Eureka

This component is used to discover services for the purpose of load balancing and failover of middle-tier servers.

<dependency>
    <groupId>org.seedstack.addons.netflix</groupId>
    <artifactId>netflix-eureka</artifactId>
    <version>1.2.2</version>
</dependency>

dependencies {
    compile("org.seedstack.addons.netflix:netflix-eureka:1.2.2")
}

How to use

First, you need a Eureka server running. This server will be used by your clients to contact the right services. See this link to learn how to configure and build the server : https://github.com/Netflix/eureka/wiki/Building-Eureka-Client-and-Server

Then, you can inject the object EurekaClient in your code, which will have been created from the configuration.

public class MyService {
    @Inject
    private EurekaClient eurekaClient;

    public void service() {
        String vipAddress = "myservice.mydomain.net";
        InstanceInfo nextServerInfo = null;

        while(nextServerInfo == null) {
            try {
                nextServerInfo = this.eurekaClient.getNextServerFromEureka(vipAddress, false);
            } catch (Throwable t) {
                System.out.println("Waiting ... verifying service registration with eureka ...");
                Thread.sleep(10000L);
            }
        }
        // do something with nextServerInfo
        ...
    }
}

Configuration

You can configure the two objects used in an Eureka architecture that are the service and the client. To configure your instance of the service:

eureka:
  instance:
    appname: sampleegisteringService
    virtualHostName: myservice.mydomain.net

To configure your client:

eureka:
  client:
    shouldPreferSameZoneEureka: true
    shouldUseDnsForFetchingServiceUrls: false
    eurekaServerServiceUrls: http://localhost:8080/eureka/v2/
    decoderName: JacksonJson
    region: default

A lot of options are available, please refer to EurekaConfig.java for more information.