Discovery Service

This Service is a personilzed implementation of Eureka and acts as a discovery hub for any microservice that sends its registration signature.

Features

• Register microservices
• Send updated information about the registered microservices

Open source being used

The Configuration Service uses a number of open source projects to work properly:

• Spring Framework
• OpenJDK
• Eureka
• Gradle
• Docker

Running the service

The Configuration Service requires Docker v18+ to run.

Once Docker is installed you can build from source or use the predefined images available at Docker Hub

Building from source

Using gradle wrapper:

cd discovery-service
./gradlew clean build
docker-compose -f docker-compose-local.yml up --build

This will build the application and generate the jar file to be placed in a container and also run a personalized version of Eureka called discovery-service.

Using Docker Hub images

The Configuration Service is very easy to run from the images on Docker Hub.

By default, Docker will expose port 8888. You can change this within the docker-compose.yml file if necessary.

cd configuration-service
docker-compose up

Client configuration

In order for the Java Spring client applications register themselves in the discovery service, they need to have the following configurations in Application.java, application.yml and gradle.build.

Application.java

The @EnableEurekaClient annotation must be present in the main Application.java.

...
@EnableEurekaClient
public class Application {
...

application.yml

The application.yml file needs to be configured as instructed below:

eureka:
  instance:
    preferIpAddress: true
  client:
    registerWithEureka: true
    fetchRegistry: true
    serviceUrl:
        defaultZone: http://${DOCKER_MACHINE_IP:discoveryservice}:8761/eureka/

build.gradle

The build.gradle file must contain the next configuration:

ext {
    springCloudVersion = 'Edgware.SR2'
}
...
dependencies {
...
    compile('org.springframework.cloud:spring-cloud-starter-eureka')
...
}
...
dependencyManagement {
	imports {
		mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
	}
}