support configuring namespaces as placeholders

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

@@ -3,25 +3,73 @@
 import com.ctrip.framework.apollo.Config;
 import com.ctrip.framework.apollo.ConfigChangeListener;
 import com.ctrip.framework.apollo.ConfigService;
+import com.ctrip.framework.apollo.build.ApolloInjector;
 import com.ctrip.framework.apollo.model.ConfigChangeEvent;
+import com.ctrip.framework.apollo.spring.property.PlaceholderHelper;
+import com.ctrip.framework.apollo.spring.property.SpringValue;
+import com.ctrip.framework.apollo.spring.property.SpringValueRegistry;
+import com.ctrip.framework.apollo.spring.util.SpringInjector;
+import com.ctrip.framework.apollo.util.ConfigUtil;
 import com.google.common.base.Preconditions;
+import com.google.gson.Gson;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
+import java.lang.reflect.Type;
 import java.util.Set;
 
 import com.google.common.collect.Sets;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.config.ConfigurableBeanFactory;
+import org.springframework.context.EnvironmentAware;
 import org.springframework.core.annotation.AnnotationUtils;
+import org.springframework.core.env.Environment;
 import org.springframework.util.ReflectionUtils;
 
 /**
  * Apollo Annotation Processor for Spring Application
  *
  * @author Jason Song([email protected])
  */
-public class ApolloAnnotationProcessor extends ApolloProcessor {
+public class ApolloAnnotationProcessor extends ApolloProcessor implements BeanFactoryAware,
+    EnvironmentAware {
+
+  private static final Logger logger = LoggerFactory.getLogger(ApolloAnnotationProcessor.class);
+  private static final Gson GSON = new Gson();
+
+  private final ConfigUtil configUtil;
+  private final PlaceholderHelper placeholderHelper;
+  private final SpringValueRegistry springValueRegistry;
+
+  /**
+   * resolve the expression.
+   */
+  private ConfigurableBeanFactory configurableBeanFactory;
+
+  private Environment environment;
+
+  public ApolloAnnotationProcessor() {
+    configUtil = ApolloInjector.getInstance(ConfigUtil.class);
+    placeholderHelper = SpringInjector.getInstance(PlaceholderHelper.class);
+    springValueRegistry = SpringInjector.getInstance(SpringValueRegistry.class);
+  }
 
   @Override
   protected void processField(Object bean, String beanName, Field field) {
+    this.processApolloConfig(bean, field);
+    this.processApolloJsonValue(bean, beanName, field);
+  }
+
+  @Override
+  protected void processMethod(final Object bean, String beanName, final Method method) {
+    this.processApolloConfigChangeListener(bean, method);
+    this.processApolloJsonValue(bean, beanName, method);
+  }
+
+  private void processApolloConfig(Object bean, Field field) {
     ApolloConfig annotation = AnnotationUtils.getAnnotation(field, ApolloConfig.class);
     if (annotation == null) {
       return;
@@ -30,15 +78,15 @@ protected void processField(Object bean, String beanName, Field field) {
     Preconditions.checkArgument(Config.class.isAssignableFrom(field.getType()),
         "Invalid type: %s for field: %s, should be Config", field.getType(), field);
 
-    String namespace = annotation.value();
-    Config config = ConfigService.getConfig(namespace);
+    final String namespace = annotation.value();
+    final String resolvedNamespace = this.environment.resolveRequiredPlaceholders(namespace);
+    Config config = ConfigService.getConfig(resolvedNamespace);
 
     ReflectionUtils.makeAccessible(field);
     ReflectionUtils.setField(field, bean, config);
   }
 
-  @Override
-  protected void processMethod(final Object bean, String beanName, final Method method) {
+  private void processApolloConfigChangeListener(final Object bean, final Method method) {
     ApolloConfigChangeListener annotation = AnnotationUtils
         .findAnnotation(method, ApolloConfigChangeListener.class);
     if (annotation == null) {
@@ -63,11 +111,15 @@ public void onChange(ConfigChangeEvent changeEvent) {
       }
     };
 
-    Set<String> interestedKeys = annotatedInterestedKeys.length > 0 ? Sets.newHashSet(annotatedInterestedKeys) : null;
-    Set<String> interestedKeyPrefixes = annotatedInterestedKeyPrefixes.length > 0 ? Sets.newHashSet(annotatedInterestedKeyPrefixes) : null;
+    Set<String> interestedKeys =
+        annotatedInterestedKeys.length > 0 ? Sets.newHashSet(annotatedInterestedKeys) : null;
+    Set<String> interestedKeyPrefixes =
+        annotatedInterestedKeyPrefixes.length > 0 ? Sets.newHashSet(annotatedInterestedKeyPrefixes)
+            : null;
 
     for (String namespace : namespaces) {
-      Config config = ConfigService.getConfig(namespace);
+      final String resolvedNamespace = this.environment.resolveRequiredPlaceholders(namespace);
+      Config config = ConfigService.getConfig(resolvedNamespace);
 
