Nacos通过OpenFeign实现负载均衡远程调用

borrow-service/pom.xml

@@ -18,6 +18,10 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <dependencies>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-starter-openfeign</artifactId>
+        </dependency>
         <dependency>
             <groupId>com.alibaba.cloud</groupId>
             <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>

borrow-service/src/main/java/com/test/BorrowApplication.java

@@ -3,6 +3,7 @@ package com.test;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.autoconfigure.security.oauth2.client.EnableOAuth2Sso;
+import org.springframework.cloud.openfeign.EnableFeignClients;
 import org.springframework.security.oauth2.config.annotation.web.configuration.EnableResourceServer;
 
 /**
@@ -13,6 +14,7 @@ import org.springframework.security.oauth2.config.annotation.web.configuration.E
  * @Create 2023/8/14 16:25
  */
 @EnableResourceServer
+@EnableFeignClients
 @SpringBootApplication
 public class BorrowApplication {
     public static void main(String[] args) {

borrow-service/src/main/java/com/test/config/WebConfiguration.java

@@ -1,30 +0,0 @@
-package com.test.config;
-
-import org.springframework.cloud.client.loadbalancer.LoadBalanced;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.security.oauth2.client.OAuth2ClientContext;
-import org.springframework.security.oauth2.client.OAuth2RestTemplate;
-import org.springframework.security.oauth2.client.token.grant.client.ClientCredentialsResourceDetails;
-
-import javax.annotation.Resource;
-
-/**
- * ClassName: ma
- * Package: com.test.config
- *
- * @author yovinchen
- * @Create 2023/8/21 10:52
- */
-@Configuration
-public class WebConfiguration {
-
-    @Resource
-    OAuth2ClientContext context;
-
-    @Bean
-    @LoadBalanced
-    public OAuth2RestTemplate restTemplate(){
-        return new OAuth2RestTemplate(new ClientCredentialsResourceDetails(), context);
-    }
-}

borrow-service/src/main/java/com/test/service/client/BookClient.java

@@ -0,0 +1,20 @@
+package com.test.service.client;
+
+import com.test.entity.Book;
+import org.springframework.cloud.openfeign.FeignClient;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+/**
+ * ClassName: BookClient
+ * Package: com.test.service.client
+ *
+ * @author yovinchen
+ * @Create 2023/8/21 20:29
+ */
+@FeignClient("bookservice")
+public interface BookClient {
+
+    @RequestMapping("/book/{bid}")
+    Book getBookById(@PathVariable("bid") int bid);
+}

borrow-service/src/main/java/com/test/service/client/UserClient.java

@@ -0,0 +1,20 @@
+package com.test.service.client;
+
+import com.test.entity.User;
+import org.springframework.cloud.openfeign.FeignClient;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+/**
+ * ClassName: UserClient
+ * Package: com.test.service.client
+ *
+ * @author yovinchen
+ * @Create 2023/8/21 20:29
+ */
+@FeignClient("userservice")
+public interface UserClient {
+
+    @RequestMapping("/user/{uid}")
+    User getUserById(@PathVariable("uid") int uid);
+}

borrow-service/src/main/java/com/test/service/impl/BorrowServiceImpl.java

@@ -8,6 +8,8 @@ import com.test.entity.User;
 import com.test.entity.UserBorrowDetail;
 import com.test.mapper.BorrowMapper;
 import com.test.service.BorrowService;
+import com.test.service.client.BookClient;
+import com.test.service.client.UserClient;
 import org.springframework.security.oauth2.client.OAuth2RestTemplate;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.RestTemplate;
@@ -30,16 +32,21 @@ public class BorrowServiceImpl implements BorrowService {
     BorrowMapper mapper;
 
     @Resource
-    OAuth2RestTemplate template;
+    BookClient bookClient;
+
+    @Resource
+    UserClient userClient;
 
     @Override
     public UserBorrowDetail getUserBorrowDetailByUid(int uid) {
         List<Borrow> borrow = mapper.getBorrowsByUid(uid);
         //这里通过调用getForObject来请求其他服务，并将结果自动进行封装
         //获取User信息
-        User user = template.getForObject("http://userservice/user/" + uid, User.class);
+        User user = userClient.getUserById(uid);
         //获取每一本书的详细信息
-        List<Book> bookList = borrow.stream().map(b -> template.getForObject("http://bookservice/book/" + b.getBid(), Book.class)).collect(Collectors.toList());
+        List<Book> bookList = borrow.stream()
+                .map(b -> bookClient.getBookById(b.getBid()))
+                .collect(Collectors.toList());
         return new UserBorrowDetail(user, bookList);
     }
 }

borrow-service/src/main/resources/application.yml

@@ -17,3 +17,9 @@ security:
     resource:
       #因为资源服务器得验证你的Token是否有访问此资源的权限以及用户信息，所以只需要一个验证地址
       token-info-uri: http://localhost:8500/sso/oauth/check_token
+feign:
+  oauth2:
+    #开启Oauth支持，这样就会在请求头中携带Token了
+    enabled: true
+    #同时开启负载均衡支持
+    load-balanced: true