Feign调用

淩亂°似流年 2021-10-18 15:15 397阅读 0赞

1.  添加feign的jar包

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

1.  编写Feign的接口服务，用于微服务的提供者和消费者

import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.PostMapping;
    import org.springframework.web.bind.annotation.RequestBody;
    import org.springframework.web.bind.annotation.RequestParam;
    
    @RequestMapping("XXX")
    public interface IFeignService {
        @GetMapping("feign_get")
        String get(@RequestParam("name") String name);
    
        @PostMapping("feign_post")
        User post(@RequestBody User user);
    }

1.  在微服务的提供者一方，实现这个接口服务

import com.qf.feign.IFeignService;
    import com.qf.feign.User;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.PostMapping;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.RestController;
    
    @RestController
    public class UserController implements IFeignService {
        @Value("${server.port}")
        private String port;
    
        @Override
        public String get(String name) {
            return String.format("你好, %s, 调用的是GET方法, 端口为:%s", name, port);
        }
    
        @Override
        public User post(User user) {
            user.setName(user.getName().concat("   POST方法  ").concat(port));
            return user;
        }
    }

1.  在微服务的消费者一方，开启Feign；并实现这个接口服务

import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
    import org.springframework.cloud.client.loadbalancer.LoadBalanced;
    import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
    import org.springframework.cloud.openfeign.EnableFeignClients;
    import org.springframework.context.annotation.Bean;
    import org.springframework.web.client.RestTemplate;
    
    @SpringBootApplication
    @EnableEurekaClient
    @EnableFeignClients
    public class Application extends SpringBootServletInitializer {
        public static void main(String[] args) {
            SpringApplication.run(Application.class, args);
        }
    }

import org.springframework.cloud.openfeign.FeignClient;
    import org.springframework.stereotype.Service;
    
    @Service
    @FeignClient(name = "EUREKA-CLIENT-PROVIDER")
    public interface FeignService extends IFeignService {
    }

接下来就直接注入这个FeignService并调用即可:

import org.springframework.util.LinkedMultiValueMap;
    import org.springframework.util.MultiValueMap;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.RestController;
    import org.springframework.web.client.RestTemplate;
    
    @RestController
    public class UserController {
    
        @Autowired
        private final FeignUserService feignUserService;
    
        @GetMapping("get")
        public String feignGet(@RequestParam(value = "name") String name) {
            return feignUserService.feignGet(name);
        }
    
        @GetMapping("post")
        public String feignPost(@RequestParam(value = "name") String name) {
            return feignUserService.feignPost(name);
        }
    
        @GetMapping("getEntity")
        public User feignGetEntity(User user) {
            return feignUserService.feignGetEntity(user);
        }
    
        @GetMapping("postEntity")
        public User feignPostEntity(User user) {
            return feignUserService.feignPostEntity(user);
        }
    }