firestore security rule request.auth.uid is not working - firebase

Question

Firestore security rules do not work.
Help me.
Document data of users/userid could not be read.
----------Security Rule------------
service cloud.firestore {
match /databases/{database}/documents {
match /users/{userId=**} {
// Missing or insufficient permissions.
allow read, write: if request.auth.uid == userId
// this is work.
//allow read, write: if request.auth != null
}
}
}
--------------main.js--------------------
import Vue from 'vue'
import Quasar from 'quasar'
import firebase from 'firebase'
import 'firebase/firestore'
Vue.config.productionTip = false
Vue.use(Quasar)
let app;
firebase.initializeApp({
apiKey: "",
authDomain: "",
databaseURL: "",
projectId: "",
storageBucket: "",
messagingSenderId: ""
})
firebase.auth().onAuthStateChanged(user=> {
if (user) {
let ref = firebase.firestore().collection('users').doc(user.uid)
ref.get().then(snapshot=>{
// Error !! : Missing or insufficient permissions.
}
}
if(!app){
Quasar.start(() => {
app = new Vue({
el: '#q-app',
render: h => h(require('./App').default)
})
})
}
})
firebase ^4.8.0
vue ^2.5.0
Apparently, require.auth.uid does not seem to work properly.
Where is there a mistake in me?

Answer 1

I was able to solve it self
match /users/{user} {
   allow read, write: if request.auth.uid == user
   match / {docs = **} {
      allow read, write: if request.auth.uid == user
   }
 }

Answer 2

I followed the example I found here (under the User tab) and it's working great:
// Grants a user access to a node matching their user ID
service firebase.storage {
match /databases/{database}/documents {
match /users/{userId}/{documents=**} {
allow read, write: if isOwner(userId);
}
}
function isOwner(userId) {
return request.auth.uid == userId;
}
}

Answer 3

match /users/{userId}/{documents=**} {
// return request.auth.uid == userId
function isAuth(){
return request.auth != null
}
allow read,write:if (isAuth() && request.auth.uid == userId)
}
this solution work for this error.