Merge branch '2.0.x.fix' of https://github.com/aftersss/spring-cloud-netflix into aftersss-2.0.x.fix

docs/src/main/asciidoc/spring-cloud-netflix.adoc

@@ -324,6 +324,19 @@ eureka.instance.metadataMap.zone = zone2
 eureka.client.preferSameZoneEureka = true
 ```
 
+=== Refresh Scope of Eureka Client
+
+By default, the `EurekaClient` bean is refreshable, so the Eureka client properties can be refreshed, but this has a disadvantage:
+with the default setting, the `EurekaClient` instance will be destroyed and reconstructed again when refreshed, so your program will unregister from eurekaServer and after some seconds, it will register to eurekaServer again,
+consider that when we refresh all of the `Service A` instances at the same time, there will be some seconds no one instance alive on eurekaServer, if at the same time, `Service B` tries to fetch instances of `Service A`,
+it will fetch an empty list. If you don't want to see this, you can set `eureka.client.refresh.enable=false` in the application properties to make the `EurekaClient` instance immutable,
+but notice that if you set this property to false, none of the Eureka client properties will be refreshable. (This property is imported since `Finchley.SR4`)
+
+*application.properties. *
+```
+eureka.client.refresh.enable=false
+```
+
 [[spring-cloud-eureka-server]]
 == Service Discovery: Eureka Server
 

spring-cloud-netflix-eureka-client/src/main/java/org/springframework/cloud/netflix/eureka/EurekaClientAutoConfiguration.java

@@ -259,6 +259,7 @@ public class EurekaClientAutoConfiguration {
 	@Documented
 	@ConditionalOnClass(RefreshScope.class)
 	@ConditionalOnBean(RefreshAutoConfiguration.class)
+	@ConditionalOnProperty(value = "eureka.client.refresh.enable", havingValue = "true", matchIfMissing = true)
 	@interface ConditionalOnRefreshScope {
 
 	}
@@ -376,6 +377,10 @@ public class EurekaClientAutoConfiguration {
 		static class MissingScope {
 		}
 
+		@ConditionalOnProperty(value = "eureka.client.refresh.enable", havingValue = "false")
+		static class OnPropertyDisabled {
+		}
+
 	}
 
 	@Configuration

spring-cloud-netflix-eureka-client/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -6,6 +6,12 @@
       "description": "Enables the Eureka health check handler.",
       "type": "java.lang.Boolean"
     },
+    {
+      "defaultValue": true,
+      "name": "eureka.client.refresh.enable",
+      "description": "Determines whether the EurekaClient instance can be refreshed or not(If disabled none of the Eureka client properties will be refreshable).",
+      "type": "java.lang.Boolean"
+    },
     {
       "defaultValue": true,
       "name": "ribbon.eureka.enabled",
@@ -13,4 +19,4 @@
       "type": "java.lang.Boolean"
     }
   ]
-}
+}

spring-cloud-netflix-eureka-client/src/test/java/org/springframework/cloud/netflix/eureka/ConditionalOnRefreshScopeTests.java

@@ -20,6 +20,7 @@ import org.junit.Test;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
 import org.springframework.cloud.autoconfigure.RefreshAutoConfiguration;
+import org.springframework.cloud.netflix.eureka.EurekaClientAutoConfiguration.ConditionalOnMissingRefreshScope;
 import org.springframework.cloud.netflix.eureka.EurekaClientAutoConfiguration.ConditionalOnRefreshScope;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -40,6 +41,20 @@ public class ConditionalOnRefreshScopeTests {
 			assertThat(c).hasSingleBean(
 				org.springframework.cloud.context.scope.refresh.RefreshScope.class);
 			assertThat(c.getBean("foo")).isEqualTo("foo");
+			assertThat(c).doesNotHaveBean("bar");
+		});
+	}
+
+	@Test
+	public void refreshScopeIncludedAndPropertyDisabled() {
+		new ApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(RefreshAutoConfiguration.class))
+			.withPropertyValues("eureka.client.refresh.enable=false")
+			.withUserConfiguration(Beans.class).run(c -> {
+			assertThat(c).hasSingleBean(
+				org.springframework.cloud.context.scope.refresh.RefreshScope.class);
+			assertThat(c).doesNotHaveBean("foo");
+			assertThat(c.getBean("bar")).isEqualTo("bar");
 		});
 	}
 
@@ -47,6 +62,14 @@ public class ConditionalOnRefreshScopeTests {
 	public void refreshScopeNotIncluded() {
 		new ApplicationContextRunner().withUserConfiguration(Beans.class).run(c -> {
 			assertThat(c).doesNotHaveBean("foo");
+			assertThat(c.getBean("bar")).isEqualTo("bar");
+		});
+
+		new ApplicationContextRunner().withUserConfiguration(Beans.class)
+			.withPropertyValues("eureka.client.refresh.enable=false")
+			.run(c -> {
+			assertThat(c).doesNotHaveBean("foo");
+			assertThat(c.getBean("bar")).isEqualTo("bar");
 		});
 	}
 
@@ -57,6 +80,12 @@ public class ConditionalOnRefreshScopeTests {
 		public String foo() {
 			return "foo";
 		}
+
+		@Bean
+		@ConditionalOnMissingRefreshScope
+		public String bar() {
+			return "bar";
+		}
 	}
 
-}
+}