Laravelのソフトデリートとデータリストア：論理削除を安全に運用する実装パターン

// 既存テーブルへ追加するマイグレーション例
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

return new class extends Migration {
    public function up(): void
    {
        Schema::table('posts', function (Blueprint $table) {
            $table->softDeletes(); // deleted_at を追加
        });
    }

    public function down(): void
    {
        Schema::table('posts', function (Blueprint $table) {
            $table->dropSoftDeletes();
        });
    }
};

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\SoftDeletes;

class Post extends Model
{
    use SoftDeletes;

    protected $fillable = ['title', 'body'];
}

$post = Post::findOrFail($id);

// 論理削除
$post->delete();

// 復元（削除済みも対象に含める）
Post::withTrashed()->findOrFail($id)->restore();

// 物理削除（復元不可）
Post::withTrashed()->findOrFail($id)->forceDelete();

// 生存データのみ（デフォルト）
$posts = Post::query()->latest()->get();

// 生存 + 削除済み
$all = Post::withTrashed()->latest()->get();

// 削除済みのみ（ゴミ箱一覧）
$trash = Post::onlyTrashed()->latest('deleted_at')->get();

// routes/web.php など（例）
use App\Http\Controllers\PostTrashController;

Route::get('/posts/trash', [PostTrashController::class, 'index']);
Route::post('/posts/{post}/restore', [PostTrashController::class, 'restore']);


// app/Http/Controllers/PostTrashController.php（例）
namespace App\Http\Controllers;

use App\Models\Post;
use Illuminate\Http\RedirectResponse;
use Illuminate\View\View;

class PostTrashController extends Controller
{
    public function index(): View
    {
        $trash = Post::onlyTrashed()->latest('deleted_at')->paginate(20);
        return view('posts.trash', compact('trash'));
    }

    public function restore(int $post): RedirectResponse
    {
        $target = Post::onlyTrashed()->findOrFail($post);
        $target->restore();

        return redirect()->back()->with('status', '復元しました');
    }
}

// 例：Post と Comment がある前提
// app/Models/Post.php
public function comments()
{
    return $this->hasMany(Comment::class);
}

// 削除時に子も削除（イベント/オブザーバ等で呼ぶ想定）
public function softDeleteWithChildren(): void
{
    $this->comments()->delete();
    $this->delete();
}

// 復元時に子も復元
public function restoreWithChildren(): void
{
    $this->restore();
    $this->comments()->withTrashed()->restore();
}

// 例：90日より古い削除済みを物理削除
use App\Models\Post;
use Illuminate\Support\Carbon;

$threshold = Carbon::now()->subDays(90);

Post::onlyTrashed()
    ->where('deleted_at', '<', $threshold)
    ->chunkById(1000, function ($posts) {
        foreach ($posts as $post) {
            $post->forceDelete();
        }
    });