Revert changes in config server bootstrapper and use new PropertyResolver class (#328)

Co-authored-by: Ryan Baxter <[email protected]>

Author: Ryan Baxter

spring-cloud-zookeeper-discovery/src/main/java/org/springframework/cloud/zookeeper/discovery/configclient/ZookeeperConfigServerBootstrapper.java

@@ -17,13 +17,8 @@
 package org.springframework.cloud.zookeeper.discovery.configclient;
 
 import java.util.Collections;
-import java.util.List;
-import java.util.stream.Stream;
 
-import org.apache.commons.logging.Log;
-import org.apache.curator.RetryPolicy;
 import org.apache.curator.framework.CuratorFramework;
-import org.apache.curator.retry.ExponentialBackoffRetry;
 import org.apache.curator.x.discovery.ServiceDiscovery;
 import org.apache.curator.x.discovery.ServiceDiscoveryBuilder;
 import org.apache.curator.x.discovery.details.InstanceSerializer;
@@ -33,15 +28,13 @@
 import org.springframework.boot.BootstrapRegistry;
 import org.springframework.boot.BootstrapRegistryInitializer;
 import org.springframework.boot.context.properties.bind.BindHandler;
-import org.springframework.boot.context.properties.bind.Bindable;
 import org.springframework.boot.context.properties.bind.Binder;
-import org.springframework.cloud.client.ServiceInstance;
 import org.springframework.cloud.commons.util.InetUtils;
 import org.springframework.cloud.commons.util.InetUtilsProperties;
 import org.springframework.cloud.config.client.ConfigClientProperties;
+import org.springframework.cloud.config.client.ConfigServerConfigDataLocationResolver.PropertyResolver;
 import org.springframework.cloud.config.client.ConfigServerInstanceProvider;
 import org.springframework.cloud.zookeeper.CuratorFactory;
-import org.springframework.cloud.zookeeper.ZookeeperProperties;
 import org.springframework.cloud.zookeeper.discovery.ConditionalOnZookeeperDiscoveryEnabled;
 import org.springframework.cloud.zookeeper.discovery.ZookeeperDiscoveryClient;
 import org.springframework.cloud.zookeeper.discovery.ZookeeperDiscoveryProperties;
@@ -53,10 +46,16 @@
 
 public class ZookeeperConfigServerBootstrapper implements BootstrapRegistryInitializer {
 
-	private static boolean isEnabled(Binder binder) {
-		return binder.bind(ConfigClientProperties.CONFIG_DISCOVERY_ENABLED, Boolean.class).orElse(false) &&
-				binder.bind(ConditionalOnZookeeperDiscoveryEnabled.PROPERTY, Boolean.class).orElse(true) &&
-				binder.bind("spring.cloud.discovery.enabled", Boolean.class).orElse(true);
+	private static PropertyResolver getPropertyResolver(BootstrapContext context) {
+		return context.getOrElseSupply(PropertyResolver.class, () -> new PropertyResolver(
+				context.get(Binder.class), context.getOrElse(BindHandler.class, null)));
+	}
+
+	public static boolean isEnabled(BootstrapContext bootstrapContext) {
+		PropertyResolver propertyResolver = getPropertyResolver(bootstrapContext);
+		return propertyResolver.get(ConfigClientProperties.CONFIG_DISCOVERY_ENABLED, Boolean.class, false) &&
+				propertyResolver.get(ConditionalOnZookeeperDiscoveryEnabled.PROPERTY, Boolean.class, true) &&
+				propertyResolver.get("spring.cloud.discovery.enabled", Boolean.class, true);
 	}
 
 	@Override
@@ -67,27 +66,28 @@ public void initialize(BootstrapRegistry registry) {
 				ClassUtils.isPresent("org.springframework.cloud.bootstrap.marker.Marker", null)) {
 			return;
 		}
+
 		// create curator
-		CuratorFactory.registerCurator(registry, null, true, bootstrapContext -> isEnabled(bootstrapContext.get(Binder.class)));
+		CuratorFactory.registerCurator(registry, null, true, ZookeeperConfigServerBootstrapper::isEnabled);
 
