Allow users to config comma-separated namespaces for ApolloConfigChangeListener

CHANGES.md

@@ -16,6 +16,6 @@ Apollo Java 2.1.0
 * [Apollo Client Support Spring Boot 3.0](https://github.com/apolloconfig/apollo-java/pull/4)
 * [apollo-client-config-data support spring boot 3.0](https://github.com/apolloconfig/apollo-java/pull/5)
 * [Add apollo-plugin-log4j2 module to support log4j2.xml integration](https://github.com/apolloconfig/apollo-java/pull/6)
-
+* [Allow users to config comma-separated namespaces for ApolloConfigChangeListener](https://github.com/apolloconfig/apollo-java/pull/11)
 ------------------
 All issues and pull requests are [here](https://github.com/apolloconfig/apollo-java/milestone/1?closed=1)

apollo-client/src/main/java/com/ctrip/framework/apollo/spring/annotation/ApolloAnnotationProcessor.java

@@ -27,11 +27,13 @@
 import com.ctrip.framework.apollo.spring.util.SpringInjector;
 import com.ctrip.framework.apollo.util.ConfigUtil;
 import com.google.common.base.Preconditions;
+import com.google.common.base.Splitter;
 import com.google.common.collect.Sets;
 import com.google.gson.Gson;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.lang.reflect.Type;
+import java.util.HashSet;
 import java.util.Set;
 import javax.annotation.Nullable;
 import org.slf4j.Logger;
@@ -54,6 +56,11 @@ public class ApolloAnnotationProcessor extends ApolloProcessor implements BeanFa
     EnvironmentAware {
 
   private static final Logger logger = LoggerFactory.getLogger(ApolloAnnotationProcessor.class);
+
+  private static final String NAMESPACE_DELIMITER = ",";
+
+  private static final Splitter NAMESPACE_SPLITTER = Splitter.on(NAMESPACE_DELIMITER)
+      .omitEmptyStrings().trimResults();
   private static final Gson GSON = new Gson();
 
   private final ConfigUtil configUtil;
@@ -128,9 +135,10 @@ private void processApolloConfigChangeListener(final Object bean, final Method m
         annotatedInterestedKeyPrefixes.length > 0 ? Sets.newHashSet(annotatedInterestedKeyPrefixes)
             : null;
 
-    for (String namespace : namespaces) {
-      final String resolvedNamespace = this.environment.resolveRequiredPlaceholders(namespace);
-      Config config = ConfigService.getConfig(resolvedNamespace);
+    Set<String> resolvedNamespaces = processResolveNamespaceValue(namespaces);
+
+    for (String namespace : resolvedNamespaces) {
+      Config config = ConfigService.getConfig(namespace);
 
       if (interestedKeys == null && interestedKeyPrefixes == null) {
         config.addChangeListener(configChangeListener);
@@ -140,6 +148,29 @@ private void processApolloConfigChangeListener(final Object bean, final Method m
     }
   }
 
+  /**
+   * Evaluate and resolve namespaces from env/properties.
+   * Split delimited namespaces
+   * @param namespaces
+   * @return resolved namespaces
+   */
+  private Set<String> processResolveNamespaceValue(String[] namespaces) {
+
+    Set<String> resolvedNamespaces = new HashSet<>();
+
+    for (String namespace : namespaces) {
+      final String resolvedNamespace = this.environment.resolveRequiredPlaceholders(namespace);
+
+      if (resolvedNamespace.contains(NAMESPACE_DELIMITER)) {
+        resolvedNamespaces.addAll(NAMESPACE_SPLITTER.splitToList(resolvedNamespace));
+      } else {
+        resolvedNamespaces.add(resolvedNamespace);
+      }
+    }
+
+    return resolvedNamespaces;
+  }
+
   private void processApolloJsonValue(Object bean, String beanName, Field field) {
     ApolloJsonValue apolloJsonValue = AnnotationUtils.getAnnotation(field, ApolloJsonValue.class);
     if (apolloJsonValue == null) {

apollo-client/src/main/java/com/ctrip/framework/apollo/spring/annotation/ApolloConfigChangeListener.java

@@ -40,6 +40,12 @@
  *     //handle change event
  * }
  * <br />
+ *  //The namespace could also be specified as a placeholder for a comma separated namespaces, e.g. ${app.allNamespaces}, where "all.allNamespaces" = "someNamespace,anotherNamespace,yetAnotherNamespace"
+ *  &#064;ApolloConfigChangeListener({"${app.allNamespaces}"})
+ *  private void onChange(ConfigChangeEvent changeEvent) {
+ *      //handle change event
+ *  }
+ *  <br />
  * //Listener on namespaces of "someNamespace" and "anotherNamespace", will only be notified when "someKey" or "anotherKey" is changed
  * &#064;ApolloConfigChangeListener(value = {"someNamespace","anotherNamespace"}, interestedKeys = {"someKey", "anotherKey"})
  * private void onChange(ConfigChangeEvent changeEvent) {

apollo-client/src/test/java/com/ctrip/framework/apollo/spring/JavaConfigAnnotationTest.java

