Firebase - permission denied when fetching users

问题

I'm trying to fetch users from a Firebase database with this code but I get this error

cancel error Error Domain=com.firebase Code=1 "Permission Denied" UserInfo={NSLocalizedDescription=Permission Denied}

How should my rules be set up?

Here's the code:

FIRDatabase.database().reference().child("users").observe(.childAdded, with: { (snapshot) in

        print("snapshot \(snapshot)")
        //all users right here n shyt
        if let dictionary = snapshot.value as? [String: AnyObject] {
            let user = User()

            //class properties have to match up with firebase dictionary names
            user.setValuesForKeys(dictionary)
            self.users.append(user)


            DispatchQueue.main.async {
                self.messageTable.reloadData()
            }
        }
            print(snapshot)

        }, withCancel: { (error) in
            print("cancel error \(error)")
    })

This is my rules in Firebase:

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

回答1:

Given your current Security rules you are only giving permission to your current user to access only its own node.

If thats the dynamic you want to go by try making another parent node which contains the details that you would wanna share with other users.

users:{
 userID1 : {../*PERSONAL DETAILS*/},
 userID2 : {../*PERSONAL DETAILS*/},
 userID3 : {../*PERSONAL DETAILS*/},
 userID4 : {../*PERSONAL DETAILS*/},
 userID5 : {../*PERSONAL DETAILS*/},
 ....
  },
USERS_INFO: {
  userID1 : {../*Details to share*/},
  userID2 : {../*Details to share*/},
  userID3 : {../*Details to share*/},
  userID4 : {../*Details to share*/},
  userID5 : {../*Details to share*/},
  ....
  }

And update your security rules to:-

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

Query like :-

 FIRDatabase.database().reference().child("USERS_INFO").observe(.childAdded, with: { (snapshot) in

来源：https://stackoverflow.com/questions/40291114/firebase-permission-denied-when-fetching-users