1. Maven 添加依赖
<dependency> <groupId>com.squareup.okhttp3</groupId> <artifactId>okhttp</artifactId> <version>3.10.0</version></dependency>
2. application.properties 配置文件
ok.http.connect-timeout=30ok.http.read-timeout=30ok.http.write-timeout=30# 连接池中整体的空闲连接的最大数量ok.http.max-idle-connections=200# 连接空闲时间最多为 300 秒ok.http.keep-alive-duration=300
3. OkHttpConfiguration 配置类
import okhttp3.ConnectionPool;import okhttp3.OkHttpClient;import org.springframework.beans.factory.annotation.Value;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import javax.net.ssl.*;import java.security.*;import java.security.cert.CertificateException;import java.security.cert.X509Certificate;import java.util.concurrent.TimeUnit;/** * @author Answer.AI.L * @date 2019-04-09 */@Configurationpublic class OkHttpConfiguration { @Value("${ok.http.connect-timeout}") private Integer connectTimeout; @Value("${ok.http.read-timeout}") private Integer readTimeout; @Value("${ok.http.write-timeout}") private Integer writeTimeout; @Value("${ok.http.max-idle-connections}") private Integer maxIdleConnections; @Value("${ok.http.keep-alive-duration}") private Long keepAliveDuration; @Bean public OkHttpClient okHttpClient() { return new OkHttpClient.Builder() .sslSocketFactory(sslSocketFactory(), x509TrustManager()) // 是否开启缓存 .retryOnConnectionFailure(false) .connectionPool(pool()) .connectTimeout(connectTimeout, TimeUnit.SECONDS) .readTimeout(readTimeout, TimeUnit.SECONDS) .writeTimeout(writeTimeout,TimeUnit.SECONDS) .hostnameVerifier((hostname, session) -> true) // 设置代理// .proxy(new Proxy(Proxy.Type.HTTP, new InetSocketAddress("127.0.0.1", 8888))) // 拦截器// .addInterceptor() .build(); } @Bean public X509TrustManager x509TrustManager() { return new X509TrustManager() { @Override public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException { } @Override public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException { } @Override public X509Certificate[] getAcceptedIssuers() { return new X509Certificate[0]; } }; } @Bean public SSLSocketFactory sslSocketFactory() { try { // 信任任何链接 SSLContext sslContext = SSLContext.getInstance("TLS"); sslContext.init(null, new TrustManager[]{x509TrustManager()}, new SecureRandom()); return sslContext.getSocketFactory(); } catch (NoSuchAlgorithmException | KeyManagementException e) { e.printStackTrace(); } return null; } @Bean public ConnectionPool pool() { return new ConnectionPool(maxIdleConnections, keepAliveDuration, TimeUnit.SECONDS); }}
4. OkHttp 类
import lombok.extern.slf4j.Slf4j;import okhttp3.*;import org.apache.commons.lang3.exception.ExceptionUtils;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Component;import java.util.Map;/** * @author Answer.AI.L * @date 2019-04-09 */@Slf4j@Componentpublic class OkHttpCli { private static final MediaType JSON = MediaType.parse("application/json; charset=utf-8"); private static final MediaType XML = MediaType.parse("application/xml; charset=utf-8"); @Autowired private OkHttpClient okHttpClient; /** * get 请求 * @param url 请求url地址 * @return string * */ public String doGet(String url) { return doGet(url, null, null); } /** * get 请求 * @param url 请求url地址 * @param params 请求参数 map * @return string * */ public String doGet(String url, Map<String, String> params) { return doGet(url, params, null); } /** * get 请求 * @param url 请求url地址 * @param headers 请求头字段 {k1, v1 k2, v2, ...