---
id: INT-014
type: Integration
title: "Webhooks Outbound"
provider: "BullMQ"
status: Planificado
integration_type: "events"
created_at: 2026-01-10
updated_at: 2026-01-10
simco_version: "4.0.1"
tags:
  - webhooks
  - events
  - bullmq
  - integration
  - outbound
---

# INT-014: Webhooks Outbound

## Metadata

| Campo | Valor |
|-------|-------|
| **Codigo** | INT-014 |
| **Proveedor** | BullMQ (interno) |
| **Tipo** | Eventos |
| **Estado** | Planificado |
| **Multi-tenant** | Si |
| **Epic Relacionada** | MCH-029 |
| **Owner** | Backend Team |

---

## 1. Descripcion

Sistema de webhooks outbound que permite a tenants recibir notificaciones HTTP cuando ocurren eventos en el sistema. Incluye firma de payloads, reintentos con backoff y logs de entrega.

**Casos de uso principales:**
- Notificar sistemas externos de nuevos pedidos
- Sincronizar inventario con ERP
- Integraciones con Zapier/Make
- Alertas personalizadas

---

## 2. Eventos Disponibles

### Eventos por Categoria

| Categoria | Evento | Payload |
|-----------|--------|---------|
| **Orders** | order.created | Order completa |
| | order.updated | Order con cambios |
| | order.completed | Order finalizada |
| | order.cancelled | Order cancelada |
| **Products** | product.created | Producto nuevo |
| | product.updated | Producto modificado |
| | product.deleted | Producto eliminado |
| | product.low_stock | Stock bajo minimo |
| **Payments** | payment.received | Pago recibido |
| | payment.failed | Pago fallido |
| | payment.refunded | Pago reembolsado |
| **Customers** | customer.created | Cliente nuevo |
| | customer.updated | Cliente modificado |

---

## 3. Configuracion de Endpoints

### API de Configuracion

```typescript
// POST /api/webhooks/endpoints
{
  "url": "https://example.com/webhook",
  "events": ["order.created", "payment.received"],
  "secret": "whsec_xxxxxxxx", // Generado si no se provee
  "description": "Mi integracion",
  "is_active": true
}

// Response
{
  "id": "wh_123abc",
  "url": "https://example.com/webhook",
  "events": ["order.created", "payment.received"],
  "secret": "whsec_xxxxxxxx",
  "is_active": true,
  "created_at": "2026-01-10T10:00:00Z"
}
```

### Endpoints CRUD

| Metodo | Ruta | Descripcion |
|--------|------|-------------|
| GET | /api/webhooks/endpoints | Listar endpoints |
| POST | /api/webhooks/endpoints | Crear endpoint |
| GET | /api/webhooks/endpoints/:id | Obtener endpoint |
| PATCH | /api/webhooks/endpoints/:id | Actualizar endpoint |
| DELETE | /api/webhooks/endpoints/:id | Eliminar endpoint |
| GET | /api/webhooks/deliveries | Listar entregas |
| POST | /api/webhooks/endpoints/:id/test | Enviar test |

---

## 4. Payload de Webhook

### Estructura

```json
{
  "id": "evt_123abc",
  "type": "order.created",
  "created_at": "2026-01-10T10:00:00Z",
  "data": {
    "id": "ord_456def",
    "total": 150.00,
    "items": [...],
    "customer": {...}
  },
  "tenant_id": "550e8400-e29b-41d4-a716-446655440000"
}
```

### Headers

| Header | Valor | Descripcion |
|--------|-------|-------------|
| `Content-Type` | application/json | Tipo de contenido |
| `X-Webhook-Id` | evt_123abc | ID del evento |
| `X-Webhook-Timestamp` | 1704880800 | Unix timestamp |
| `X-Webhook-Signature` | sha256=xxx | Firma HMAC |
| `User-Agent` | MiChangarrito/1.0 | Identificador |

---

## 5. Firma de Payloads

### Generacion de Firma

```typescript
function signPayload(
  payload: string,
  secret: string,
  timestamp: number,
): string {
  const signedPayload = `${timestamp}.${payload}`;
  const signature = crypto
    .createHmac('sha256', secret)
    .update(signedPayload)
    .digest('hex');

  return `sha256=${signature}`;
}
```

### Verificacion en Cliente

```typescript
// Ejemplo para el receptor del webhook
function verifySignature(
  payload: string,
  signature: string,
  secret: string,
  timestamp: number,
  tolerance: number = 300, // 5 minutos
): boolean {
  const currentTime = Math.floor(Date.now() / 1000);

  // Verificar que no sea muy viejo
  if (currentTime - timestamp > tolerance) {
    throw new Error('Timestamp too old');
  }

  const expected = signPayload(payload, secret, timestamp);
  return crypto.timingSafeEqual(
    Buffer.from(signature),
    Buffer.from(expected),
  );
}
```

---

## 6. Estrategia de Reintentos

### Exponential Backoff

```
Intento 1: Inmediato
Intento 2: 1 segundo
Intento 3: 2 segundos
Intento 4: 4 segundos
Intento 5: 8 segundos
Intento 6: 16 segundos (maximo)
```

### Configuracion BullMQ

```typescript
await this.webhookQueue.add('deliver', {
  endpointId: endpoint.id,
  eventId: event.id,
  payload: event.data,
}, {
  attempts: 6,
  backoff: {
    type: 'exponential',
    delay: 1000,
  },
  removeOnComplete: true,
  removeOnFail: false, // Mantener para logs
});
```

### Codigos de Respuesta

| Codigo | Accion | Descripcion |
|--------|--------|-------------|
| 2xx | Exito | Entrega exitosa |
| 3xx | Retry | Seguir redirecciones |
| 4xx | Fallo | No reintentar (excepto 429) |
| 429 | Retry | Rate limited, esperar |
| 5xx | Retry | Error del servidor |
| Timeout | Retry | Esperar siguiente intento |

