feat: fix idempotency cache

.env.example

@@ -1,6 +1,6 @@
 APP_NAME=Laravel
 APP_ENV=local
-APP_KEY=
+APP_KEY=base64:MR10CFjbrEDkYi2FLwW0tNNHGHleWthQlxD5LLKdFnQ=
 APP_DEBUG=true
 APP_URL=http://localhost
 
@@ -20,12 +20,12 @@ LOG_STACK=single
 LOG_DEPRECATIONS_CHANNEL=null
 LOG_LEVEL=debug
 
-DB_CONNECTION=sqlite
-# DB_HOST=127.0.0.1
-# DB_PORT=3306
-# DB_DATABASE=laravel
-# DB_USERNAME=root
-# DB_PASSWORD=
+DB_CONNECTION=mysql
+DB_HOST=mysql
+DB_PORT=3306
+DB_DATABASE=slots
+DB_USERNAME=slots
+DB_PASSWORD=slots
 
 SESSION_DRIVER=database
 SESSION_LIFETIME=120
@@ -37,13 +37,13 @@ BROADCAST_CONNECTION=log
 FILESYSTEM_DISK=local
 QUEUE_CONNECTION=database
 
-CACHE_STORE=database
+CACHE_STORE=redis
 # CACHE_PREFIX=
 
 MEMCACHED_HOST=127.0.0.1
 
 REDIS_CLIENT=phpredis
-REDIS_HOST=127.0.0.1
+REDIS_HOST=redis
 REDIS_PASSWORD=null
 REDIS_PORT=6379
 

README.md

@@ -1,59 +1,48 @@
-<p align="center"><a href="https://laravel.com" target="_blank"><img src="https://raw.githubusercontent.com/laravel/art/master/logo-lockup/5%20SVG/2%20CMYK/1%20Full%20Color/laravel-logolockup-cmyk-red.svg" width="400" alt="Laravel Logo"></a></p>
+# Start
+```bash
+git clone ...
+docker compose up -d
+```
 
-<p align="center">
-<a href="https://github.com/laravel/framework/actions"><img src="https://github.com/laravel/framework/workflows/tests/badge.svg" alt="Build Status"></a>
-<a href="https://packagist.org/packages/laravel/framework"><img src="https://img.shields.io/packagist/dt/laravel/framework" alt="Total Downloads"></a>
-<a href="https://packagist.org/packages/laravel/framework"><img src="https://img.shields.io/packagist/v/laravel/framework" alt="Latest Stable Version"></a>
-<a href="https://packagist.org/packages/laravel/framework"><img src="https://img.shields.io/packagist/l/laravel/framework" alt="License"></a>
-</p>
+# Доступность
+```bash
+curl -s "http://localhost:8080/api/slots/availability"
+```
 
-## About Laravel
+# Создать hold
 
-Laravel is a web application framework with expressive, elegant syntax. We believe development must be an enjoyable and creative experience to be truly fulfilling. Laravel takes the pain out of development by easing common tasks used in many web projects, such as:
+```bash
+curl -s -X POST "http://localhost:8080/api/slots/1/hold" \
+    -H "X-Idempotency-Key: 3f36b498-4144-43d3-9853-b22379b520ff"
+```
 
-- [Simple, fast routing engine](https://laravel.com/docs/routing).
-- [Powerful dependency injection container](https://laravel.com/docs/container).
-- Multiple back-ends for [session](https://laravel.com/docs/session) and [cache](https://laravel.com/docs/cache) storage.
-- Expressive, intuitive [database ORM](https://laravel.com/docs/eloquent).
-- Database agnostic [schema migrations](https://laravel.com/docs/migrations).
-- [Robust background job processing](https://laravel.com/docs/queues).
-- [Real-time event broadcasting](https://laravel.com/docs/broadcasting).
+# Подтвердить
+```bash
+curl -s -X POST "http://localhost:8080/api/holds/1/confirm"
+```
 
-Laravel is accessible, powerful, and provides tools required for large, robust applications.
+# Отменить
+```bash
+curl -s -X DELETE "http://localhost:8080/api/holds/1"
+```
 
