Calls between Spring Cloud Services

Micro-service across multiple service of call

Now a student and school micro-micro-service user service school, if the user needs access to school, how should we do?

1. RestTemplate way

Add config

import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.client.RestTemplate;

@Configuration
public class RestTempldateConfig {

　　@Bean
　　@Scope("singleton")
　　@LoadBalanced
　　public RestTemplate restTempldate(){

　　　　RestTemplate restTemplate = new RestTemplate();
　　　　restTemplate.getMessageConverters().clear();
　　　　restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

　　　　return restTemplate;
　　}

}

@LoadBalanced is a load balancing annotation, the default strategy is to find linear polling service

transfer:

Result result = restTemplate.postForObject("http://SPRING-SCHOOL/school/findAll", null,Result.class);
return result;

SPRING-SCHOOL is a school application name

2. Use openfeign see calls for system

The introduction of package

<dependency>
　　<groupId>org.springframework.cloud</groupId>
　　<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>

Write call-side code

import com.lvlvstart.spring.demo.common.entity.School;
import com.lvlvstart.spring.demo.common.msg.Result;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;

import java.util.List;

@FeignClient("SPRING-SCHOOL")
public interface SchoolClient {

 

　　@PostMapping(value = "/school/findAll")
　　public Result<List<School>> findAll();

　　@PostMapping(value = "/school/findById")
　　public Result<School> findById(String schoolId);
}

Start class add comments @EnableFeignClients

@SpringBootApplication
@EnableEurekaClient
@EnableFeignClients("com.lvlvstart.spring.demo.common.client")
public class SpringUserApplication {

　　public static void main(String[] args) {
　　SpringApplication.run(SpringUserApplication.class, args);
　　}

}

transfer

@Autowired
private SchoolClient schoolClient;

@PostMapping("findAllSchool")
public Result findAll(){
　　return schoolClient.findAll();
}

The complete code please visit: https://github.com/halouprogramer/spring-cloud-demo

Calls between Spring Cloud Services

Guess you like