身份验证后无法从 Firebase 读取数据

Question

大家好，我是 Firebase 的新手，我正在尝试开发一个简单的聊天应用程序。到目前为止，我已经按照 Firebase 文档中的步骤完成了身份验证。

这是我的登录方式

loginUser: function(){
        console.log("Login button");
        var self = this;
        ref.authWithOAuthPopup("github", function(error, authData) {
            if (error) { console.log("Login Failed!", error);} 
            else {
                console.log(authData);
                ref.child("users").child(authData.uid).set({
                    auth : authData.auth,
                    provider : authData.provider,
                    name : authData.github.displayName,
                    imgUrl : authData.github.profileImageURL,
                    token: authData.token
                });
                self.user.name = authData.github.displayName;
                self.user.imgUrl = authData.github.profileImageURL;
                self.user.provider = authData.provider;
                setTimeout(function(){ self.authenticated = true; }, 2000);
                this.getContacts();
            }
        },{ 
            remember : "sessionOnly", 
            scope: "user"
        });

    }

这是 getContacts 方法（我尝试控制快照但一无所获）

    getContacts: function(){
        console.log('GET CONTACTS');
        var self = this;
        //retrieving all the user, but for somehow this request doesn't execute
        ref.child('users').once('value',function(snapshot){
            var contacts = snapshot.val();
            console.log(contacts);
            for(var contact  in contacts){
             self.contacts.push({
                id: contact,
                name: contacts[contact].name,
                imgUrl: contacts[contact].imgUrl,
                provider: contacts[contact].provider
             });
            }
        });
    }

这些是安全规则

{
  "rules": {
    "users": {
      "$uid": {
        // grants write access to the owner of this user account whose uid must exactly match the key ($uid)
         ".write": "auth !== null && auth.uid === $uid",
         // grants read access to any user who is logged in with GitHub
         ".read": "auth !== null && auth.provider === 'github'"
       }
     }
 }

不得不说我用的是 Vuejs

Answer 1

您正在授予特定用户访问权限：/users/$uid。但是为了能够运行对 Firebase 中的节点进行查询，您必须具有对该节点的读取权限。因此 Firebase 拒绝了您的查询，因为您无权访问 /users。文档在 "rules are not filters". Many people run into this problem, since this is a very common approach in relational databases. The fact that rules are not filters and that permissions cascade down 部分对此进行了介绍，这是 Firebase 安全模型的两个最常见的陷阱。

在这种情况下，您可能希望授予所有用户访问整个 /users 节点的权限，因此您只需将读取权限上移一级：

{
  "rules": {
   // grants read access to any user who is logged in with GitHub
   ".read": "auth !== null && auth.provider === 'github'"
    "users": {
      "$uid": {
        // grants write access to the owner of this user account whose uid must exactly match the key ($uid)
         ".write": "auth !== null && auth.uid === $uid",
       }
     }
 }

有了这个每个 github-authenticated 用户，都可以读取所有用户，因此查询不会被拒绝。

在其他情况下，您可能必须以不同的方式对数据进行建模才能使用所需的安全约束。

身份验证后无法从 Firebase 读取数据

Can't read data from Firebase after authentication

javascript

firebase

firebase-security

firebase-authentication