springcloud之FeignClient使用详解

package com.demo.DemoFeignClient;

/**
 * 微服务之间调用的核心接口     Aikes
 * 注解@FeignClient中contextID参数用于标识client，防止多个接口共用同一个目标FeignClient冲突
 */
@FeignClient(name = "A-server" ,contextId = "DemoFeignClient", fallback = DemoFeignClientFallback.class )
public interface DemoFeignClient{

    @PostMapping("/demoServer/testMicroServiceAccess")
    public ApiResponse<String> testMicroServiceAccess(@RequestBody ServerAccessRequest<DemoPo> cServerAccessRequest);
}

/**
 * 增加访问失败时的处理逻辑
 */
@Component
class DemoFeignClientFallback implements DemoFeignClient{

    @Override
    public ApiResponse<String> testMicroServiceAccess(ServerAccessRequest<DemoPo> cServerAccessRequest) {
        ApiResponse<String> tApiResponse = new ApiResponse<>();
        tApiResponse.setStatus(ApiResponse.BUSY);
        return tApiResponse;
    }
}

package com.demo.DemoFeignServerController;

/**
 * 服务提供方    Aikes
 */
@Controller
@RequestMapping("demoServer")
@RestController
@Slf4j
public class DemoFeignServerController {

    @PostMapping("/testMicroServiceAccess")
    public ApiResponse<String> testMicroServiceAccess(@RequestBody ServerAccessRequest<DemoPo> cServerAccessRequest) {
        log.info(cServerAccessRequest.toString());
        log.info("This is FeignServerController");
        ApiResponse<String> tApiResponse = new ApiResponse<String>();
        tApiResponse.setStatus(ApiResponse.SUCCESS);
        tApiResponse.setStatusText(ApiResponse.SUCCESS_TEXT);
        tApiResponse.setData(cServerAccessRequest.getData().getDemoName());
        return tApiResponse;
    }
}

package com.demo.DemoFeignClientController;

/**
 * 服务消费方    Aikes
 */
public class DemoFeignClientController {

    @Autowired
    private DemoFeignClient mDemoFeignClient;

    public void doService() {
        //TODO 业务处理
        ApiResponse<String> tApiResponse = this.testFeign();//调用 A微服务 处理逻辑
        //TODO 处理返回结果
    }

    public ApiResponse<String> testFeign() {
        ServerAccessRequest<DemoPo> tServerAccessRequest = new ServerAccessRequest<DemoPo>();
        tServerAccessRequest.setBusinessNo("TEST001");
        return mDemoFeignClient.testMicroServiceAccess(tServerAccessRequest);
    }
}