@@ -63,8 +63,8 @@
 import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
-import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -94,6 +94,7 @@ public void tearDown() throws Exception {
     System.clearProperty(SystemPropertyKeyConstants.FROM_SYSTEM_YAML_NAMESPACE);
     System.clearProperty(SystemPropertyKeyConstants.FROM_NAMESPACE_APPLICATION_KEY);
     System.clearProperty(SystemPropertyKeyConstants.FROM_NAMESPACE_APPLICATION_KEY_YAML);
+    System.clearProperty(SystemPropertyKeyConstants.DELIMITED_NAMESPACES);
     System.clearProperty(ApolloClientSystemConsts.APOLLO_PROPERTY_NAMES_CACHE_ENABLE);
     super.tearDown();
   }
@@ -471,6 +472,57 @@ public void testApolloConfigChangeListenerResolveExpressionSimple() {
     verify(applicationConfig, times(3)).addChangeListener(any(ConfigChangeListener.class));
   }
 
+
+  /**
+   * resolve namespace's from comma separated namespaces
+   */
+  @Test
+  public void testApolloConfigChangeListenerWithCommaSeparatedNameSpaces() {
+
+    final String propValue = "app1,app2,app3";
+    System.setProperty(SystemPropertyKeyConstants.DELIMITED_NAMESPACES, propValue);
+
+    Config app1Config = mock(Config.class);
+    mockConfig("app1", app1Config);
+
+    Config app2Config = mock(Config.class);
+    mockConfig("app2", app2Config);
+
+    Config app3Config = mock(Config.class);
+    mockConfig("app3", app3Config);
+
+    getSimpleBean(TestApolloConfigChangeListenerWithCommaSeparatedNameSpaces.class);
+
+    verify(app1Config, times(1)).addChangeListener(any(ConfigChangeListener.class));
+    verify(app2Config, times(1)).addChangeListener(any(ConfigChangeListener.class));
+    verify(app3Config, times(1)).addChangeListener(any(ConfigChangeListener.class));
+  }
+
+  /**
+   * resolve namespace's from comma separated namespaces
+   */
+  @Test
+  public void testApolloConfigChangeListenerWithCommaSeparatedNameSpacesMergedWithOnesInValue() {
+
+    final String propValue = "app1,app2";
+    System.setProperty(SystemPropertyKeyConstants.DELIMITED_NAMESPACES, propValue);
+
+    Config app1Config = mock(Config.class);
+    mockConfig("app1", app1Config);
+
+    Config app2Config = mock(Config.class);
+    mockConfig("app2", app2Config);
+
+    Config appConfig = mock(Config.class);
+    mockConfig("app", appConfig);
+
+    getSimpleBean(TestApolloConfigChangeListenerWithCommaSeparatedNameSpacesMergedWithOnesInValue.class);
+
+    verify(app1Config, times(1)).addChangeListener(any(ConfigChangeListener.class));
+    verify(app2Config, times(1)).addChangeListener(any(ConfigChangeListener.class));
+    verify(appConfig, times(1)).addChangeListener(any(ConfigChangeListener.class));
+  }
+
   /**
    * resolve namespace's name from system property.
    */
@@ -597,6 +649,7 @@ private static class SystemPropertyKeyConstants {
     static final String FROM_SYSTEM_YAML_NAMESPACE = "from.system.yaml.namespace";
     static final String FROM_NAMESPACE_APPLICATION_KEY = "from.namespace.application.key";
     static final String FROM_NAMESPACE_APPLICATION_KEY_YAML = "from.namespace.application.key.yaml";
+    static final String DELIMITED_NAMESPACES = "delimited.namespaces";
   }
 
   @EnableApolloConfig
@@ -670,6 +723,24 @@ private void onChange(ConfigChangeEvent event) {
     }
   }
 
+  @Configuration
+  @EnableApolloConfig
+  static class TestApolloConfigChangeListenerWithCommaSeparatedNameSpaces {
+
+    @ApolloConfigChangeListener("${" + SystemPropertyKeyConstants.DELIMITED_NAMESPACES + "}")
+    private void onChange(ConfigChangeEvent changeEvent) {
+    }
+  }
+
+  @Configuration
+  @EnableApolloConfig
+  static class TestApolloConfigChangeListenerWithCommaSeparatedNameSpacesMergedWithOnesInValue {
+
+    @ApolloConfigChangeListener(value = {"app", "${" + SystemPropertyKeyConstants.DELIMITED_NAMESPACES + "}"})
+    private void onChange(ConfigChangeEvent changeEvent) {
+    }
+  }
+
   @Configuration
   @EnableApolloConfig
   static class TestApolloConfigChangeListenerResolveExpressionFromSystemPropertyConfiguration {