What Is a Service Registry?

A service registry is a central database where services register themselves so they can be easily discovered by other services. It acts as a directory, letting your applications find each other without hardcoding addresses. This is essential in microservices environments, where services often change locations or scale dynamically.

Role in Service Discovery

Service discovery is the process of automatically locating services in your system. The service registry enables this by:

• Allowing services to register their network locations;
• Letting clients query for available services;
• Keeping track of service health and removing failed services from the list.

With a service registry, you avoid manual configuration and make your system more resilient and scalable.

Common Service Registry Examples

Two popular service registries are:

• Eureka: A service registry developed by Netflix, widely used with Spring Cloud.
• Consul: A tool from HashiCorp that offers service discovery, health checking, and more.

Querying Services

Once services are registered, other applications can discover them using the registry. For example, with Eureka, a client can look up available services by name and connect to them dynamically.

Service registries like Eureka and Consul make your microservices architecture flexible and reliable by handling service locations automatically.