Service Registry: Register, Health Check, Discover

A new service instance starts up but nobody knows it exists until it registers, passes a health check, and becomes discoverable by other services. Without a registry, you hard-code URLs and deployments break whenever instances scale. This workflow registers the service at its URL, runs a health check (12ms latency), and confirms the service is discoverable with 3 instances.

Workflow

serviceName, serviceUrl, version
               |
               v
+-------------------------+     +-------------------+     +------------------------+
| sr_register_service     | --> | sr_health_check   | --> | sr_discover_service    |
+-------------------------+     +-------------------+     +------------------------+
  registrationId generated       healthy: true              endpoint:
  registered: true               latencyMs: 12              {serviceName}.internal:8080
                                                            instances: 3

Workers

RegisterServiceWorker -- Registers serviceName at serviceUrl. Returns a registrationId, registered: true.

HealthCheckWorker -- Checks serviceUrl. Returns healthy: true, latencyMs: 12.

DiscoverServiceWorker -- Discovers the service from the registry. Returns endpoint: "{serviceName}.internal:8080" with instances: 3 available for load balancing.

Tests

23 unit tests cover registration, health checking, and service discovery. The workflow accepts serviceName, serviceUrl, and version as inputs.

Running

See ../../RUNNING.md for setup and execution instructions.