Laravel _如何将查询注入Auth :: user（）

Question

I'm making a blog with laravel. When I look into user authentication, I have a few issues here. I have 2 tables, one is users: id, name, ... the other is role: user_id, privilege .. I need to check whether a user is admin or not, I will need a function like isAdmin() or a $isAdmin attribute. This is my function placed in the app/providers/AuthServiceProvider.php:

private static $isAdmin;

public static function isAdmin() {
    if (isset(self::$isAdmin)) {
        return self::$isAdmin;
    }
    $user_privilege = DB::table('role')
        ->select('privilege')
        ->where([
            ['privilege', '=', 'admin'],
            ['user_id', '=', Auth::user()->id],
        ])
        ->get()
        ->first();
    self::$isAdmin = isset($user_privilege->privilege);
    return self::$isAdmin;
}

This code works fine, but this will require two queries to the database to check the user's admin rights. So I wanted to find a way to inject a query into Auth :: user () so that only one query would retrieve all the stuff I wanted. I'm a beginner with laravel. Can you help me?

Answer 1

I assume that user can have only one role. You can create isAdmin() method in the User model:

public function isAdmin()
{
    return auth()->user()->role->privilege === 'admin';
}

Define the relationship if you didn't do that yet:

public function role()
{
    return $this->hasOne(Role::class);
}

Then use it with auth()->user()->isAdmin().

If a user can have many roles:

public function isAdmin()
{
    auth()->user()->loadMissing('roles');
    return auth()->user()->roles->contains('admin');
}

And the relationship:

public function roles()
{
    return $this->hasMany(Role::class);
}