Remove ribbon integration (#691)

* Remove Ribbon-specific configuration.

* Remove Ribbon-specific docs. Refactor.

Author: OlgaMaciaszek

docs/src/main/asciidoc/_configprops.adoc

@@ -34,7 +34,6 @@
 |spring.cloud.loadbalancer.health-check.interval | 30s | Interval for rerunning the HealthCheck scheduler.
 |spring.cloud.loadbalancer.health-check.path |  | 
 |spring.cloud.loadbalancer.retry.enabled | true | 
-|spring.cloud.loadbalancer.ribbon.enabled | true | Causes `RibbonLoadBalancerClient` to be used by default.
 |spring.cloud.refresh.enabled | true | Enables autoconfiguration for the refresh scope and associated features.
 |spring.cloud.refresh.extra-refreshable | true | Additional class names for beans to post process into refresh scope.
 |spring.cloud.service-registry.auto-registration.enabled | true | Whether service auto-registration is enabled. Defaults to true.

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

@@ -389,18 +389,10 @@ CAUTION: A `RestTemplate` bean is no longer created through auto-configuration.
 Individual applications must create it.
 
 The URI needs to use a virtual host name (that is, a service name, not a host name).
-The Ribbon client is used to create a full physical address.
-See {githubroot}/spring-cloud-netflix/blob/master/spring-cloud-netflix-ribbon/src/main/java/org/springframework/cloud/netflix/ribbon/RibbonAutoConfiguration.java[`RibbonAutoConfiguration`] for the details of how the `RestTemplate` is set up.
+The BlockingLoadBalancerClient is used to create a full physical address.
 
 IMPORTANT: To use a load-balanced `RestTemplate`, you need to have a load-balancer implementation in your classpath.
-The recommended implementation is `BlockingLoadBalancerClient`.
 Add <<spring-cloud-loadbalancer-starter, Spring Cloud LoadBalancer starter>> to your project in order to use it.
-The
-`RibbonLoadBalancerClient` also can be used, but it's now under maintenance and we do not recommend adding it to new projects.
-
-WARNING:  By default, if you have both `RibbonLoadBalancerClient` and `BlockingLoadBalancerClient`, to
-preserve backward compatibility, `RibbonLoadBalancerClient` is used.
-To override it, you can set the `spring.cloud.loadbalancer.ribbon.enabled` property to `false`.
 
 [[webclinet-loadbalancer-client]]
 === Spring WebClient as a Load Balancer Client
@@ -434,29 +426,19 @@ public class MyClass {
 ====
 
 The URI needs to use a virtual host name (that is, a service name, not a host name).
-The Ribbon client or Spring Cloud LoadBalancer is used to create a full physical address.
+The Spring Cloud LoadBalancer is used to create a full physical address.
 
 IMPORTANT: If you want to use a `@LoadBalanced WebClient.Builder`, you need to have a load balancer
 implementation in the classpath. We recommend that you add the
 <<spring-cloud-loadbalancer-starter, Spring Cloud LoadBalancer starter>> to your project.
 Then, `ReactiveLoadBalancer` is used underneath.
-Alternatively, this functionality also works with `spring-cloud-starter-netflix-ribbon`, but the request
-is handled by a non-reactive `LoadBalancerClient` under the hood. Additionally,
-`spring-cloud-starter-netflix-ribbon` is already in maintenance mode, so we do not recommend
-adding it to new projects.
-If you have both `spring-cloud-starter-loadbalancer` and `spring-cloud-starter-netflix-ribbon`
-in your classpath, Ribbon is used by default. To switch to Spring Cloud LoadBalancer,
-set the `spring.cloud.loadbalancer.ribbon.enabled` property to `false`.
 
 ==== Retrying Failed Requests
 
 A load-balanced `RestTemplate` can be configured to retry failed requests.
 By default, this logic is disabled.
 You can enable it by adding link:https://github.com/spring-projects/spring-retry[Spring Retry] to your application's classpath.
-The load-balanced `RestTemplate` honors some of the Ribbon configuration values related to retrying failed requests.
-You can use `client.ribbon.MaxAutoRetries`, `client.ribbon.MaxAutoRetriesNextServer`, and `client.ribbon.OkToRetryOnAllOperations` properties.
 If you would like to disable the retry logic with Spring Retry on the classpath, you can set `spring.cloud.loadbalancer.retry.enabled=false`.
-See the https://github.com/Netflix/ribbon/wiki/Getting-Started#the-properties-file-sample-clientproperties[Ribbon documentation] for a description of what these properties do.
 