} * @return string * */ public String doGet(String url, String[] headers) { return doGet(url, null, headers); } /** * get 请求 * @param url 请求url地址 * @param params 请求参数 map * @param headers 请求头字段 {k1, v1 k2, v2, ...} * @return string * */ public String doGet(String url, Map<String, String> params, String[] headers) { StringBuilder sb = new StringBuilder(url); if (params != null && params.keySet().size() > 0) { boolean firstFlag = true; for (String key : params.keySet()) { if (firstFlag) { sb.append("?").append(key).append("=").append(params.get(key)); firstFlag = false; } else { sb.append("&").append(key).append("=").append(params.get(key)); } } } Request.Builder builder = new Request.Builder(); if (headers != null && headers.length > 0) { if (headers.length % 2 == 0) { for (int i = 0; i < headers.length; i = i + 2) { builder.addHeader(headers[i], headers[i + 1]); } } else { log.warn("headers's length[{}] is error.", headers.length); } } Request request = builder.url(sb.toString()).build(); log.info("do get request and url[{}]", sb.toString()); return execute(request); } /** * post 请求 * @param url 请求url地址 * @param params 请求参数 map * @return string */ public String doPost(String url, Map<String, String> params) { FormBody.Builder builder = new FormBody.Builder(); if (params != null && params.keySet().size() > 0) { for (String key : params.keySet()) { builder.add(key, params.get(key)); } } Request request = new Request.Builder().url(url).post(builder.build()).build(); log.info("do post request and url[{}]", url); return execute(request); } /** * post 请求, 请求数据为 json 的字符串 * @param url 请求url地址 * @param json 请求数据, json 字符串 * @return string */ public String doPostJson(String url, String json) { log.info("do post request and url[{}]", url); return exectePost(url, json, JSON); } /** * post 请求, 请求数据为 xml 的字符串 * @param url 请求url地址 * @param xml 请求数据, xml 字符串 * @return string */ public String doPostXml(String url, String xml) { log.info("do post request and url[{}]", url); return exectePost(url, xml, XML); } private String exectePost(String url, String data, MediaType contentType) { RequestBody requestBody = RequestBody.create(contentType, data); Request request = new Request.Builder().url(url).post(requestBody).build(); return execute(request); } private String execute(Request request) { Response response = null; try { response = okHttpClient.newCall(request).execute(); if (response.isSuccessful()) { return response.body().string(); } } catch (Exception e) { log.error(ExceptionUtils.getStackTrace(e)); } finally { if (response != null) { response.close(); } } return ""; }}
5. 使用验证
@RestControllerpublic class AnswerController { @Autowired private OkHttpCli okHttpCli; @RequestMapping(value = "show", method = RequestMethod.GET) public String show() { String url = "https://www.baidu.com/"; String message = okHttpCli.doGet(url); return message; } }
6. 双向认证(待证)
