Health Check : First line of Defense

Confused about health checks? Let’s break it down in plain terms.

What Is a Health Check?

A health check is a simple way to ask your application: “Are you okay?”

• It’s like a heartbeat monitor for your app.
• Returns a status (e.g., UP, DOWN) and details about critical components (database, APIs, disk space).

When Should You Use Health Checks?

• During deployments: Ensure new versions are running smoothly.
• Monitoring: Track uptime and spot failures (e.g., with tools like Prometheus).
• Auto-scaling: Cloud platforms (AWS, Kubernetes) use health checks to add/remove instances.
• Self-healing: Automatically restart failed services.

What Data Can You Get?

Most frameworks provide:

1. Status: UP, DOWN, or UNKNOWN.
2. Dependencies: Database, external APIs, cache.
3. System metrics: Disk space, memory usage.
4. Custom checks: Integrate business logic (e.g., “Is payment gateway reachable?”).

Stop Reinventing the Wheel!

Most modern frameworks already include health checks, no need to build your own!

Spring Boot Best Practices

1. Leverage Spring Boot Actuator

Spring Boot’s built-in Actuator module provides a /actuator/health endpoint out of the box. Enable it with:

implementation 'org.springframework.boot:spring-boot-starter-actuator'        

2. Expose ONLY what’s needed:

management.endpoints.web.exposure.include=health,info 
management.endpoints.web.exposure.exclude=env,beans 
          

3. Secure Your Endpoints

Use Spring Security to restrict /actuator/** to admins/internal networks.

Never expose heapdump, env, or metrics publicly!

4. Optimize Performance with Caching

Prevent frequent health checks from overloading your app. Cache results:

management.endpoint.health.cache.time-to-live=10s        

Health Checks in Other Frameworks

• .NET Core : Health Checks
• Node.js (Express) : express-healthcheck
• Django (Python) : django-health-check

Health checks are your app’s first line of defense. Set them up once, and let them silently guard your system!