SpringCloud通过Nacos实现注册中心与远程服务调用详解流程

<!--服务注册与发现-->
<dependency>
	<groupId>com.alibaba.cloud</groupId>
	<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
	<version>2021.0.1.0</version>
</dependency>
<!--远程服务调用负载均衡-->
<dependency>
	<groupId>org.springframework.cloud</groupId>
	<artifactId>spring-cloud-loadbalancer</artifactId>
</dependency>

@SpringBootApplication
@EnableDiscoveryClient
public class OrderApplication {
    public static void main(String[] args) {
        SpringApplication.run(OrderApplication.class, args);
    }
}

	@LoadBalanced    // 开启负载均衡策略
    @Bean
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }

    @Autowired
    RestTemplate restTemplate;
    @Autowired
    private DiscoveryClient discoveryClient;
    @GetMapping("/test")
    public String test() throws Exception {
        //可以获取到对应服务的列表 服务名 ip 端口均可从这里面获取到 也可以自己决定调用顺序
        List<ServiceInstance> instances = discoveryClient.getInstances("userservice");
		//get方式调用 
        String template = restTemplate.getForObject("http://userservice/getTime/1123?name=jack", String.class);
        Map<String, Object> resMap = new HashMap<>();
        resMap.put("aaaa", "bbbb");
        //post调用方式
        RequestEntity<Map<String, Object>> requestEntity = RequestEntity
                .post("http://userservice/postTime")
                .contentType(MediaType.APPLICATION_JSON)
                .body(resMap);
        ResponseEntity<Map> responseEntity = restTemplate.exchange(requestEntity, Map.class);]
        log.info("rest -- {}", template + ":" + responseEntity.getBody());
        return template + ":" + responseEntity.getBody();
    }

@GetMapping("/getTime/{uuid}")
public String getTime(@PathVariable String uuid, @RequestParam String name) {
    return new Date().getTime() + ":" + uuid + ":" + name;
}
@PostMapping("/postTime")
public Map<String, Object> getTime(@RequestBody Map<String, Object> params) {
    params.put("time", new Date().getTime());
    return params;
}