@Beanpublic SSLSocketFactory sslSocketFactory() { String certPath = ""; String caPath = ""; String certPwd = ""; String caPwd = ""; try { ClassPathResource selfcertPath = new ClassPathResource(certPath); ClassPathResource trustcaPath = new ClassPathResource(caPath); KeyStore selfCert = KeyStore.getInstance("pkcs12"); selfCert.load(selfcertPath.getInputStream(), certPwd.toCharArray()); KeyManagerFactory kmf = KeyManagerFactory.getInstance("sunx509"); kmf.init(selfCert, certPwd.toCharArray()); KeyStore caCert = KeyStore.getInstance("jks"); caCert.load(trustcaPath.getInputStream(), caPwd.toCharArray()); TrustManagerFactory tmf = TrustManagerFactory.getInstance("sunx509"); tmf.init(caCert); SSLContext sslContext = SSLContext.getInstance("TLS"); sslContext.init(kmf.getKeyManagers(), tmf.getTrustManagers(), null); return sslContext.getSocketFactory(); } catch (Exception e) { e.printStackTrace(); } return null;}
补充：Spring Cloud Feign 总结问题，注意点，性能调优，切换okhttp3
Feign常见问题总结
FeignClient接口如使用@PathVariable ，必须指定value属性
//在一些早期版本中， @PathVariable("id") 中的 "id" ，也就是value属性，必须指定，不能省略。@FeignClient("microservice-provider-user")public interface UserFeignClient { @RequestMapping(value = "/simple/{id}", method = RequestMethod.GET) public User findById(@PathVariable("id") Long id); ...}
Java代码自定义Feign Client的注意点与坑
@FeignClient(name = "microservice-provider-user", configuration = UserFeignConfig.class)public interface UserFeignClient { @GetMapping("/users/{id}") User findById(@PathVariable("id") Long id);}/** * 该Feign Client的配置类，注意： * 1. 该类可以独立出去； * 2. 该类上也可添加@Configuration声明是一个配置类； * 配置类上也可添加@Configuration注解，声明这是一个配置类； * 但此时千万别将该放置在主应用程序上下文@ComponentScan所扫描的包中， * 否则，该配置将会被所有Feign Client共享，无法实现细粒度配置！ * 个人建议：像我一样，不加@Configuration注解 * * @author zhouli */class UserFeignConfig { @Bean public Logger.Level logger() { return Logger.Level.FULL; }}
配置类上也可添加@Configuraiton 注解，声明这是一个配置类；但此时千万别将该放置在主应用程序上下文@ComponentScan 所扫描的包中，否则，该配置将会被所有Feign Client共享（相当于变成了通用配置，其实本质还是Spring父子上下文扫描包重叠导致的问题），无法实现细粒度配置！
个人建议：像我一样，不加@Configuration注解，省得进坑。
最佳实践：尽量用配置属性自定义Feign的配置！！！
@FeignClient 注解属性
//@FeignClient(name = "microservice-provider-user")//在早期的Spring Cloud版本中，无需提供name属性，从Brixton版开始，@FeignClient必须提供name属性，否则应用将无法正常启动！//另外，name、url等属性支持占位符。例如：@FeignClient(name = "${feign.name}", url = "${feign.url}")
类级别的@RequestMapping会被Spring MVC加载
@RequestMapping("/users")@FeignClient(name = "microservice-user")public class TestFeignClient { // ...}
类上的@RequestMapping 注解也会被Spring MVC加载。该问题现已经被解决，早期的版本有两种解决方案：方案1：不在类上加@RequestMapping 注解；方案2：添加如下代码：
@Configuration@ConditionalOnClass({ Feign.class })public class FeignMappingDefaultConfiguration { @Bean public WebMvcRegistrations feignWebRegistrations() { return new WebMvcRegistrationsAdapter() { @Override public RequestMappingHandlerMapping getRequestMappingHandlerMapping() { return new FeignFilterRequestMappingHandlerMapping(); } }; } private static class FeignFilterRequestMappingHandlerMapping extends RequestMappingHandlerMapping { @Override protected boolean isHandler(Class<?> beanType) { return super.isHandler(beanType) && !beanType.isInterface(); } }}
首次请求失败Ribbon的饥饿加载(eager-load)模式
如需产生Hystrix Stream监控信息，需要做一些额外操作Feign本身已经整合了Hystrix，可直接使用@FeignClient(value = “microservice-provider-user”, fallback = XXX.class) 来指定fallback类，fallback类继承@FeignClient所标注的接口即可。
但是假设如需使用Hystrix Stream进行监控，默认情况下，访问http://IP:PORT/actuator/hystrix.stream 是会返回404，这是因为Feign虽然整合了Hystrix，但并没有整合Hystrix的监控。如何添加监控支持呢？需要以下几步：
第一步：添加依赖，示例：
<!-- 整合hystrix，其实feign中自带了hystrix，引入该依赖主要是为了使用其中的hystrix-metrics-event-stream，用于dashboard --><dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-hystrix</artifactId></dependency>
