conditional sidecar autoconfig EurekaInstanceConfigBean (#3568)

fix for gh-3545

spring-cloud-netflix-sidecar/src/main/java/org/springframework/cloud/netflix/sidecar/EnableSidecar.java

@@ -34,7 +34,7 @@ import org.springframework.context.annotation.Import;
 @Target(ElementType.TYPE)
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
-@Import(SidecarConfiguration.class)
+@Import(SidecarMarkerConfiguration.class)
 public @interface EnableSidecar {
 
 }

spring-cloud-netflix-sidecar/src/main/java/org/springframework/cloud/netflix/sidecar/SidecarAutoConfiguration.java

@@ -27,6 +27,8 @@ import org.apache.http.impl.client.HttpClients;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.autoconfigure.AutoConfigureBefore;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingClass;
@@ -35,6 +37,7 @@ import org.springframework.boot.context.properties.EnableConfigurationProperties
 import org.springframework.boot.web.client.RestTemplateBuilder;
 import org.springframework.cloud.client.actuator.HasFeatures;
 import org.springframework.cloud.commons.util.InetUtils;
+import org.springframework.cloud.netflix.eureka.EurekaClientAutoConfiguration;
 import org.springframework.cloud.netflix.eureka.EurekaInstanceConfigBean;
 import org.springframework.cloud.netflix.eureka.metadata.DefaultManagementMetadataProvider;
 import org.springframework.cloud.netflix.eureka.metadata.ManagementMetadata;
@@ -68,19 +71,16 @@ import static org.springframework.cloud.commons.util.IdUtils.getDefaultInstanceI
  * @see EurekaInstanceConfigBeanConfiguration
  */
 @Configuration
-@EnableConfigurationProperties
+@ConditionalOnBean(SidecarMarkerConfiguration.Marker.class)
+@EnableConfigurationProperties(SidecarProperties.class)
+@AutoConfigureBefore(EurekaClientAutoConfiguration.class)
 @ConditionalOnProperty(value = "spring.cloud.netflix.sidecar.enabled",
 		matchIfMissing = true)
-public class SidecarConfiguration {
+public class SidecarAutoConfiguration {
 
 	@Bean
 	public HasFeatures Feature() {
-		return HasFeatures.namedFeature("Netflix Sidecar", SidecarConfiguration.class);
-	}
-
-	@Bean
-	public SidecarProperties sidecarProperties() {
-		return new SidecarProperties();
+		return HasFeatures.namedFeature("Netflix Sidecar", SidecarAutoConfiguration.class);
 	}
 
 	@Bean
@@ -148,6 +148,7 @@ public class SidecarConfiguration {
 		}
 
 		@Bean
+		@ConditionalOnMissingBean
 		public EurekaInstanceConfigBean eurekaInstanceConfigBean(
 				ManagementMetadataProvider managementMetadataProvider) {
 			EurekaInstanceConfigBean config = new EurekaInstanceConfigBean(inetUtils);

spring-cloud-netflix-sidecar/src/main/java/org/springframework/cloud/netflix/sidecar/SidecarMarkerConfiguration.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2013-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cloud.netflix.sidecar;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * Annotation to activate Eureka Server related configuration.
+ * {@link SidecarAutoConfiguration}
+ *
+ * @author Greg Adams
+ */
+@Configuration
+public class SidecarMarkerConfiguration {
+
+	@Bean
+	public Marker sidecarMarkerBean() {
+		return new Marker();
+	}
+
+	class Marker {
+
+	}
+}

spring-cloud-netflix-sidecar/src/main/resources/META-INF/spring.factories

@@ -0,0 +1,2 @@
+org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
+  org.springframework.cloud.netflix.sidecar.SidecarAutoConfiguration

spring-cloud-netflix-sidecar/src/test/java/org/springframework/cloud/netflix/sidecar/SidecarApplicationTests.java

@@ -20,8 +20,12 @@ import org.junit.Test;
 import org.junit.runner.RunWith;
 
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.test.context.SpringBootTest;
+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;
 import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.web.client.RestTemplate;
 
@@ -191,4 +195,32 @@ public class SidecarApplicationTests {
 
 	}
 
+	@RunWith(SpringRunner.class)
+	@SpringBootTest(classes = EurekaInstanceConfigBeanOverrideApplication.class, webEnvironment = RANDOM_PORT)
+	public static class EurekaInstanceConfigBeanOverrideTest {
+
+		@Autowired
+		EurekaInstanceConfigBean config;
+
+		@Test
+		public void testEurekaConfigBeanOverride() {
+			assertThat(this.config.getHostname()).isEqualTo("overridden");
+		}
+
+	}
+
+	@Configuration
+	@EnableAutoConfiguration
+	@EnableSidecar
+	protected static class EurekaInstanceConfigBeanOverrideApplication {
+
+		@Bean
+		public EurekaInstanceConfigBean eurekaInstanceConfigBean(InetUtils inetUtils) {
+			EurekaInstanceConfigBean eurekaInstanceConfigBean = new EurekaInstanceConfigBean(inetUtils);
+			eurekaInstanceConfigBean.setHostname("overridden");
+			return eurekaInstanceConfigBean;
+		}
+
+	}
+
 }