增加 Hystrix 入门示例

Author: YunaiV

labx-23/labx-23-scn-hystrix-demo01/src/main/java/cn/iocoder/springcloud/labx23/hystrixdemo/controller/CollapserDemoController.java

@@ -0,0 +1,34 @@
+package cn.iocoder.springcloud.labx23.hystrixdemo.controller;
+
+import cn.iocoder.springcloud.labx23.hystrixdemo.service.CollapserDemoService;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+
+@RestController
+@RequestMapping("/collapser-demo")
+public class CollapserDemoController {
+
+    private Logger logger = LoggerFactory.getLogger(CollapserDemoController.class);
+
+    @Autowired
+    private CollapserDemoService collapserDemoService;
+
+    @GetMapping("/test")
+    public void test() throws ExecutionException, InterruptedException {
+        logger.info("[test][准备获取用户信息]");
+        Future<String> user01 = collapserDemoService.getUserFuture(1);
+        Future<String> user02 = collapserDemoService.getUserFuture(2);
+        logger.info("[test][提交获取用户信息]");
+
+        logger.info("[test][user({}) 的结果为({})]", 1, user01.get());
+        logger.info("[test][user({}) 的结果为({})]", 2, user02.get());
+    }
+
+}

labx-23/labx-23-scn-hystrix-demo01/src/main/java/cn/iocoder/springcloud/labx23/hystrixdemo/service/CollapserDemoService.java

@@ -0,0 +1,44 @@
+package cn.iocoder.springcloud.labx23.hystrixdemo.service;
+
+import com.netflix.hystrix.contrib.javanica.annotation.HystrixCollapser;
+import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
+import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty;
+import org.apache.commons.lang.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import org.springframework.web.client.RestTemplate;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.Future;
+
+@Service
+public class CollapserDemoService {
+
+    private Logger logger = LoggerFactory.getLogger(CollapserDemoService.class);
+
+    @Autowired
+    private RestTemplate restTemplate;
+
+    @HystrixCollapser(
+            batchMethod = "getUsers",
+            collapserProperties = {
+                    @HystrixProperty(name = "timerDelayInMilliseconds", value = "10000") // 演示，所以设置的时间较长
+            }
+    )
+    public Future<String> getUserFuture(Integer id) {
+        throw new RuntimeException("This method body should not be executed");
+    }
+
+    @HystrixCommand
+    public List<String> getUsers(List<Integer> ids) {
+        logger.info("[getUsers][准备调用 user-service 获取多个用户({})详情]", ids);
+        String[] users = restTemplate.getForEntity("http://127.0.0.1:18080/user/batch_get?ids=" + StringUtils.join(ids, ',')
+                , String[].class).getBody();
+        return users == null || users.length == 0 ? Collections.emptyList() : Arrays.asList(users);
+    }
+
+}

labx-23/labx-23-user-service/pom.xml

@@ -12,7 +12,8 @@
     <artifactId>labx-23-user-service</artifactId>
 
     <properties>
-        <java.version>1.8</java.version>
+        <maven.compiler.target>1.8</maven.compiler.target>
+        <maven.compiler.source>1.8</maven.compiler.source>
         <spring.boot.version>2.2.4.RELEASE</spring.boot.version>
         <spring.cloud.version>Hoxton.SR1</spring.cloud.version>
     </properties>

labx-23/labx-23-user-service/src/main/java/cn/iocoder/springcloud/labx23/userservice/UserServiceApplication.java

@@ -7,6 +7,9 @@
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 
+import java.util.List;
+import java.util.stream.Collectors;
+
 @SpringBootApplication
 public class UserServiceApplication {
 
@@ -19,6 +22,11 @@ public String get(@RequestParam("id") Integer id) {
             return "User:" + id;
         }
 
+        @GetMapping("/batch_get")
+        public List<String> batchGet(@RequestParam("ids") List<Integer> ids) {
+            return ids.stream().map(id -> "User:" + id).collect(Collectors.toList());
+        }
+
     }
 
     public static void main(String[] args) {