文件目录结构
文件目录结构很重要,特别注意的是rule文件要放在主启动类上一级位置,才能够扫描。
写pom
- <dependencies>
- <!--springboot 2.2.2-->
- <dependency>
- <groupId>org.springframework.boot</groupId>
- <artifactId>spring-boot-starter-web</artifactId>
- </dependency>
- <!--Spring cloud Hoxton.SR1-->
- <dependency>
- <groupId>org.springframework.boot</groupId>
- <artifactId>spring-boot-starter-actuator</artifactId>
- </dependency>
- <!--Spring cloud alibaba 2.1.0.RELEASE-->
- <dependency>
- <groupId>org.projectlombok</groupId>
- <artifactId>lombok</artifactId>
- <optional>true</optional>
- </dependency>
- <dependency>
- <groupId>org.springframework.boot</groupId>
- <artifactId>spring-boot-starter-test</artifactId>
- <scope>test</scope>
- </dependency>
- <!--Eureka-Client-->
- <dependency>
- <groupId>org.springframework.cloud</groupId>
- <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
- </dependency>
因为eureka的依赖已经整合了ribbon的依赖,所以不用额外引入新的东西。
改yml
- server:
- port: 80
- spring:
- application:
- name: cloud-book-consumer
- eureka:
- client:
- register-with-eureka: false
- fetch-registry: true
- service-url:
- defaultZone: http://eureka7001.com:7001/eureka,http://eureka7002.com:7002/eureka
主启动
- @SpringBootApplication
- @EnableEurekaClient
- @RibbonClient(name = "CLOUD-BOOK-SERVICE", configuration = LoadBalanceRule.class) //更换轮询算法
- public class RestTemplateMain80 {
- public static void main(String[] args) {
- SpringApplication.run(RestTemplateMain80.class,args);
- }
- }
业务逻辑
rules层
在图示文件目录下新建LoadBalanceRule.class,用于更换负载均衡算法。
- @Configuration
- public class LoadBalanceRule {
- @Bean
- public IRule iRule() {
- // 定义为随机
- return new RandomRule();
- }
- }
config层
开启restTemplate负载均衡
在config文件夹下创建LoadBalanceConfig.class
- @Configuration
- public class LoadBalanceConfig {
- @Bean
- @LoadBalanced //开启负载均衡
- public RestTemplate getReatTemplate(){
- return new RestTemplate();
- }
- }
controller层
新建BookController.class
写业务代码
- @RestController
- @Slf4j
- public class BookController {
- @Resource
- private RestTemplate restTemplate;
- public static final String PAYMENT_URL = "http://CLOUD-BOOK-SERVICE";
- @GetMapping(value = "restTemplate/book/getAllBooks")//只要json数据时
- public CommonResult getAllBooks(){
- return restTemplate.getForObject(PAYMENT_URL+"/book/getAllBooks",CommonResult.class);
- }
- @GetMapping("restTemplate/book/getAllBooks2") //需要知道更多数据时,使用getForEntity方法
- public CommonResult getAllBooks2(){
- ResponseEntity<CommonResult> resultResponseEntit = restTemplate.getForEntity(PAYMENT_URL+"/book/getAllBooks",CommonResult.class);
- if (resultResponseEntit.getStatusCode().is2xxSuccessful()){
- log.info(resultResponseEntit.getStatusCode()+"\t"+resultResponseEntit.getHeaders());
- return resultResponseEntit.getBody();
- }else {
- return new CommonResult<>(444,"操作失败");
- }
- }
- @GetMapping(value = "restTemplate/book/index")
- public String index() {
- return restTemplate.getForObject(PAYMENT_URL+"/book/index",String.class);
- }
- }
使用restTemplate+Ribboin实现服务调用和负载均衡完成。
手写Ribbon负载均衡算法 lb层
1.新建LoadBalancer接口,添加代码
- public interface LoadBalancer {
- ServiceInstance instances(List<ServiceInstance> serviceInstances);
- }
2.新建实现类MyLB
- @Component
- public class MyLB implements LoadBalancer {
- private AtomicInteger atomicInteger = new AtomicInteger(0);
- //求第几次访问 自旋锁思想
- public final int getAndIncrement(){
- int current;
- int next;
- do {
- current = this.atomicInteger.get();
- next = current >=2147483647 ? 0 : current+1;
- }while(!this.atomicInteger.compareAndSet(current,next));
- System.out.println("***第几次访问next->"+next);
- return next;
- }
- //负载均衡算法,实现roundRobin算法
- @Override
- public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
- int index = getAndIncrement() % serviceInstances.size();
- return serviceInstances.get(index);
- }
- }
修改BookController
- @RestController
- @Slf4j
- public class BookController {
- @Resource
- private RestTemplate restTemplate;
- @Resource
- private LoadBalancer loadBalancer;
- @Resource
- private DiscoveryClient discoveryClient;
- public static final String PAYMENT_URL = "http://CLOUD-BOOK-SERVICE";
- @GetMapping(value = "restTemplate/book/getAllBooks")//只要json数据时
- public CommonResult getAllBooks(){
- List<ServiceInstance> instances = discoveryClient.getInstances("CLOUD-BOOK-SERVICE");
- if (instances == null || instances.size() <= 0){
- return null;
- }
- ServiceInstance serviceInstance = loadBalancer.instances(instances);
- URI uri = serviceInstance.getUri();
- return restTemplate.getForObject(uri+"/book/getAllBooks",CommonResult.class);
- }
- @GetMapping(value = "restTemplate/book/index")
- public String index() {
- List<ServiceInstance> instances = discoveryClient.getInstances("CLOUD-BOOK-SERVICE");
- if (instances == null || instances.size() <= 0){
- return null;
- }
- ServiceInstance serviceInstance = loadBalancer.instances(instances);
- URI uri = serviceInstance.getUri();
- return restTemplate.getForObject(uri+"/book/index",String.class);
- }
- }
修改文件注解
- 删去主启动类的更换负载均衡算法注解
@RibbonClient(name = “CLOUD-BOOK-SERVICE”, configuration = LoadBalanceRule.class)
- 删去LoadBalanceConfig中开启负载均衡算法注解
@LoadBalanced
手写Ribbon算法并使用完成
以上就是Ribbon和RestTemplate实现服务调用与负载均衡的详细内容,更多关于Ribbon和RestTemplate服务与负载的资料请关注服务器之家其它相关文章!
原文链接:https://blog.csdn.net/super1223/article/details/115384982