Feign配置

1.引入jar

        <!--feign客户端依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>

2.编写Feign接口

@FeignClient(value = "userservice",configuration = DefaultFeignConfiguration.class)
public interface UserClient {

    @GetMapping("/user/{id}")
    public User queryById(@PathVariable("id") Long id);

}

3.启动类增加Feign注解

@EnableFeignClients(defaultConfiguration = DefaultFeignConfiguration.class)

4.DefaultFeignConfiguration配置Feign日志级别，放在启动类上作用全局，放在Feign接口上作用接口

public class DefaultFeignConfiguration {

    @Bean
    public Logger.Level logLevel(){
        return Logger.Level.FULL;
    }
}

5.配置文件配置Feign日志级别，default代表全局，指定userservice代表指定服务

feign:
  client:
    config:
      #userservice:
      default:
        loggerLevel: FULL

 6.Feign优化

（1）日志级别尽量使用basic或者default。

（2）使用httpClient或者OKHttp代替URLconnection，引入jar包，修改配置文件。

        <!--引入HttpClient依赖-->
        <dependency>
            <groupId>io.github.openfeign</groupId>
            <artifactId>feign-httpclient</artifactId>
        </dependency>

feign:
  httpclient:
    enabled: true
    max-connections: 200
    max-connections-per-route: 50