refactor(springboot openfeign): Use BeanPostProcessor to modify the original Targeter beans instead of override them.

Signed-off-by: lony2003 <zhangke200377@outlook.com>

Author: lony2003

dapr-spring/dapr-spring-openfeign/src/main/java/io/dapr/spring/openfeign/autoconfigure/DaprFeignClientAutoConfiguration.java

@@ -15,27 +15,23 @@
 
 import io.dapr.client.DaprClient;
 import io.dapr.feign.DaprInvokeFeignClient;
-import io.dapr.spring.openfeign.targeter.DaprClientTargeter;
+import io.dapr.spring.openfeign.targeter.DaprClientTargeterBeanPostProcessor;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.cloud.openfeign.FeignAutoConfiguration;
-import org.springframework.cloud.openfeign.Targeter;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
 
 @Configuration(proxyBeanMethods = false)
 @EnableConfigurationProperties(DaprFeignClientProperties.class)
 @ConditionalOnProperty(name = "dapr.feign.enabled", matchIfMissing = true)
 @ConditionalOnClass(FeignAutoConfiguration.class)
+@Import(DaprClientTargeterBeanPostProcessor.class)
 public class DaprFeignClientAutoConfiguration {
 
-  @Bean
-  public Targeter targeter(DaprInvokeFeignClient daprInvokeFeignClient) {
-    return new DaprClientTargeter(daprInvokeFeignClient);
-  }
-
   @SuppressWarnings("checkstyle:MissingJavadocMethod")
   @Bean
   @ConditionalOnMissingBean

dapr-spring/dapr-spring-openfeign/src/main/java/io/dapr/spring/openfeign/targeter/DaprClientTargeter.java

@@ -27,14 +27,28 @@
 public class DaprClientTargeter implements Targeter {
 
   private final DaprInvokeFeignClient daprInvokeFeignClient;
+  private final Targeter targeter;
 
-  public DaprClientTargeter(DaprInvokeFeignClient daprInvokeFeignClient) {
+  public DaprClientTargeter(DaprInvokeFeignClient daprInvokeFeignClient, Targeter targeter) {
     this.daprInvokeFeignClient = daprInvokeFeignClient;
+    this.targeter = targeter;
   }
 
   @Override
   public <T> T target(FeignClientFactoryBean factory, Feign.Builder feign, FeignClientFactory context,
                       Target.HardCodedTarget<T> target) {
+    Class<T> classOfT = target.type();
+    UseDaprClient useDaprClient = classOfT.getAnnotation(UseDaprClient.class);
+
+    if (useDaprClient == null) {
+      return targeter.target(
+          factory,
+          feign,
+          context,
+          target
+      );
+    }
+
     Class<Feign.Builder> builderClass = Feign.Builder.class;
 
     Client defaultClient = null;
@@ -49,12 +63,7 @@ public <T> T target(FeignClientFactoryBean factory, Feign.Builder feign, FeignCl
       throw new RuntimeException(e);
     }
 
-    Class<T> classOfT = target.type();
-    UseDaprClient useDaprClient = classOfT.getAnnotation(UseDaprClient.class);
-
-    if (useDaprClient != null) {
-      feign.client(daprInvokeFeignClient);
-    }
+    feign.client(daprInvokeFeignClient);
 
     T targetInstance = feign.target(target);
 

dapr-spring/dapr-spring-openfeign/src/main/java/io/dapr/spring/openfeign/targeter/DaprClientTargeterBeanPostProcessor.java

@@ -0,0 +1,27 @@
+package io.dapr.spring.openfeign.targeter;
+
+import io.dapr.feign.DaprInvokeFeignClient;
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.config.BeanPostProcessor;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
+import org.springframework.cloud.openfeign.Targeter;
+import org.springframework.stereotype.Component;
+
+@Component
+@ConditionalOnBean(Targeter.class)
+public class DaprClientTargeterBeanPostProcessor implements BeanPostProcessor {
+
+  private final DaprInvokeFeignClient daprInvokeFeignClient;
+
+  public DaprClientTargeterBeanPostProcessor(DaprInvokeFeignClient daprInvokeFeignClient) {
+    this.daprInvokeFeignClient = daprInvokeFeignClient;
+  }
+
+  @Override
+  public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
+    if (bean instanceof Targeter) {
+      return new DaprClientTargeter(daprInvokeFeignClient, (Targeter) bean);
+    }
+    return bean;
+  }
+}