【微服务｜openfeign】openfeign开启HttpClient和OkHttp

feign底层的客户端实现：

URLConnection：默认实现，不支持连接池
HttpClient：支持连接池，单例时性能好【和OkHttp】
OkHttp：支持连接池

开启HttpClient

配置文件

feign:
  httpclient:
   # 默认为true
    enabled: true

这时候，我们找到源码：org.springframework.cloud.openfeign.ribbon.HttpClientFeignLoadBalancedConfiguration#feignClient

然后打个断点，启动程序，唰，没反应。

再看看我们的源码，爆红了？？？

要不，我们引入一下httpclient的依赖。

 <dependency>
     <groupId>io.github.openfeign</groupId>
     <artifactId>feign-httpclient</artifactId>
 </dependency>

哎呀，好了，不爆红了，启动一下项目，断点也进来了。

【微服务｜openfeign】openfeign开启HttpClient和OkHttp

那我们来总结一下步骤

修改配置

引入依赖

开启OkHttp

步骤和开启HttpClient一样。

看一眼源码，发现也需要引入依赖。

 <dependency>
     <groupId>io.github.openfeign</groupId>
     <artifactId>feign-okhttp</artifactId>
 </dependency>

附源码：

package org.springframework.cloud.openfeign.ribbon;

import feign.Client;
import feign.okhttp.OkHttpClient;

import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.cloud.netflix.ribbon.SpringClientFactory;
import org.springframework.cloud.openfeign.clientconfig.OkHttpFeignConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;

/**
 * @author Spencer Gibb
 * @author Olga Maciaszek-Sharma
 */
@Configuration(proxyBeanMethods = false)
@ConditionalOnClass(OkHttpClient.class)
@ConditionalOnProperty("feign.okhttp.enabled")
@Import(OkHttpFeignConfiguration.class)
class OkHttpFeignLoadBalancedConfiguration {

 @Bean
 @ConditionalOnMissingBean(Client.class)
 public Client feignClient(CachingSpringLoadBalancerFactory cachingFactory,
   SpringClientFactory clientFactory, okhttp3.OkHttpClient okHttpClient) {
  OkHttpClient delegate = new OkHttpClient(okHttpClient);
  return new LoadBalancerFeignClient(delegate, cachingFactory, clientFactory);
 }

}

package org.springframework.cloud.openfeign.ribbon;

import feign.Client;
import feign.okhttp.OkHttpClient;

import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.cloud.netflix.ribbon.SpringClientFactory;
import org.springframework.cloud.openfeign.clientconfig.OkHttpFeignConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;

/**
 * @author Spencer Gibb
 * @author Olga Maciaszek-Sharma
 */
@Configuration(proxyBeanMethods = false)
@ConditionalOnClass(OkHttpClient.class)
@ConditionalOnProperty("feign.okhttp.enabled")
@Import(OkHttpFeignConfiguration.class)
class OkHttpFeignLoadBalancedConfiguration {

 @Bean
 @ConditionalOnMissingBean(Client.class)
 public Client feignClient(CachingSpringLoadBalancerFactory cachingFactory,
   SpringClientFactory clientFactory, okhttp3.OkHttpClient okHttpClient) {
  OkHttpClient delegate = new OkHttpClient(okHttpClient);
  return new LoadBalancerFeignClient(delegate, cachingFactory, clientFactory);
 }

}