"Attempt to read property \"id\" on null", Create access token error with laravel passport, laravel 9, php 8.2.2 - laravel-9

Question

devs,
so I have been struggling with this problem for about 10 hours now, and I can't seem to find a solution online, worst is that I don't even know why it happens.
I am working on a project which uses PHP LARAVEL as the backend and I started writing the API for the flutter frontend to consume then I ran into this error while trying to test the API endpoint for registering and logging in.
The problem is the process fails with this error when I try to generate or create a token for the registered user or logged-in user.
Here a snapshot of my register function
public function store(Request $request)
{
$validated = Validator::make($request->all(),[
"email" => "required|email",
"password" => 'required',
"first_name"=> "required",
"last_name" => "required",
"phone_number" => 'required',
]);
if ($validated->fails()) {
return response()->json(['errors' => "Invalide credentials"], 403);
}
$user = User::create(
// [
// 'first_name' => $request->first_name,
// 'last_name'=> $request->last_name,
// 'email' => $request->email,
// 'password' => bcrypt($request->password),
// 'phone_number' => $request->phone_number,
// ]
$request->toArray()
);
Auth::guard('api')->check($user);
// $newUser = User::find($user->id);
$token = $user->createToken('authToken')->accessToken;
// return $token;
return response(['token' => $token, 'first_name'=>$user->first_name, 'email'=>$user->email ], 200);
}
The login and register functions all look the same at this point.
Error-causing code is :
$token = $user->createToken('authToken')->accessToken;
Please I am open to your suggestions, thanks.

Answer 1

I finally found a solution for this error and I believe it will help anyone out there with a similar problem.
The problem originates from the fact that your application is unable to asign a unique id to your client, remember your website or mobile app is a client to the backend with also(your mobile app or website) might have other users, so laravel passport will need to identify it with a unique id, below are some of the steps i used to fix this error.
First it originates because during the passport installation, i forgot to install
Blockquote
--uuids
If you have a similar error, follow the steps below to fix:
NOTE: You must have laravel passport installed already, if not, them follow the complete installtion guide Here
Step 1:
Install passport uuids
php artisan passport:install --uuids
Your result will look something like
After creating, the uuid for your application, you will have to include it in your .env file as such:
PASSPORT_PERSONAL_ACCESS_CLIENT_ID=986eb40c-0458-4b6e-bead-ea2fc4987033
PASSPORT_PERSONAL_ACCESS_CLIENT_SECRET=VXLdTpqWK9i3CBqFwZgje5fuerQ5Uf2lvwXJqBoP
And there you go, you can now try to do what you couldn't do before.