-## Learning Laravel
-
-Laravel has the most extensive and thorough [documentation](https://laravel.com/docs) and video tutorial library of all modern web application frameworks, making it a breeze to get started with the framework. You can also check out [Laravel Learn](https://laravel.com/learn), where you will be guided through building a modern Laravel application.
-
-If you don't feel like reading, [Laracasts](https://laracasts.com) can help. Laracasts contains thousands of video tutorials on a range of topics including Laravel, modern PHP, unit testing, and JavaScript. Boost your skills by digging into our comprehensive video library.
-
-## Laravel Sponsors
-
-We would like to extend our thanks to the following sponsors for funding Laravel development. If you are interested in becoming a sponsor, please visit the [Laravel Partners program](https://partners.laravel.com).
-
-### Premium Partners
-
-- **[Vehikl](https://vehikl.com)**
-- **[Tighten Co.](https://tighten.co)**
-- **[Kirschbaum Development Group](https://kirschbaumdevelopment.com)**
-- **[64 Robots](https://64robots.com)**
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-- **[Redberry](https://redberry.international/laravel-development)**
-- **[Active Logic](https://activelogic.com)**
-
-## Contributing
-
-Thank you for considering contributing to the Laravel framework! The contribution guide can be found in the [Laravel documentation](https://laravel.com/docs/contributions).
-
-## Code of Conduct
-
-In order to ensure that the Laravel community is welcoming to all, please review and abide by the [Code of Conduct](https://laravel.com/docs/contributions#code-of-conduct).
-
-## Security Vulnerabilities
-
-If you discover a security vulnerability within Laravel, please send an e-mail to Taylor Otwell via [taylor@laravel.com](mailto:taylor@laravel.com). All security vulnerabilities will be promptly addressed.
-
-## License
-
-The Laravel framework is open-sourced software licensed under the [MIT license](https://opensource.org/licenses/MIT).
+# Oversell
+```bash
+curl -s -X POST "http://localhost:8080/api/slots/2/hold" \
+    -H "X-Idempotency-Key: 20ff64a3-43d6-4ddb-874e-441d0a87570e"
+    
+curl -s -X POST "http://localhost:8080/api/slots/2/hold" \
+    -H "X-Idempotency-Key: d7db5b73-1ea5-4156-99b6-dbace1b483a9"
+    
+curl -s -X POST "http://localhost:8080/api/slots/2/hold" \
+    -H "X-Idempotency-Key: ddd6174c-0fda-4765-8413-12dd3cda9692"
+    
+curl -s -X POST "http://localhost:8080/api/slots/2/hold" \
+    -H "X-Idempotency-Key: 7af943b4-dfcf-4d5e-99c0-fa06fc9b2a6a"
+    
+curl -s -X POST "http://localhost:8080/api/slots/2/hold" \
+    -H "X-Idempotency-Key: fcb4b745-e928-4af3-bb35-c307cc5a574e"
+    
+curl -s -X POST "http://localhost:8080/api/slots/2/hold" \
+    -H "X-Idempotency-Key: 38ae0adb-7f23-40c0-9ac1-069a15d89a98"
+```

app/Exceptions/HoldNotAvailableException.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace App\Exceptions;
+
+use RuntimeException;
+
+class HoldNotAvailableException extends RuntimeException
+{
+}

app/Exceptions/SlotCapacityExceededException.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace App\Exceptions;
+
+use RuntimeException;
+
+class SlotCapacityExceededException extends RuntimeException
+{
+}

app/Http/Controllers/AvailabilityController.php

@@ -2,9 +2,18 @@
 
 namespace App\Http\Controllers;
 
-use Illuminate\Http\Request;
+use App\Services\SlotService;
+use Illuminate\Http\JsonResponse;
 
 class AvailabilityController extends Controller
 {
-    //
+    public function __construct(
+        private readonly SlotService $slotService,
+    ) {
+    }
+
+    public function index(): JsonResponse
+    {
+        return response()->json($this->slotService->getAvailability());
+    }
 }

app/Http/Controllers/HoldController.php

@@ -2,9 +2,63 @@
 
 namespace App\Http\Controllers;
 
