feat(openchallenges): configure the Eureka instance of the API Gateway (

#2769)

apps/openchallenges/api-gateway/src/main/java/org/sagebionetworks/openchallenges/api/gateway/config/EurekaInstanceConfiguration.java

@@ -0,0 +1,50 @@
+package org.sagebionetworks.openchallenges.api.gateway.config;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.cloud.commons.util.InetUtils;
+import org.springframework.cloud.netflix.eureka.EurekaInstanceConfigBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class EurekaInstanceConfiguration {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(EurekaInstanceConfiguration.class);
+
+  @Value("${server.port}")
+  private String port;
+
+  /**
+   * If the application is planned to be deployed to an AWS cloud, the Eureka instance must be
+   * configured to be AWS-aware. This can be done by customizing the EurekaInstanceConfigBean.
+   *
+   * @see <a
+   *     href="https://medium.com/@harsugangwar/microservices-with-eureka-on-aws-ecs-a-guide-to-service-discovery-and-ci-with-aws-codebuild-0478a4a71ba2">Microservices
+   *     with Eureka on AWS ECS: A Guide to Service Discovery and CI with AWS CodeBuild</a>
+   */
+  @Bean
+  @ConditionalOnProperty(
+      value = "openchallenges-api-gateway-service.is-deployed-on-aws",
+      havingValue = "true",
+      matchIfMissing = false)
+  public EurekaInstanceConfigBean eurekaInstanceConfig(InetUtils inetUtils) {
+    LOGGER.info("Configuring the Eureka instance for AWS.");
+    EurekaInstanceConfigBean bean = new EurekaInstanceConfigBean(inetUtils);
+    String ip = null;
+    try {
+      ip = InetAddress.getLocalHost().getHostAddress();
+    } catch (UnknownHostException e) {
+      LOGGER.error("Unable to get the host address.", e);
+    }
+    bean.setIpAddress(ip);
+    bean.setPreferIpAddress(true);
+    bean.setNonSecurePortEnabled(true);
+    bean.setNonSecurePort(Integer.parseInt(port));
+    return bean;
+  }
+}