 If you would like to implement a `BackOffPolicy` in your retries, you need to create a bean of type `LoadBalancedRetryFactory` and override the `createBackOffPolicy` method:
 
@@ -478,8 +460,6 @@ public class MyConfiguration {
 ----
 ====
 
-NOTE: `client` in the preceding examples should be replaced with your Ribbon client's name.
-
 If you want to add one or more `RetryListener` implementations to your retry functionality, you need to
 create a bean of type `LoadBalancedRetryListenerFactory` and return the `RetryListener` array
 you would like to use for a given service, as the following example shows:
@@ -649,16 +629,9 @@ public class MyClass {
 The URI needs to use a virtual host name (that is, a service name, not a host name).
 The `ReactorLoadBalancer` is used to create a full physical address.
 
-NOTE: By default, if you have `spring-cloud-netflix-ribbon` in your classpath, <<load-balancer-exchange-filter-function,`LoadBalancerExchangeFilterFunction`>>
-is used to maintain backward compatibility. To use
-`ReactorLoadBalancerExchangeFilterFunction`, set the `spring.cloud.loadbalancer.ribbon.enabled` property
-to `false`.
-
 [[load-balancer-exchange-filter-function]]
 ==== Spring WebFlux `WebClient` with a Non-reactive Load Balancer Client
 
-If you you do not have <<spring-cloud-loadbalancer-starter, Spring Cloud LoadBalancer starter>> in your project
-but you do have spring-cloud-starter-netflix-ribbon, you can still use `WebClient` with `LoadBalancerClient`.
 If `spring-webflux` is on the classpath, `LoadBalancerExchangeFilterFunction`
 is auto-configured. Note, however, that this
 uses a non-reactive client under the hood.
@@ -1004,9 +977,6 @@ NOTE: Spring Cloud LoadBalancer starter includes
 https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-caching.html[Spring Boot Caching]
 and https://github.com/stoyanr[Evictor].
 
-WARNING: If you have both Ribbon and Spring Cloud LoadBalancer int the classpath, in order to maintain backward compatibility, Ribbon-based implementations will be used by default.
-In order to switch to using Spring Cloud LoadBalancer under the hood, make sure you set the property `spring.cloud.loadbalancer.ribbon.enabled` to `false`.
-
 [[custom-loadbalancer-configuration]]
 === Passing Your Own Spring Cloud LoadBalancer Configuration
 

spring-cloud-commons/src/main/java/org/springframework/cloud/client/loadbalancer/AsyncLoadBalancerAutoConfiguration.java

@@ -30,7 +30,7 @@
 import org.springframework.web.client.AsyncRestTemplate;
 
 /**
- * Auto-configuration for Ribbon (client-side load balancing).
+ * Auto-configuration for blocking client-side load balancing.
  *
  * @author Rob Worsnop
  */
@@ -49,13 +49,10 @@ static class AsyncRestTemplateCustomizerConfig {
 		@Bean
 		public SmartInitializingSingleton loadBalancedAsyncRestTemplateInitializer(
 				final List<AsyncRestTemplateCustomizer> customizers) {
-			return new SmartInitializingSingleton() {
-				@Override
-				public void afterSingletonsInstantiated() {
-					for (AsyncRestTemplate restTemplate : AsyncRestTemplateCustomizerConfig.this.restTemplates) {
-						for (AsyncRestTemplateCustomizer customizer : customizers) {
-							customizer.customize(restTemplate);
-						}
+			return () -> {
+				for (AsyncRestTemplate restTemplate : AsyncRestTemplateCustomizerConfig.this.restTemplates) {
+					for (AsyncRestTemplateCustomizer customizer : customizers) {
+						customizer.customize(restTemplate);
 					}
 				}
 			};
@@ -75,14 +72,11 @@ public AsyncLoadBalancerInterceptor asyncLoadBalancerInterceptor(
 		@Bean
 		public AsyncRestTemplateCustomizer asyncRestTemplateCustomizer(
 				final AsyncLoadBalancerInterceptor loadBalancerInterceptor) {
-			return new AsyncRestTemplateCustomizer() {
-				@Override
-				public void customize(AsyncRestTemplate restTemplate) {
-					List<AsyncClientHttpRequestInterceptor> list = new ArrayList<>(
-							restTemplate.getInterceptors());
-					list.add(loadBalancerInterceptor);
-					restTemplate.setInterceptors(list);
-				}
+			return restTemplate -> {
+				List<AsyncClientHttpRequestInterceptor> list = new ArrayList<>(
+						restTemplate.getInterceptors());
+				list.add(loadBalancerInterceptor);
+				restTemplate.setInterceptors(list);
 			};
 		}
 

