# Health Endpoints Quick Reference

## API Gateway HTTP Endpoints

| Endpoint       | Purpose         | Response                                         | Status Codes             |
| -------------- | --------------- | ------------------------------------------------ | ------------------------ |
| `GET /healthz` | Liveness probe  | `{"status": "ok"}`                               | 200 OK                   |
| `GET /readyz`  | Readiness probe | `{"status": "ready", "dependencies": {...}}`     | 200 OK / 503 Unavailable |
| `GET /health`  | Detailed health | `{"status": "healthy", "timestamp": "...", ...}` | 200 OK                   |

## Core Service gRPC Health

| Service                 | Method    | Response                  |
| ----------------------- | --------- | ------------------------- |
| `grpc.health.v1.Health` | `Check()` | `SERVING` / `NOT_SERVING` |

## Kubernetes Probes

### Gateway

| Probe     | Endpoint   | Delay | Period | Timeout | Failures |
| --------- | ---------- | ----- | ------ | ------- | -------- |
| Liveness  | `/healthz` | 10s   | 10s    | 5s      | 3        |
| Readiness | `/readyz`  | 5s    | 5s     | 3s      | 2        |
| Startup   | `/healthz` | 0s    | 2s     | 5s      | 30       |

### Core Service

| Probe     | Type | Delay | Period | Timeout | Failures |
| --------- | ---- | ----- | ------ | ------- | -------- |
| Liveness  | gRPC | 15s   | 20s    | 5s      | 3        |
| Readiness | gRPC | 5s    | 10s    | 3s      | 2        |

## Docker Compose Health Checks

| Service     | Test Command                            | Interval | Timeout | Retries |
| ----------- | --------------------------------------- | -------- | ------- | ------- |
| db          | `pg_isready -U user -d aura_db`         | 5s       | 5s      | 5       |
| core        | `grpc_health_probe -addr=:50051`        | 10s      | 5s      | 3       |
| api-gateway | `curl -f http://localhost:8000/healthz` | 10s      | 5s      | 3       |
| frontend    | `curl -f http://localhost:3000`         | 10s      | 5s      | 3       |

## Testing Commands

```bash
# HTTP endpoints
curl http://localhost:8000/healthz
curl http://localhost:8000/readyz
curl http://localhost:8000/health

# gRPC health
grpc_health_probe -addr=localhost:50051

# Docker Compose status
docker-compose ps

# Kubernetes pod status
kubectl get pods -l app=gateway
kubectl get pods -l app=core
```

## Dependencies Checked

| Service      | Checks                                      |
| ------------ | ------------------------------------------- |
| API Gateway  | Core Service gRPC connectivity (5s timeout) |
| Core Service | PostgreSQL connectivity (`SELECT 1`)        |

## Response Examples

### `/healthz` (Liveness)

```json
{
  "status": "ok"
}
```

### `/readyz` (Readiness - Healthy)

```json
{
  "status": "ready",
  "dependencies": {
    "core_service": "ok"
  }
}
```

### `/readyz` (Readiness - Unhealthy)

```json
{
  "status": "not_ready",
  "dependencies": {
    "core_service": "timeout"
  }
}
```

*Status Code: 503 Service Unavailable*

### `/health` (Detailed)

```json
{
  "status": "healthy",
  "timestamp": "2026-01-27T12:34:56.789012+00:00",
  "version": "0.1.0",
  "checks": {
    "api_gateway": "ok",
    "core_service": "ok"
  }
}
```

### gRPC Health Check

```
status: SERVING
```