Prueba Técnica

Código a revisar

<?php

namespace App\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\JsonResponse;
use Symfony\Component\Routing\Annotation\Route;
use Doctrine\ORM\EntityManagerInterface;

class AffiliateController extends AbstractController
{
    #[Route('/api/affiliates/register', methods: ['POST'])]
    public function register(Request $request, EntityManagerInterface $em): JsonResponse
    {
        $data = json_decode($request->getContent(), true);

        // Check if email already exists
        $existing = $em->getConnection()->executeQuery(
            "SELECT * FROM affiliates WHERE email = '" . $data['email'] . "'"
        )->fetchAssociative();

        if ($existing) {
            return new JsonResponse(['error' => 'Email already exists'], 400);
        }

        $password = md5($data['password']);

        $em->getConnection()->executeStatement(
            "INSERT INTO affiliates (name, email, password, country, created_at)
             VALUES ('" . $data['name'] . "',
                     '" . $data['email'] . "',
                     '" . $password . "',
                     '" . $data['country'] . "',
                     '" . date('Y-m-d H:i:s') . "')"
        );

        $affiliateId = $em->getConnection()->lastInsertId();

        // Assign default commission program
        $program = $em->getConnection()->executeQuery(
            "SELECT * FROM commission_programs WHERE is_default = 1"
        )->fetchAssociative();

        if ($program) {
            $em->getConnection()->executeStatement(
                "INSERT INTO affiliate_programs (affiliate_id, program_id, assigned_at)
                 VALUES (" . $affiliateId . ", " . $program['id'] . ", NOW())"
            );
        }

        // Send welcome email
        $mailer = new \App\Service\MailerService();
        $mailer->send(
            $data['email'],
            'Welcome to Betandeal!',
            'welcome_affiliate',
            ['name' => $data['name'], 'program' => $program['name'] ?? 'Standard']
        );

        // Log the registration
        file_put_contents(
            '/var/log/affiliates.log',
            date('Y-m-d H:i:s') . ' - New affiliate: ' . $data['email'] . "\n",
            FILE_APPEND
        );

        return new JsonResponse([
            'success'      => true,
            'affiliate_id' => $affiliateId,
            'program'      => $program['name'] ?? null,
        ]);
    }

    #[Route('/api/affiliates/{id}/stats', methods: ['GET'])]
    public function getStats(int $id, Request $request, EntityManagerInterface $em): JsonResponse
    {
        $from = $request->query->get('from', date('Y-m-01'));
        $to   = $request->query->get('to', date('Y-m-d'));

        $stats = $em->getConnection()->executeQuery("
            SELECT
                COUNT(c.id) as clicks,
                COUNT(cv.id) as conversions,
                SUM(cv.commission_amount) as revenue
            FROM clicks c
            LEFT JOIN conversions cv ON cv.click_id = c.id
            WHERE c.affiliate_id = $id
            AND c.created_at BETWEEN '$from' AND '$to'
        ")->fetchAssociative();

        $topOffers = $em->getConnection()->executeQuery("
            SELECT o.name, COUNT(c.id) as clicks
            FROM clicks c
            JOIN offers o ON o.id = c.offer_id
            WHERE c.affiliate_id = $id
            GROUP BY o.id
            ORDER BY clicks DESC
            LIMIT 5
        ")->fetchAllAssociative();

        return new JsonResponse([
            'stats'      => $stats,
            'top_offers' => $topOffers,
        ]);
    }
}

<?php

namespace App\Service;

class MailerService
{
    private $apiKey    = 'SG.live_xK92mQpLTz3nVwRb8fYoAE';
    private $fromEmail = 'noreply@betandeal.com';

    public function send($to, $subject, $template, $vars = [])
    {
        $html = file_get_contents(__DIR__ . '/../../templates/emails/' . $template . '.html');

        foreach ($vars as $key => $value) {
            $html = str_replace(' . $key . ', $value, $html);
        }

        $ch = curl_init('https://api.sendgrid.com/v3/mail/send');
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_HTTPHEADER, [
            'Authorization: Bearer ' . $this->apiKey,
            'Content-Type: application/json',
        ]);
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
            'personalizations' => [['to' => [['email' => $to]]]],
            'from'             => ['email' => $this->fromEmail],
            'subject'          => $subject,
            'content'          => [['type' => 'text/html', 'value' => $html]],
        ]));

        curl_exec($ch);
        curl_close($ch);
    }
}

El problema

El sistema actual tiene dificultades para escalar. En eventos especiales (Champions League, Grand Prix…) recibimos picos de 50.000–100.000 clics por hora. Además:

• Algunos operadores envían postbacks duplicados para la misma conversión.
• El cálculo de comisiones es síncrono y tarda hasta 2 segundos por conversión.
• Los afiliados exigen dashboards con datos casi en tiempo real (< 5 min de lag).
• Actualmente todo corre en un único servidor con PHP-FPM + MySQL.