spring-cloud-commons/src/main/java/org/springframework/cloud/client/loadbalancer/LoadBalancerAutoConfiguration.java

@@ -35,7 +35,7 @@
 import org.springframework.web.client.RestTemplate;
 
 /**
- * Auto-configuration for Ribbon (client-side load balancing).
+ * Auto-configuration for blocking (client-side load balancing).
  *
  * @author Spencer Gibb
  * @author Dave Syer
@@ -79,7 +79,7 @@ public LoadBalancerRequestFactory loadBalancerRequestFactory(
 	static class LoadBalancerInterceptorConfig {
 
 		@Bean
-		public LoadBalancerInterceptor ribbonInterceptor(
+		public LoadBalancerInterceptor loadBalancerInterceptor(
 				LoadBalancerClient loadBalancerClient,
 				LoadBalancerRequestFactory requestFactory) {
 			return new LoadBalancerInterceptor(loadBalancerClient, requestFactory);
@@ -124,7 +124,7 @@ public static class RetryInterceptorAutoConfiguration {
 
 		@Bean
 		@ConditionalOnMissingBean
-		public RetryLoadBalancerInterceptor ribbonInterceptor(
+		public RetryLoadBalancerInterceptor loadBalancerInterceptor(
 				LoadBalancerClient loadBalancerClient,
 				LoadBalancerRetryProperties properties,
 				LoadBalancerRequestFactory requestFactory,

spring-cloud-commons/src/main/java/org/springframework/cloud/client/loadbalancer/reactive/LoadBalancerBeanPostProcessorAutoConfiguration.java

@@ -18,11 +18,9 @@
 
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.beans.factory.config.BeanPostProcessor;
-import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.condition.AnyNestedCondition;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.cloud.client.loadbalancer.LoadBalanced;
 import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
 import org.springframework.context.ApplicationContext;
@@ -57,7 +55,6 @@ public LoadBalancerWebClientBuilderBeanPostProcessor loadBalancerWebClientBuilde
 	}
 
 	@Configuration(proxyBeanMethods = false)
-	@Conditional(OnNoRibbonDefaultCondition.class)
 	@ConditionalOnBean(ReactiveLoadBalancer.Factory.class)
 	protected static class ReactorDeferringLoadBalancerFilterConfig {
 
@@ -71,22 +68,6 @@ DeferringLoadBalancerExchangeFilterFunction<ReactorLoadBalancerExchangeFilterFun
 
 	}
 
-	@Configuration(proxyBeanMethods = false)
-	@ConditionalOnBean(LoadBalancerClient.class)
-	@AutoConfigureAfter(ReactorDeferringLoadBalancerFilterConfig.class)
-	@Deprecated
-	protected static class ReactiveLoadBalancerConfig {
-
-		@Bean
-		@ConditionalOnMissingBean
-		DeferringLoadBalancerExchangeFilterFunction<LoadBalancerExchangeFilterFunction> deferringLoadBalancerExchangeFilterFunction(
-				ObjectProvider<LoadBalancerExchangeFilterFunction> exchangeFilterFunctionProvider) {
-			return new DeferringLoadBalancerExchangeFilterFunction<>(
-					exchangeFilterFunctionProvider);
-		}
-
-	}
-
 	static final class OnAnyLoadBalancerImplementationPresentCondition
 			extends AnyNestedCondition {