-use Illuminate\Http\Request;
+use App\Exceptions\HoldNotAvailableException;
+use App\Exceptions\SlotCapacityExceededException;
+use App\Models\Hold;
+use App\Models\Slot;
+use App\Services\SlotService;
+use Illuminate\Http\JsonResponse;
+use Symfony\Component\HttpFoundation\Response;
 
 class HoldController extends Controller
 {
-    //
+    public function __construct(
+        private readonly SlotService $slotService,
+    ) {
+    }
+
+    public function store(Slot $slot): JsonResponse
+    {
+        $idempotencyKey = request()->header('X-Idempotency-Key');
+
+        try {
+            $hold = $this->slotService->createHold($slot, $idempotencyKey);
+        } catch (SlotCapacityExceededException $exception) {
+            return response()->json([
+                'message' => $exception->getMessage()
+            ], Response::HTTP_CONFLICT);
+        }
+
+        return response()->json($this->holdPayload($hold), Response::HTTP_CREATED);
+    }
+
+    public function confirm(Hold $hold): JsonResponse
+    {
+        try {
+            $hold = $this->slotService->confirmHold($hold);
+        } catch (HoldNotAvailableException $exception) {
+            return response()->json([
+                'message' => $exception->getMessage()
+            ], Response::HTTP_CONFLICT);
+        }
+
+        return response()->json($this->holdPayload($hold));
+    }
+
+    public function destroy(Hold $hold): JsonResponse
+    {
+        $hold = $this->slotService->cancelHold($hold);
+
+        return response()->json($this->holdPayload($hold));
+    }
+
+    private function holdPayload(Hold $hold): array
+    {
+        return [
+            'id' => $hold->id,
+            'slot_id' => $hold->slot_id,
+            'status' => $hold->status,
+            'expires_at' => $hold->expires_at->toIso8601String(),
+        ];
+    }
 }

app/Http/Middleware/IdempotencyMiddleware.php

@@ -0,0 +1,110 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\Cache;
+use Illuminate\Support\Str;
+use Symfony\Component\HttpFoundation\Response;
+
+class IdempotencyMiddleware
+{
+    public function handle(Request $request, Closure $next): Response
+    {
+        $idempotencyKey = $request->header('X-Idempotency-Key');
+
+        if (! is_string($idempotencyKey) || ! Str::isUuid($idempotencyKey)) {
+            return response()->json([
+                'message' => 'X-Idempotency-Key MUST be a valid UUID.',
+            ], Response::HTTP_BAD_REQUEST);
+        }
+
+        $cacheKey = $this->cacheKey($request, $idempotencyKey);
+        $lockKey = $this->lockKey($request, $idempotencyKey);
+
+        // Проверяем чтобы не выполнять код
+        $cached = Cache::get($cacheKey);
+        if (is_array($cached)) {
+            return $this->replayResponse($cached);
+        }
+
+        $lock = Cache::lock($lockKey, config('slots.idempotency_lock_seconds'));
+        if (! $lock->get()) {
+            return $this->waitForCachedResponse($cacheKey) ?? $this->inProgressResponse();
+        }
+
+        $response = $next($request);
+
+        try {
+            $cached = Cache::get($cacheKey);
+            if (is_array($cached)) {
+                return $this->replayResponse($cached);
+            }
+
+            if ($response instanceof JsonResponse) {
+                Cache::put($cacheKey, [
+                    'status' => $response->getStatusCode(),
+                    'body' => $response->getData(true),
+                ], config('slots.idempotency_cache_ttl_seconds'));
+            }
+
+            return $response;
+        } finally {
+            $lock->release();
+        }
+    }
+
+    private function waitForCachedResponse(string $cacheKey): ?JsonResponse
+    {
+        $deadline = microtime(true) + config('slots.idempotency_wait_seconds');
+
+        while (microtime(true) < $deadline) {
+            $cached = Cache::get($cacheKey);
+            if (is_array($cached) && isset($cached['body'], $cached['status'])) {
+                return $this->replayResponse($cached);
+            }
+
+            usleep(100_000);
+        }
+
+        return null;
+    }
+
+    private function inProgressResponse(): ?JsonResponse
+    {
+        return response()->json([
+            'message' => 'Conflict. Retry with same idempotency key',
+        ], Response::HTTP_CONFLICT)
+            ->header('X-Retry-After', 1);
+    }
+
+    /**
+     * @param array{status: int, body: string} $data
+     */
+    private function replayResponse(array $data): JsonResponse
+    {
+        return response()->json($data['body'], (int) $data['status']);
+    }
+
+    private function cacheKey(Request $request, string $idempotencyKey): string
+    {
+        return sprintf(
+            'idempotency:response:%s:%s:%s',
+            strtoupper($request->method()),
+            $request->path(),
+            $idempotencyKey
+        );
+    }
+
+    private function lockKey(Request $request, string $idempotencyKey): string
+    {
+        return sprintf(
+            'idempotency:lock:%s:%s:%s',
+            strtoupper($request->method()),
+            $request->path(),
+            $idempotencyKey
+        );
+    }
+}