 		// create discovery
 		registry.registerIfAbsent(ZookeeperDiscoveryProperties.class, context -> {
-			Binder binder = context.get(Binder.class);
-			if (!isEnabled(binder)) {
+			if (!isEnabled(context)) {
 				return null;
 			}
-			return binder.bind(ZookeeperDiscoveryProperties.PREFIX, Bindable
-							.of(ZookeeperDiscoveryProperties.class), getBindHandler(context))
-					.orElseGet(() -> new ZookeeperDiscoveryProperties(new InetUtils(new InetUtilsProperties())));
+			PropertyResolver propertyResolver = getPropertyResolver(context);
+			return propertyResolver.resolveConfigurationProperties(ZookeeperDiscoveryProperties.PREFIX,
+					ZookeeperDiscoveryProperties.class,
+					() -> new ZookeeperDiscoveryProperties(new InetUtils(new InetUtilsProperties())));
 		});
 		registry.registerIfAbsent(InstanceSerializer.class, context -> {
-			if (!isEnabled(context.get(Binder.class))) {
+			if (!isEnabled(context)) {
 				return null;
 			}
 			return new JsonInstanceSerializer<>(ZookeeperInstance.class);
 		});
 		registry.registerIfAbsent(ServiceDiscoveryCustomizer.class, context -> {
-			if (!isEnabled(context.get(Binder.class))) {
+			if (!isEnabled(context)) {
 				return null;
 			}
 			CuratorFramework curator = context.get(CuratorFramework.class);
@@ -96,30 +96,31 @@ public void initialize(BootstrapRegistry registry) {
 			return new DefaultServiceDiscoveryCustomizer(curator, properties, serializer);
 		});
 		registry.registerIfAbsent(ServiceDiscovery.class, context -> {
-			if (!isEnabled(context.get(Binder.class))) {
+			if (!isEnabled(context)) {
 				return null;
 			}
 			ServiceDiscoveryCustomizer customizer = context.get(ServiceDiscoveryCustomizer.class);
 			return customizer.customize(ServiceDiscoveryBuilder.builder(ZookeeperInstance.class));
 		});
 		registry.registerIfAbsent(ZookeeperDiscoveryClient.class, context -> {
-			Binder binder = context.get(Binder.class);
-			if (!isEnabled(binder)) {
+			if (!isEnabled(context)) {
 				return null;
 			}
+			PropertyResolver propertyResolver = getPropertyResolver(context);
 			ServiceDiscovery<ZookeeperInstance> serviceDiscovery = context.get(ServiceDiscovery.class);
-			ZookeeperDependencies dependencies = binder.bind(ZookeeperDependencies.PREFIX, Bindable
-							.of(ZookeeperDependencies.class), getBindHandler(context))
-					.orElseGet(ZookeeperDependencies::new);
+			ZookeeperDependencies dependencies = propertyResolver.resolveConfigurationProperties(ZookeeperDependencies.PREFIX, ZookeeperDependencies.class, ZookeeperDependencies::new);
 			ZookeeperDiscoveryProperties discoveryProperties = context.get(ZookeeperDiscoveryProperties.class);
 
 			return new ZookeeperDiscoveryClient(serviceDiscovery, dependencies, discoveryProperties);
 		});
 
 		// create instance provider
-		// We need to pass the lambda here so we do not create a new instance of ConfigServerInstanceProvider.Function
-		// which would result in a ClassNotFoundException when Spring Cloud Config is not on the classpath
-		registry.registerIfAbsent(ConfigServerInstanceProvider.Function.class, ZookeeperFunction::create);
+		registry.registerIfAbsent(ConfigServerInstanceProvider.Function.class, context -> {
+			if (!isEnabled(context)) {
+				return (id) -> Collections.emptyList();
+			}
+			return context.get(ZookeeperDiscoveryClient.class)::getInstances;
+		});
 
