From da87ba6721a76a70da380eb879cf9212aec75981 Mon Sep 17 00:00:00 2001
From: Tom Briers <tbriers@telenet.be>
Date: Fri, 17 Jan 2020 08:05:43 +0100
Subject: [PATCH] Reworked so that multiple @RemoteApplicationScan annotations
 work together

fixes gh-214
---
 .../RemoteApplicationEventRegistrar.java      | 43 +++++++++++++++----
 .../RemoteApplicationEventScanTests.java      | 11 ++++-
 2 files changed, 44 insertions(+), 10 deletions(-)

diff --git a/spring-cloud-bus/src/main/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventRegistrar.java b/spring-cloud-bus/src/main/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventRegistrar.java
index fc201d9..ab968fc 100644
--- a/spring-cloud-bus/src/main/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventRegistrar.java
+++ b/spring-cloud-bus/src/main/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventRegistrar.java
@@ -16,6 +16,7 @@
 
 package org.springframework.cloud.bus.jackson;
 
+import java.util.Arrays;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
@@ -35,6 +36,10 @@ import org.springframework.util.StringUtils;
  */
 public class RemoteApplicationEventRegistrar implements ImportBeanDefinitionRegistrar {
 
+	private static final String PACKAGES_TO_SCAN = "packagesToScan";
+
+	private static final String BUS_JSON_CONVERTER = "busJsonConverter";
+
 	// patterned after Spring Integration IntegrationComponentScanRegistrar
 
 	@Override
@@ -65,15 +70,37 @@ public class RemoteApplicationEventRegistrar implements ImportBeanDefinitionRegi
 					ClassUtils.getPackageName(importingClassMetadata.getClassName()));
 		}
 
-		BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder
-				.genericBeanDefinition(BusJacksonMessageConverter.class);
-		beanDefinitionBuilder.addPropertyValue("packagesToScan",
-				basePackages.toArray(new String[basePackages.size()]));
-		AbstractBeanDefinition beanDefinition = beanDefinitionBuilder.getBeanDefinition();
+		if (!registry.containsBeanDefinition(BUS_JSON_CONVERTER)) {
+			BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder
+					.genericBeanDefinition(BusJacksonMessageConverter.class);
+			beanDefinitionBuilder.addPropertyValue(PACKAGES_TO_SCAN,
+					basePackages.toArray(new String[basePackages.size()]));
+			AbstractBeanDefinition beanDefinition = beanDefinitionBuilder
+					.getBeanDefinition();
 
-		BeanDefinitionHolder holder = new BeanDefinitionHolder(beanDefinition,
-				"busJsonConverter");
-		BeanDefinitionReaderUtils.registerBeanDefinition(holder, registry);
+			BeanDefinitionHolder holder = new BeanDefinitionHolder(beanDefinition,
+					BUS_JSON_CONVERTER);
+			BeanDefinitionReaderUtils.registerBeanDefinition(holder, registry);
+		}
+		else {
+			basePackages.addAll(getEarlierPackagesToScan(registry));
+			registry.getBeanDefinition(BUS_JSON_CONVERTER).getPropertyValues()
+					.addPropertyValue(PACKAGES_TO_SCAN,
+							basePackages.toArray(new String[basePackages.size()]));
+		}
+	}
+
+	private Set<String> getEarlierPackagesToScan(final BeanDefinitionRegistry registry) {
+		if (registry.containsBeanDefinition(BUS_JSON_CONVERTER)
+				&& registry.getBeanDefinition(BUS_JSON_CONVERTER).getPropertyValues()
+						.get(PACKAGES_TO_SCAN) != null) {
+			String[] earlierValues = (String[]) registry
+					.getBeanDefinition(BUS_JSON_CONVERTER).getPropertyValues()
+					.get(PACKAGES_TO_SCAN);
+			return new HashSet<>(Arrays.asList(earlierValues));
+		}
+
+		return new HashSet<>();
 	}
 
 }
diff --git a/spring-cloud-bus/src/test/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventScanTests.java b/spring-cloud-bus/src/test/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventScanTests.java
index 6981f26..c2bb235 100644
--- a/spring-cloud-bus/src/test/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventScanTests.java
+++ b/spring-cloud-bus/src/test/java/org/springframework/cloud/bus/jackson/RemoteApplicationEventScanTests.java
@@ -39,6 +39,7 @@ import org.springframework.cloud.bus.jackson.SubtypeModuleTests.AnotherRemoteApp
 import org.springframework.cloud.bus.jackson.SubtypeModuleTests.MyRemoteApplicationEvent;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
 import org.springframework.test.util.ReflectionTestUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -149,12 +150,18 @@ public class RemoteApplicationEventScanTests {
 	}
 
 	@Configuration(proxyBeanMethods = false)
-	@RemoteApplicationEventScan(
-			basePackages = { "com.acme", "test.foo.bar", "fizz.buzz" })
+	@Import(ExtraBasePackagesConfig.class)
+	@RemoteApplicationEventScan(basePackages = { "com.acme", "test.foo.bar" })
 	static class BasePackagesConfig {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	@RemoteApplicationEventScan(basePackages = { "fizz.buzz" })
+	static class ExtraBasePackagesConfig {
+
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	@RemoteApplicationEventScan(basePackageClasses = TestRemoteApplicationEvent.class)
 	static class BasePackageClassesConfig {