app/Services/SlotService.php

@@ -2,7 +2,153 @@
 
 namespace App\Services;
 
+use App\Enums\HoldStatus;
+use App\Exceptions\HoldNotAvailableException;
+use App\Exceptions\SlotCapacityExceededException;
+use App\Models\Hold;
+use App\Models\Slot;
+use Illuminate\Database\UniqueConstraintViolationException;
+use Illuminate\Support\Facades\Cache;
+use Illuminate\Support\Facades\DB;
+
 class SlotService
 {
+    private const string AVAILABILITY_CACHE_KEY = 'slots:availability';
 
+    /**
+     * @return list<array{slot_id: int, capacity: int, remaining: int}>
+     */
+    public function getAvailability(): array
+    {
+        $fresh = config('slots.availability_cache_fresh_seconds');
+        $ttl = config('slots.availability_cache_ttl_seconds');
+
+        return Cache::flexible(self::AVAILABILITY_CACHE_KEY, [$fresh, $ttl], function (): array {
+            return $this->buildAvailabilityPayload();
+        });
+    }
+
+    private function buildAvailabilityPayload(): array
+    {
+        return Slot::query()
+            ->orderBy('id')
+            ->get()
+            ->map(fn (Slot $slot): array => [
+                'slot_id' => $slot->id,
+                'capacity' => $slot->capacity,
+                'remaining' => $this->availableRemaining($slot),
+            ])
+            ->all();
+    }
+
+    public function createHold(Slot $slot, string $idempotencyKey): Hold
+    {
+        $existing = $this->findHoldByIdempotencyKey($idempotencyKey);
+        if ($existing !== null) {
+            return $existing->load('slot');
+        }
+
+        try {
+            return DB::transaction(function () use ($slot, $idempotencyKey): Hold {
+                $lockedSlot = Slot::query()->lockForUpdate()->findOrFail($slot->id);
+
+                if ($this->availableRemaining($lockedSlot) <= 0) {
+                    throw new SlotCapacityExceededException('Slot capacity is exhausted.');
+                }
+
+                return Hold::query()->create([
+                   'slot_id' => $lockedSlot->id,
+                   'idempotency_key' => $idempotencyKey,
+                   'status' => HoldStatus::Held,
+                   'expires_at' => now()->addMinutes(config('slots.hold_ttl_minutes')),
+                ])->load('slot');
+            });
+        } catch (UniqueConstraintViolationException) {
+            $existing = $this->findHoldByIdempotencyKey($idempotencyKey);
+
+            if ($existing === null) {
+                throw new SlotCapacityExceededException('Slot capacity is exhausted.');
+            }
+
+            return $existing->load('slot');
+        }
+    }
+
+    public function confirmHold(Hold $hold): Hold
+    {
+        return DB::transaction(function () use ($hold) {
+            $lockedHold = Hold::query()->lockForUpdate()->findOrFail($hold->id);
+
+            if ($lockedHold->status === HoldStatus::Confirmed) {
+                return $lockedHold->load('slot');
+            }
+
+            if ($lockedHold->status !== HoldStatus::Held || $lockedHold->isExpired()) {
+                throw new HoldNotAvailableException('Hold cannot be confirmed');
+            }
+
+            $slot = Slot::query()->lockForUpdate()->findOrFail($lockedHold->slot_id);
+
+            if ($slot->remaining < 1) {
+                throw new SlotCapacityExceededException('Slot capacity is exhausted.');
+            }
+
+            $slot->remaining--;
+            $slot->save();
+
+            $lockedHold->status = HoldStatus::Confirmed;
+            $lockedHold->save();
+
+            $this->invalidateAvailabilityCache();
+
+            return $lockedHold->load('slot');
+        });
+    }
+
+    public function cancelHold(Hold $hold): Hold
+    {
+        return DB::transaction(function () use ($hold) {
+           $lockedHold = Hold::query()->lockForUpdate()->findOrFail($hold->id);
+
+           if ($lockedHold->status === HoldStatus::Cancelled) {
+               return $lockedHold->load('slot');
+           }
+
+           if ($lockedHold->status === HoldStatus::Confirmed) {
+               $slot = Slot::query()->lockForUpdate()->findOrFail($lockedHold->slot_id);
+               $slot->remaining = min($slot->capacity, $slot->remaining + 1);
+               $slot->save();
+           }
+
+           $lockedHold->status = HoldStatus::Cancelled;
+           $lockedHold->save();
+
+            $this->invalidateAvailabilityCache();
+
+           return $lockedHold->load('slot');
+        });
+    }
+
+    private function availableRemaining(Slot $slot): int
+    {
+        $activeHolds = Hold::query()
+            ->where('slot_id', $slot->id)
+            ->where('status', HoldStatus::Held)
+            ->where('expires_at', '>', now())
+            ->count();
+
+        return max(0, $slot->remaining - $activeHolds);
+    }
+
+    private function findHoldByIdempotencyKey(string $idempotencyKey): ?Hold
+    {
+        return Hold::query()
+            ->where('idempotency_key', $idempotencyKey)
+            ->first();
+    }
+
+    private function invalidateAvailabilityCache(): void
+    {
+        Cache::forget(self::AVAILABILITY_CACHE_KEY);
+    }
 }

