Desarrollo de una API REST para gestión de ofertas flash con Slim Framework y Redis

$redis->set('key', 'value');
$value = $redis->get('key');
echo $value; // Output: value

$redis->set('counter', 1);
$redis->incr('counter');
echo $redis->get('counter'); // Output: 2
$redis->decr('counter');
echo $redis->get('counter'); // Output: 1

$redis->lPush('list', 'value1');
$redis->rPush('list', 'value2');
$list = $redis->lRange('list', 0, -1);
print_r($list); // Output: Array ( [0] => value1 [1] => value2 )

$redis->hSet('hash', 'field1', 'value1');
$redis->hSet('hash', 'field2', 'value2');
$field1 = $redis->hGet('hash', 'field1');
$field2 = $redis->hGet('hash', 'field2');
echo $field1; // Output: value1
echo $field2; // Output: value2

{
    "product_id": "123",
    "discount": "30",
    "stock": "100",
    "expires_at": "1717609200"
}

{
    "user_id": "456"
}

<?php

require dirname(__DIR__) . '/vendor/autoload.php';

use Psr\Http\Message\RequestInterface;
use Psr\Http\Message\ResponseInterface;
use Slim\Factory\AppFactory;

// Crear la aplicación
$app = AppFactory::create();

// Conectar a Redis
$redis = new Redis();
$redis->connect('redis', 6379);

// Configurar el prefijo para las rutas de la API
$prefix = '/api';

// Configurar Slim para procesar datos JSON
$app->addBodyParsingMiddleware();

// Función auxiliar para manejar la respuesta
function createJsonResponse(ResponseInterface $response, array $data): ResponseInterface
{
    // Establecer el tipo de contenido de la respuesta
    $response = $response->withHeader('Content-Type', 'application/json; charset=utf-8');

    // Escribir la respuesta
    $response->getBody()->write(json_encode($data));

    // Devolver la respuesta
    return $response;
}

// Definir las rutas de la aplicación
$app->get("/", function (RequestInterface $request, ResponseInterface $response, array $args) {
    echo file_get_contents('./index.html'); (1)

    return $response;
});

/*
 ****************************************************
 * Aquí se implementarán los endpoints de la API REST
 ****************************************************
 */

// Ejecutar la aplicación
$app->run();

// Endpoint de prueba
$app->get($prefix . '/test', function (RequestInterface $request, ResponseInterface $response) {
    $data = [
        'status' => 200,
        'message' => 'API is working'
    ];

    return createJsonResponse($response, $data);
});

HSET offer:123 product_id 123 discount 30 stock 100 expires_at 1717609200

// Endpoint para crear una nueva oferta
$app->post($prefix . '/offers', function (RequestInterface $request, ResponseInterface $response) use ($redis) {
    $body = $request->getParsedBody();
    $product_id = $body['product_id'];
    $discount = $body['discount'];
    $stock = $body['stock'];
    $expires_in = $body['expires_in'];

    $offer_key = "offer:$product_id";
    $expires_at = time() + $expires_in;

    // Guardar los datos de la oferta en Redis
    $redis->hSet($offer_key, 'product_id', $product_id);
    $redis->hSet($offer_key, 'discount', $discount);
    $redis->hSet($offer_key, 'stock', $stock);
    $redis->hSet($offer_key, 'expires_at', $expires_at);
    $redis->expire($offer_key, $expires_in);

    $data = [
        'status' => 200,
        'message' => 'Offer created successfully',
        'offer' => [
            'product_id' => $product_id,
            'discount' => $discount,
            'stock' => $stock,
            'expires_at' => $expires_at
        ]
    ];

    return createJsonResponse($response, $data);
});

HGETALL offer:123

// Endpoint para obtener detalles de una oferta
$app->get($prefix . '/offers/{product_id}', function (RequestInterface $request, ResponseInterface $response, array $args) use ($redis) {
    $product_id = $args['product_id'];
    $offer_key = "offer:$product_id";

    if (!$redis->exists($offer_key)) {
        $data = [
            'status' => 404,
            'message' => 'Offer not found'
        ];
        return createJsonResponse($response->withStatus(404), $data);
    }

    $offer = $redis->hGetAll($offer_key);
    $time_remaining = $redis->ttl($offer_key);

    $data = [
        'status' => 200,
        'offer' => $offer,
        'time_remaining' => $time_remaining
    ];

    return createJsonResponse($response, $data);
});

WATCH offer:123:stock
stock = HGET offer:123 stock
if stock > 0
    MULTI
    HINCRBY offer:123 stock -1
    LPUSH offer:123:reservations user_456
    EXEC

// Endpoint para reservar un producto en oferta
$app->post($prefix . '/offers/{product_id}/reserve', function (RequestInterface $request, ResponseInterface $response, array $args) use ($redis) {
    $product_id = $args['product_id'];
    $body = $request->getParsedBody();
    $user_id = $body['user_id'];
    $offer_key = "offer:$product_id";

    if (!$redis->exists($offer_key)) {
        $data = [
            'status' => 404,
            'message' => 'Offer not found'
        ];
        return createJsonResponse($response->withStatus(404), $data);
    }

    $redis->watch("$offer_key:stock");
    $stock = $redis->hGet($offer_key, 'stock');

    if ($stock > 0) {
        $redis->multi();
        $redis->hIncrBy($offer_key, 'stock', -1);
        $redis->lPush("$offer_key:reservations", "user_$user_id");
        $result = $redis->exec();

        if ($result) {
            $data = [
                'status' => 200,
                'message' => 'Product reserved successfully',
                'remaining_stock' => $stock - 1
            ];
        } else {
            $data = [
                'status' => 500,
                'message' => 'Failed to reserve product, please try again'
            ];
        }
    } else {
        $data = [
            'status' => 400,
            'message' => 'Out of stock'
        ];
    }

    return createJsonResponse($response, $data);
});

LRANGE offer:123:reservations 0 -1

// Endpoint para obtener la lista de usuarios con reserva en una oferta
$app->get($prefix . '/offers/{product_id}/reservations', function (RequestInterface $request, ResponseInterface $response, array $args) use ($redis) {
    $product_id = $args['product_id'];
    $offer_key = "offer:$product_id:reservations";

    if (!$redis->exists($offer_key)) {
        $data = [
            'status' => 404,
            'message' => 'No reservations found for this offer'
        ];
        return createJsonResponse($response->withStatus(404), $data);
    }

    $reservations = $redis->lRange($offer_key, 0, -1);

    $data = [
        'status' => 200,
        'reservations' => $reservations
    ];

    return createJsonResponse($response, $data);
});

DEL offer:123
DEL offer:123:reservations

// Endpoint para eliminar una oferta
$app->delete($prefix . '/offers/{product_id}', function (RequestInterface $request, ResponseInterface $response, array $args) use ($redis) {
    $product_id = $args['product_id'];
    $offer_key = "offer:$product_id";

    if (!$redis->exists($offer_key)) {
        $data = [
            'status' => 404,
            'message' => 'Offer not found'
        ];
        return createJsonResponse($response->withStatus(404), $data);
    }

    // Eliminar la oferta y las reservas asociadas en Redis
    $redis->del($offer_key);
    $redis->del("$offer_key:reservations");

    $data = [
        'status' => 200,
        'message' => 'Offer deleted successfully'
    ];

    return createJsonResponse($response, $data);
});

// Interceptar todas las rutas no definidas
$app->any('{routes:.+}', function (RequestInterface $request, ResponseInterface $response) {
    $data = [
        'status' => 404,
        'message' => 'Route not found'
    ];
    return createJsonResponse($response->withStatus(404), $data);
});