       if (interestedKeys == null && interestedKeyPrefixes == null) {
         config.addChangeListener(configChangeListener);
@@ -76,4 +128,90 @@ public void onChange(ConfigChangeEvent changeEvent) {
       }
     }
   }
+
+
+  private void processApolloJsonValue(Object bean, String beanName, Field field) {
+    ApolloJsonValue apolloJsonValue = AnnotationUtils.getAnnotation(field, ApolloJsonValue.class);
+    if (apolloJsonValue == null) {
+      return;
+    }
+    String placeholder = apolloJsonValue.value();
+    Object propertyValue = placeholderHelper
+        .resolvePropertyValue(this.configurableBeanFactory, beanName, placeholder);
+
+    // propertyValue will never be null, as @ApolloJsonValue will not allow that
+    if (!(propertyValue instanceof String)) {
+      return;
+    }
+
+    boolean accessible = field.isAccessible();
+    field.setAccessible(true);
+    ReflectionUtils
+        .setField(field, bean, parseJsonValue((String) propertyValue, field.getGenericType()));
+    field.setAccessible(accessible);
+
+    if (configUtil.isAutoUpdateInjectedSpringPropertiesEnabled()) {
+      Set<String> keys = placeholderHelper.extractPlaceholderKeys(placeholder);
+      for (String key : keys) {
+        SpringValue springValue = new SpringValue(key, placeholder, bean, beanName, field, true);
+        springValueRegistry.register(this.configurableBeanFactory, key, springValue);
+        logger.debug("Monitoring {}", springValue);
+      }
+    }
+  }
+
+  private void processApolloJsonValue(Object bean, String beanName, Method method) {
+    ApolloJsonValue apolloJsonValue = AnnotationUtils.getAnnotation(method, ApolloJsonValue.class);
+    if (apolloJsonValue == null) {
+      return;
+    }
+    String placeHolder = apolloJsonValue.value();
+
+    Object propertyValue = placeholderHelper
+        .resolvePropertyValue(this.configurableBeanFactory, beanName, placeHolder);
+
+    // propertyValue will never be null, as @ApolloJsonValue will not allow that
+    if (!(propertyValue instanceof String)) {
+      return;
+    }
+
+    Type[] types = method.getGenericParameterTypes();
+    Preconditions.checkArgument(types.length == 1,
+        "Ignore @Value setter {}.{}, expecting 1 parameter, actual {} parameters",
+        bean.getClass().getName(), method.getName(), method.getParameterTypes().length);
+
+    boolean accessible = method.isAccessible();
+    method.setAccessible(true);
+    ReflectionUtils.invokeMethod(method, bean, parseJsonValue((String) propertyValue, types[0]));
+    method.setAccessible(accessible);
+
+    if (configUtil.isAutoUpdateInjectedSpringPropertiesEnabled()) {
+      Set<String> keys = placeholderHelper.extractPlaceholderKeys(placeHolder);
+      for (String key : keys) {
+        SpringValue springValue = new SpringValue(key, apolloJsonValue.value(), bean, beanName,
+            method, true);
+        springValueRegistry.register(this.configurableBeanFactory, key, springValue);
+        logger.debug("Monitoring {}", springValue);
+      }
+    }
+  }
+
+  private Object parseJsonValue(String json, Type targetType) {
+    try {
+      return GSON.fromJson(json, targetType);
+    } catch (Throwable ex) {
+      logger.error("Parsing json '{}' to type {} failed!", json, targetType, ex);
+      throw ex;
+    }
+  }
+
+  @Override
+  public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
+    this.configurableBeanFactory = (ConfigurableBeanFactory) beanFactory;
+  }
+
+  @Override
+  public void setEnvironment(Environment environment) {
+    this.environment = environment;
+  }
 }

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

@@ -18,6 +18,15 @@
  * private Config config;
  * </pre>
  *
+ * <p>Usage example with placeholder:</p>
+ * <pre class="code">
+ * // The namespace could also be specified as a placeholder, e.g. ${redis.namespace:xxx},
+ * // which will use the value of the key "redis.namespace" or "xxx" if this key is not configured.
+ * &#064;ApolloConfig("${redis.namespace:xxx}")
+ * private Config config;
+ * </pre>
+ *
+ *
  * @author Jason Song([email protected])
  */
 @Retention(RetentionPolicy.RUNTIME)

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

@@ -18,6 +18,12 @@
  *     //handle change event
  * }
  * <br />
+ * //The namespace could also be specified as a placeholder, e.g. ${redis.namespace:xxx}, which will use the value of the key "redis.namespace" or "xxx" if this key is not configured.
+ * &#064;ApolloConfigChangeListener({"${redis.namespace:xxx}"})
+ * 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/main/java/com/ctrip/framework/apollo/spring/annotation/ApolloConfigRegistrar.java

@@ -3,18 +3,26 @@
 import com.ctrip.framework.apollo.spring.spi.ApolloConfigRegistrarHelper;
 import com.ctrip.framework.foundation.internals.ServiceBootstrap;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
+import org.springframework.context.EnvironmentAware;
 import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
+import org.springframework.core.env.Environment;
 import org.springframework.core.type.AnnotationMetadata;
 
 /**
  * @author Jason Song([email protected])
  */
-public class ApolloConfigRegistrar implements ImportBeanDefinitionRegistrar {
+public class ApolloConfigRegistrar implements ImportBeanDefinitionRegistrar, EnvironmentAware {
 
-  private ApolloConfigRegistrarHelper helper = ServiceBootstrap.loadPrimary(ApolloConfigRegistrarHelper.class);
+  private final ApolloConfigRegistrarHelper helper = ServiceBootstrap.loadPrimary(ApolloConfigRegistrarHelper.class);
 
   @Override
   public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
     helper.registerBeanDefinitions(importingClassMetadata, registry);
   }
+
+  @Override
+  public void setEnvironment(Environment environment) {
+    this.helper.setEnvironment(environment);
+  }
+
 }