bootstrap/app.php

@@ -1,5 +1,6 @@
 <?php
 
+use App\Http\Middleware\IdempotencyMiddleware;
 use Illuminate\Foundation\Application;
 use Illuminate\Foundation\Configuration\Exceptions;
 use Illuminate\Foundation\Configuration\Middleware;
@@ -7,11 +8,14 @@ use Illuminate\Foundation\Configuration\Middleware;
 return Application::configure(basePath: dirname(__DIR__))
     ->withRouting(
         web: __DIR__.'/../routes/web.php',
+        api: __DIR__.'/../routes/api.php',
         commands: __DIR__.'/../routes/console.php',
         health: '/up',
     )
     ->withMiddleware(function (Middleware $middleware): void {
-        //
+        $middleware->alias([
+            'idempotency' => IdempotencyMiddleware::class
+        ]);
     })
     ->withExceptions(function (Exceptions $exceptions): void {
         //

database/seeders/SlotSeeder.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace Database\Seeders;
+
+use App\Models\Slot;
+use Illuminate\Database\Seeder;
+
+class SlotSeeder extends Seeder
+{
+    public function run(): void
+    {
+        Slot::query()->upsert([
+            ['id' => 1, 'capacity' => 10, 'remaining' => 10],
+            ['id' => 2, 'capacity' => 5, 'remaining' => 5],
+        ], ['id'], ['capacity', 'remaining']);
+    }
+}

docker-compose.yml

@@ -27,13 +27,14 @@ services:
         condition: service_healthy
       redis:
         condition: service_started
-#    command: >
-#      sh -c "
-#        composer install --no-interaction &&
-#        php artisan migrate --force &&
-#        php artisan db:seed --class=SlotSeeder --force &&
-#        php artisan serve --host=0.0.0.0 --port=8000
-#      "
+    command: >
+      sh -c "
+        composer install --no-interaction &&
+        cp .env.example .env
+        php artisan migrate --force &&
+        php artisan db:seed --class=SlotSeeder --force &&
+        php artisan serve --host=0.0.0.0 --port=8000
+      "
 
   mysql:
     image: mysql:8.4

routes/api.php

@@ -0,0 +1,13 @@
+<?php
+
+use App\Http\Controllers\AvailabilityController;
+use App\Http\Controllers\HoldController;
+use Illuminate\Support\Facades\Route;
+
+Route::get('/slots/availability', [AvailabilityController::class, 'index']);
+
+Route::post('/slots/{slot}/hold', [HoldController::class, 'store'])
+    ->middleware('idempotency');
+
+Route::post('/holds/{hold}/confirm', [HoldController::class, 'confirm']);
+Route::delete('/holds/{hold}', [HoldController::class, 'destroy']);