LoginController.php

/**
 * オレが考えたSocialiteのサンプルコード(いまのところ)
 */

// Social Login
Route::prefix('login/{provider}')->where(['provider' => '(facebook|twitter|github|line)'])->group(function () {
    Route::get('/', [App\Http\Controllers\Auth\LoginController::class, 'redirectToProvider'])->name('login.redirect');
    Route::get('/callback', [App\Http\Controllers\Auth\LoginController::class, 'handleProviderCallback'])->name('login.callback');
});

/////

namespace App\Http\Controllers\Auth;

use App\Http\Controllers\Controller;
use App\Models\User;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Hash;
use Illuminate\Support\Str;
use Laravel\Socialite\Facades\Socialite;

class LoginController extends Controller
{
    /**
     * redirectToProvider
     */
    public function redirectToProvider(Request $request)
    {
        $provider = $request->provider;
        return Socialite::driver($provider)->redirect();
    }

    /**
     * handleProviderCallback
     */
    public function handleProviderCallback(string $provider)
    {
        try {
            $providerUser = Socialite::with($provider)->user();
        } catch(\Laravel\Socialite\Two\InvalidStateException $e) {
            // callbackの間が空いたらなる？
            \Log::warning(get_class($e));
            return redirect('/login')->withErrors('ログインできませんでした');
        } catch(\GuzzleHttp\Exception\ClientException $e) {
            // 二重callback
            \Log::warning(get_class($e));
            return redirect('/login')->withErrors('ログインできませんでした');
        } catch(\Exception $e) {
            \Log::error(get_class($e));
            return redirect('/login')->withErrors(['ログインできませんでした', get_class($e)]);
        }

        $user = $this->firstOrCreateUser($providerUser, $provider);
        \Auth::login($user, true);

        return redirect('/dashboard');
    }


    /**
     *  firstOrCreateUser
     *
     *  @param \Laravel\Socialite\Contracts\User $providerUser
     *  @param string $provider
     *  @return \App\Models\User
     */
    private function firstOrCreateUser(\Laravel\Socialite\Contracts\User $providerUser, string $provider): User
    {
        $socialAccount = \App\Models\SocialAccount::where([
            'provider' => $provider,
            'provider_user_id' => $providerUser->getId(),
        ])
            ->first();
        if ($socialAccount) {
            return $socialAccount->user;
        }

        // userと取得したemailが一致したらアカウント連携する
        $email = $providerUser->getEmail();
        $user = User::where('email', $email)->first();
        if ($email && $user) {
            $user->SocialAccount()->create([
                'provider' => $provider,
                'provider_user_id' => $providerUser->getId(),
            ]);
            return $user;
        }

        // ユーザー作成
        $user = User::create([
            'email' => $email,
            'name' => $providerUser->getNickname() ?: $providerUser->getName(),
        ]);
        $user->SocialAccount()->create([
            'provider' => $provider,
            'provider_user_id' => $providerUser->getId(),
        ]);
        return $user;
    }
}