 		// promote beans to context
 		registry.addCloseListener(event -> {
@@ -130,68 +131,4 @@ public void initialize(BootstrapRegistry registry) {
 			}
 		});
 	}
-
-	private BindHandler getBindHandler(org.springframework.boot.BootstrapContext context) {
-		return context.getOrElse(BindHandler.class, null);
-	}
-
-	/*
-	 * This Function is executed when loading config data.  Because of this we cannot rely on the
-	 * BootstrapContext because Boot has not finished loading all the configuration data so if we
-	 * ask the BootstrapContext for configuration data it will not have it.  The apply method in this function
-	 * is passed the Binder and BindHandler from the config data context which has the configuration properties that
-	 * have been loaded so far in the config data process.
-	 *
-	 * We will create many of the same beans in this function as we do above in the initializer above.  We do both
-	 * to maintain compatibility since we are promoting those beans to the main application context.
-	 */
-	static final class ZookeeperFunction implements ConfigServerInstanceProvider.Function {
-
-		private final BootstrapContext context;
-
-		private ZookeeperFunction(BootstrapContext context) {
-			this.context = context;
-		}
-
-		static ZookeeperFunction create(BootstrapContext context) {
-			return new ZookeeperFunction(context);
-		}
-
-		@Override
-		public List<ServiceInstance> apply(String serviceId) {
-			return apply(serviceId, null, null, null);
-		}
-
-		@Override
-		public List<ServiceInstance> apply(String serviceId, Binder binder, BindHandler bindHandler, Log log) {
-			if (binder == null || !isEnabled(binder)) {
-				return Collections.emptyList();
-			}
-
-			ZookeeperProperties properties = context.getOrElse(ZookeeperProperties.class, binder.bind(ZookeeperProperties.PREFIX, Bindable.of(ZookeeperProperties.class))
-					.orElse(new ZookeeperProperties()));
-			RetryPolicy retryPolicy = context.getOrElse(RetryPolicy.class, new ExponentialBackoffRetry(properties.getBaseSleepTimeMs(), properties.getMaxRetries(),
-					properties.getMaxSleepMs()));
-			try {
-				CuratorFramework curatorFramework = context.getOrElse(CuratorFramework.class, CuratorFactory.curatorFramework(properties, retryPolicy, Stream::of,
-						() -> null, () -> null));
-				InstanceSerializer<ZookeeperInstance> serializer = context.getOrElse(InstanceSerializer.class, new JsonInstanceSerializer<>(ZookeeperInstance.class));
-				ZookeeperDiscoveryProperties discoveryProperties = context.getOrElse(ZookeeperDiscoveryProperties.class, binder.bind(ZookeeperDiscoveryProperties.PREFIX, Bindable
-								.of(ZookeeperDiscoveryProperties.class), bindHandler)
-						.orElseGet(() -> new ZookeeperDiscoveryProperties(new InetUtils(new InetUtilsProperties()))));
-				ServiceDiscoveryCustomizer customizer = context.getOrElse(ServiceDiscoveryCustomizer.class, new DefaultServiceDiscoveryCustomizer(curatorFramework, discoveryProperties, serializer));
-				ServiceDiscovery<ZookeeperInstance> serviceDiscovery = customizer.customize(ServiceDiscoveryBuilder.builder(ZookeeperInstance.class));
-				ZookeeperDependencies dependencies = context.getOrElse(ZookeeperDependencies.class, binder.bind(ZookeeperDependencies.PREFIX, Bindable
-								.of(ZookeeperDependencies.class), bindHandler)
-						.orElseGet(ZookeeperDependencies::new));
-				return new ZookeeperDiscoveryClient(serviceDiscovery, dependencies, discoveryProperties).getInstances(serviceId);
-			}
-			catch (Exception e) {
-				log.warn("Error fetching config server instance from Zookeeper", e);
-				return Collections.emptyList();
-			}
-
-		}
-	}
-
 }