Dubbo Guide

whatsmars-dubbo/README.md

@@ -87,7 +87,16 @@ RpcContext 的状态都会变化。比如：A 调 B，B 再调 C，则 B 机器
 RpcContext.getContext().setAttachment("index", "1");
 xxxService.xxx(); // 远程调用
 ```
-- 本地伪装：<dubbo:service interface="com.foo.BarService" mock="com.foo.BarServiceMock" />
+- 本地伪装，通常用于降级：<dubbo:service interface="com.foo.BarService" mock="com.foo.BarServiceMock" />
+<br>如果服务的消费方经常需要 try-catch 捕获异常，请考虑改为 Mock 实现，并在 Mock 实现中 return null。
+如果只是想简单的忽略异常，用mock="return null"即可
+- 服务降级，向注册中心写入动态配置覆盖规则：
+```java
+RegistryFactory registryFactory = ExtensionLoader.getExtensionLoader(RegistryFactory.class).getAdaptiveExtension();
+Registry registry = registryFactory.getRegistry(URL.valueOf("zookeeper://10.20.153.10:2181"));
+// mock=force:return+null mock=fail:return+null
+registry.register(URL.valueOf("override://0.0.0.0/com.foo.BarService?category=configurators&dynamic=false&application=foo&mock=fail:return+null"));
+```
 - 延迟暴露
 ```xml
 <!-- 延迟 5 秒暴露服务 -->

whatsmars-dubbo/whatsmars-dubbo-consumer/src/main/resources/META-INF/spring/dubbo-demo-consumer.xml

@@ -12,12 +12,13 @@
 	<!--&lt;!&ndash; 使用zookeeper注册中心暴露服务地址 &ndash;&gt;-->
 	<!--<dubbo:registry address="zookeeper://127.0.0.1:2181" />-->
 
-	<dubbo:reference id="demoService" interface="org.hongxi.whatsmars.dubbo.demo.api.DemoService" />
+	<dubbo:reference id="demoService" interface="org.hongxi.whatsmars.dubbo.demo.api.DemoService" mock="return null" />
 
 	<!-- url="hessian://127.0.0.1:8080/org.hongxi.whatsmars.dubbo.demo.api.DemoService" -->
 	<dubbo:reference id="demoService2" interface="org.hongxi.whatsmars.dubbo.demo.api.DemoService"
 					 url="hessian://127.0.0.1:8080" />
 
+	<!--protocol默认dubbo，可指定，如果provider没有以该protocol发布，consumer启动会报 No provider-->
 	<dubbo:reference id="demoService3" interface="org.hongxi.whatsmars.dubbo.demo.api.DemoService" protocol="hessian" />
 
 	<dubbo:reference id="demoService4" group="new" interface="org.hongxi.whatsmars.dubbo.demo.api.DemoService" />

whatsmars-dubbo/whatsmars-dubbo-provider/src/main/resources/META-INF/spring/dubbo-demo-provider.xml

@@ -14,7 +14,7 @@
 	<!--<dubbo:application name="whatsmars_provider" />-->
 	<!--&lt;!&ndash; 使用zookeeper注册中心暴露服务地址 &ndash;&gt;-->
 	<!--<dubbo:registry address="zookeeper://127.0.0.1:2181" />-->
-    <!-- 多协议配置 -->
+    <!-- 多协议配置，一种协议只能对应一种序列化方式，建议用hessian2序列化（也是官方推荐，处于稳定性和性能的折中考虑）-->
     <dubbo:protocol name="dubbo" port="20880" server="netty4" serialization="fst" />
 	<dubbo:protocol name="hessian" port="8080" server="jetty" />