当我使用googleauth注册时，我想在实际字段中添加一个额外的字段（性别）：name、email和password。请给我看看。

public function callback()
{
    try {

        $googleUser = Socialite::driver('google')->user();  
        $existUser = User::where('email',$googleUser->email)->first();

        if($existUser) {
            Auth::loginUsingId($existUser->id);
        }
        else {
            $user = new User;
            $user->name = $googleUser->name;
            $user->email = $googleUser->email;
            $user->password = md5(rand(1,10000));
            $user->save();
            Auth::loginUsingId($user->id);
        }
        return redirect()->to('/home');
    } 
    catch (Exception $e) {
        return 'error';
    }
}