Firebase数据库规则+身份验证无效

I can't seem to get my database rules to work, when they require authentication.

The user is logged in using JavaScript, and then the database is updated via PHP / REST request using firebase-php.

PHP:

$firebase = new \Firebase\FirebaseLib('https://AppNameGoesHere.firebaseio.com/');

$data = array(
   'field1' => $response_array['field1'],
   'field2' => $response_array['field2'],
   'field3' => $response_array['field3']
);

$firebase->set('users/' . $response_array['userID'], $data)

The $response_array is an array from an HTML form. $response_array['userID'] is the Firebase user uid.

These rules work (no auth):

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

These, with auth, don't work:

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

Error:

{ "error" : "Permission denied" }

Any suggestions?

As Frank mentioned in the comments, you must call setToken() in order to authenticate all subsequent database reads/writes. To get that token from the client-side JavaScript and pass it to your PHP endpoint, you should use getIdToken like so:

firebase.auth().currentUser.getIdToken(/* forceRefresh */ true).then(function(idToken) {
  // Send token to your PHP backend via HTTPS
  // ...
}).catch(function(error) {
  // Handle error
});

With that idToken value, it looks like you can pass that along to the firebase-php library's setToken function:

...
$firebase->setToken(idToken)
$firebase->set('users/' . $response_array['userID'], $data)

As long as $response_array['userID'] matches up with the uid of whoever makes that request, you should no longer receive the Permission denied error.