡中，我选择了实时数据库，而不是默认的Cloud Firestore（beta）。

您已经为Cloud Firestore数据库设置了安全规则。但是您的代码正在尝试从Firebase实时数据库中读取。这两个数据库完全分开，并使用不同的安全规则来控制访问

要允许对实时数据库中的

/courses

节点进行读/写访问，请转到并使用：

---

通常，在控制台中编写“Firebase deploy”命令后会出现此错误。如果这是某种培训项目，那么只需手动将安全规则更改为“read:true”和“write:true”

在Firebase auth中，有一种很好的方法允许用户在实际登录之前匿名登录

首先在firebase脚本之后包括auth模块的脚本，如下所示：

     <!-- The core Firebase JS SDK is always required and must be listed first -->
  <script src="https://www.gstatic.com/firebasejs/7.19.1/firebase-app.js"></script>

  <!-- TODO: Add SDKs for Firebase products that you want to use
       https://firebase.google.com/docs/web/setup#available-libraries -->

  <script src="https://www.gstatic.com/firebasejs/7.19.1/firebase-auth.js"></script>
  <script src="https://www.gstatic.com/firebasejs/7.19.1/firebase-database.js"></script>

{
  "rules": {
    "courses": {
      ".read": true,
      ".write": true
    }
  }
}

     <!-- The core Firebase JS SDK is always required and must be listed first -->
  <script src="https://www.gstatic.com/firebasejs/7.19.1/firebase-app.js"></script>

  <!-- TODO: Add SDKs for Firebase products that you want to use
       https://firebase.google.com/docs/web/setup#available-libraries -->

  <script src="https://www.gstatic.com/firebasejs/7.19.1/firebase-auth.js"></script>
  <script src="https://www.gstatic.com/firebasejs/7.19.1/firebase-database.js"></script>

firebase.auth().signInAnonymously();