SpringCloud Ribbon负载均衡代码实例

  　　org.springframework.boot 　　spring-boot-starter-web 　　org.springframework.cloud 　　spring-cloud-starter-netflix-eureka-client 　　 　　org.springframework.cloud 　　spring-cloud-starter-netflix-ribbon<!-- lombok --> org.projectlomboklomboktrue

 import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.loadbalancer.LoadBalanced; import org.springframework.context.annotation.Bean; import org.springframework.web.client.RestTemplate; @SpringBootApplication @MapperScan("cn.ytheng.order_service") public class OrderServiceApplication { /** * @Loadbalanced负载均衡策略 */ @Bean @LoadBalanced public RestTemplate restTemplate() { return new RestTemplate(); } public static void main(String[] args) { SpringApplication.run(OrderServiceApplication.class, args); } }

 import cn.theng.order_service.utils.RibbonUtils; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.cloud.client.ServiceInstance; import org.springframework.cloud.client.loadbalancer.LoadBalancerClient; import org.springframework.util.LinkedMultiValueMap; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.client.RestTemplate; import java.util.HashMap; import java.util.Map; @RestController @RequestMapping("/api/v1/order") public class ProductOrderController { @RequestMapping("/test") public Object test(@RequestParam("product_id") int productId) { //方法一 //    ServiceInstance instance = loadBalancerClient.choose("product-service"); //    String url = String.format("http://%s:%s/api/v1/product/find?id=" + productId, instance.getHost(), instance.getPort()); //    RestTemplate template = new RestTemplate(); //    Map map2 = template.getForObject(url, Map.class); //负载均衡 //商品列表启用两个节点时 //由客户端来自动选择节点，可能是8771端口，也有可能是8772端口 //参数id名称需要保持一致 //方法二(推荐) String uri = "http://product-service/api/v1/product/find?id={id}"; Map request = new HashMap(); request.put("id", productId); Map map3 = RibbonUtils.get(uri, Map.class, request); return "success"; } @PostMapping("/test2") public Object test2(@RequestParam("product_id") int productId) { Product product = new Product(); product.setId(productId); String uri = "http://product-service/api/v1/product/find2"; LinkedMultiValueMap headers = new LinkedMultiValueMap(); headers.add("token", "theng"); Object result = RibbonUtils.post(uri, Object.class, product, headers); return "success"; } }

 import org.springframework.beans.factory.annotation.Autowired; import org.springframework.http.*; import org.springframework.stereotype.Component; import org.springframework.util.LinkedMultiValueMap; import org.springframework.web.client.RestTemplate; import javax.annotation.PostConstruct; import java.util.Arrays; import java.util.Collections; import java.util.Map; @Component public class RibbonUtils { @Autowired private RestTemplate restTemplate; private static RestTemplate template; //@PostConstruct修饰的方法会在服务器加载Servlet的时候运行，并且只会被服务器调用一次 @PostConstruct public void init() { template = restTemplate; } /** * * @param uri 接口地址 * @param responseType 返回类型 * * */ public static  T get(String uri, Class responseType) { return template.getForObject(uri, responseType); } /** * * @param uri 接口地址 * @param responseType 返回类型 * @param request 传递参数 * * */ public static  T get(String uri, Class responseType, Map request) { return template.getForObject(uri, responseType, request); } /** * * @param ur<div style="color:transparent">来源gaodai.ma#com搞#代!码网</div>i 接口地址 * @param responseType 返回类型 * @param request 传递参数 * @param headerMap 报头信息 * * */ public static  T get(String uri, Class responseType, Map request, Map headerMap) { //添加报头 HttpHeaders headers = new HttpHeaders(); headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON)); for(Map.Entry entry : headerMap.entrySet()){ String mapKey = entry.getKey(); String mapValue = entry.getValue(); headers.add(mapKey, mapValue); } //body的类型定为String,这里使用get没有用到body,post会使用到 HttpEntity entity = new HttpEntity(null, headers); ResponseEntity result = template.exchange(uri, HttpMethod.GET, entity, responseType, request); return result.getBody(); } /** * * @param uri 接口地址 * @param responseType 返回类型 * @param body 传递实体 * @param headers 报头信息 * * */ public static  T post(String uri, Class responseType, Object body, LinkedMultiValueMap headers) { if (!headers.containsKey("Content-Type")) { headers.put("Content-Type", Collections.singletonList("application/json;charset=UTF-8")); } HttpEntity request = new HttpEntity(body, headers); Object obj = template.postForObject(uri, request, responseType); return (T) obj; } }