---

## 7. Tabla de BD

### Schema webhooks

```sql
CREATE SCHEMA IF NOT EXISTS webhooks;

CREATE TABLE webhooks.endpoints (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    tenant_id UUID NOT NULL,
    url VARCHAR(2000) NOT NULL,
    description VARCHAR(255),
    events TEXT[] NOT NULL,
    secret VARCHAR(255) NOT NULL,
    is_active BOOLEAN DEFAULT true,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

CREATE TABLE webhooks.deliveries (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    endpoint_id UUID REFERENCES webhooks.endpoints(id),
    event_type VARCHAR(100) NOT NULL,
    event_id VARCHAR(100) NOT NULL,
    payload JSONB NOT NULL,
    status VARCHAR(20) NOT NULL, -- pending, success, failed
    attempts INTEGER DEFAULT 0,
    last_attempt_at TIMESTAMP WITH TIME ZONE,
    response_status INTEGER,
    response_body TEXT,
    error_message TEXT,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    completed_at TIMESTAMP WITH TIME ZONE
);

CREATE INDEX idx_deliveries_endpoint ON webhooks.deliveries(endpoint_id);
CREATE INDEX idx_deliveries_status ON webhooks.deliveries(status);
```

---

## 8. Procesador de Webhooks

```typescript
@Processor('webhooks')
export class WebhookProcessor {
  constructor(
    private readonly httpService: HttpService,
    private readonly webhookService: WebhookService,
  ) {}

  @Process('deliver')
  async handleDelivery(job: Job<WebhookJobData>) {
    const { endpointId, eventId, payload } = job.data;

    const endpoint = await this.webhookService.getEndpoint(endpointId);
    if (!endpoint.is_active) return;

    const timestamp = Math.floor(Date.now() / 1000);
    const payloadString = JSON.stringify(payload);
    const signature = this.signPayload(payloadString, endpoint.secret, timestamp);

    try {
      const response = await this.httpService.axiosRef.post(
        endpoint.url,
        payload,
        {
          headers: {
            'Content-Type': 'application/json',
            'X-Webhook-Id': eventId,
            'X-Webhook-Timestamp': timestamp.toString(),
            'X-Webhook-Signature': signature,
            'User-Agent': 'MiChangarrito/1.0',
          },
          timeout: 30000, // 30 segundos
        },
      );

      await this.webhookService.logDelivery(endpointId, eventId, {
        status: 'success',
        responseStatus: response.status,
        attempts: job.attemptsMade + 1,
      });

    } catch (error) {
      const shouldRetry = this.shouldRetry(error);

      await this.webhookService.logDelivery(endpointId, eventId, {
        status: shouldRetry ? 'pending' : 'failed',
        responseStatus: error.response?.status,
        errorMessage: error.message,
        attempts: job.attemptsMade + 1,
      });

      if (shouldRetry) {
        throw error; // BullMQ reintentara
      }
    }
  }

  private shouldRetry(error: any): boolean {
    if (!error.response) return true; // Timeout o network error
    const status = error.response.status;
    return status === 429 || status >= 500;
  }
}
```

---

## 9. UI de Administracion

### Funcionalidades

- Lista de endpoints configurados
- Crear/editar/eliminar endpoints
- Ver historial de entregas
- Reintentar entregas fallidas
- Enviar evento de prueba
- Rotar secret

### Ejemplo de Vista

```
+--------------------------------------------------+
| Webhooks                              [+ Nuevo]  |
+--------------------------------------------------+
| URL                    | Eventos      | Estado   |
|------------------------|--------------|----------|
| https://example.com/wh | order.*      | Activo   |
| https://zapier.com/... | payment.*    | Activo   |
| https://erp.local/api  | product.*    | Inactivo |
+--------------------------------------------------+

Entregas Recientes:
+--------------------------------------------------+
| Evento          | Destino      | Estado | Fecha  |
|-----------------|--------------|--------|--------|
| order.created   | example.com  | OK     | 10:00  |
| payment.failed  | zapier.com   | OK     | 09:55  |
| product.updated | erp.local    | Failed | 09:50  |
+--------------------------------------------------+
```

---

## 10. Testing

### Enviar Evento de Prueba

```typescript
// POST /api/webhooks/endpoints/:id/test
{
  "event_type": "test.webhook"
}

// Payload enviado
{
  "id": "evt_test_123",
  "type": "test.webhook",
  "created_at": "2026-01-10T10:00:00Z",
  "data": {
    "message": "This is a test webhook"
  }
}
```

### Herramientas de Debug

- [webhook.site](https://webhook.site) - Receptor de prueba
- [ngrok](https://ngrok.com) - Tunel para localhost

---

## 11. Monitoreo

### Metricas

| Metrica | Descripcion | Alerta |
|---------|-------------|--------|
| webhook_deliveries_total | Total entregas | - |
| webhook_deliveries_success | Entregas exitosas | - |
| webhook_deliveries_failed | Entregas fallidas | > 10% |
| webhook_delivery_latency | Latencia de entrega | > 5s |
| webhook_queue_length | Jobs pendientes | > 100 |

---

## 12. Referencias

- [Webhooks Best Practices](https://webhooks.dev/best-practices)
- [BullMQ Documentation](https://docs.bullmq.io/)
- [Stripe Webhooks](https://stripe.com/docs/webhooks) (referencia)
- [ADR-0007: Webhook Retry Strategy](../97-adr/ADR-0007-webhook-retry-strategy.md)

---

**Ultima actualizacion:** 2026-01-10
**Autor:** Backend Team