第二步：在启动类上添加@EnableCircuitBreaker 注解，示例：
@SpringBootApplication@EnableFeignClients@EnableDiscoveryClient@EnableCircuitBreakerpublic class MovieFeignHystrixApplication { public static void main(String[] args) { SpringApplication.run(MovieFeignHystrixApplication.class, args); }}
第三步：在application.yml中添加如下内容，暴露hystrix.stream端点：
management: endpoints: web: exposure: include: 'hystrix.stream'
这样，访问任意Feign Client接口的API后，再访问http://IP:PORT/actuator/hystrix.stream ，就会展示一大堆Hystrix监控数据了。
Feign 上传文件
加依赖
<dependency> <groupId>io.github.openfeign.form</groupId> <artifactId>feign-form</artifactId> <version>3.0.3</version></dependency><dependency> <groupId>io.github.openfeign.form</groupId> <artifactId>feign-form-spring</artifactId> <version>3.0.3</version></dependency>
编写Feign Client
@FeignClient(name = "ms-content-sample", configuration = UploadFeignClient.MultipartSupportConfig.class)public interface UploadFeignClient { @RequestMapping(value = "/upload", method = RequestMethod.POST, produces = {MediaType.APPLICATION_JSON_UTF8_VALUE}, consumes = MediaType.MULTIPART_FORM_DATA_VALUE) @ResponseBody String handleFileUpload(@RequestPart(value = "file") MultipartFile file); class MultipartSupportConfig { @Bean public Encoder feignFormEncoder() { return new SpringFormEncoder(); } }}
如代码所示，在这个Feign Client中，我们引用了配置类MultipartSupportConfig ，在MultipartSupportConfig 中，我们实例化了SpringFormEncoder 。这样这个Feign Client就能够上传啦。
注意点
//RequestMapping注解中的produeces 、consumes 不能少；@RequestMapping(value = "/upload", method = RequestMethod.POST, produces = {MediaType.APPLICATION_JSON_UTF8_VALUE}, consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
接口定义中的注解@RequestPart(value = “file”) 不能写成@RequestParam(value = “file”） 。
最好将Hystrix的超时时间设长一点，例如5秒，否则可能文件还没上传完，Hystrix就超时了，从而导致客户端侧的报错。
Feign实现Form表单提交
添加依赖：
<dependency> <groupId>io.github.openfeign.form</groupId> <artifactId>feign-form</artifactId> <version>3.2.2</version></dependency><dependency> <groupId>io.github.openfeign.form</groupId> <artifactId>feign-form-spring</artifactId> <version>3.2.2</version></dependency>
Feign Client示例：
@FeignClient(name = "xxx", url = "http://www.itmuch.com/", configuration = TestFeignClient.FormSupportConfig.class)public interface TestFeignClient { @PostMapping(value = "/test", consumes = {MediaType.APPLICATION_FORM_URLENCODED_VALUE}, produces = {MediaType.APPLICATION_JSON_UTF8_VALUE} ) void post(Map<String, ?> queryParam); class FormSupportConfig { @Autowired private ObjectFactory<HttpMessageConverters> messageConverters; // new一个form编码器，实现支持form表单提交 @Bean public Encoder feignFormEncoder() { return new SpringFormEncoder(new SpringEncoder(messageConverters)); } // 开启Feign的日志 @Bean public Logger.Level logger() { return Logger.Level.FULL; } }}
调用示例：
@GetMapping("/user/{id}")public User findById(@PathVariable Long id) { HashMap<String, String> param = Maps.newHashMap(); param.put("username","zhangsan"); param.put("password","pwd"); this.testFeignClient.post(param); return new User();}
日志：
...[TestFeignClient#post] ---> POST http://www.baidu.com/test HTTP/1.1...[TestFeignClient#post] Accept: application/json;charset=UTF-8...[TestFeignClient#post] Content-Type: application/x-www-form-urlencoded; charset=UTF-8...[TestFeignClient#post] Content-Length: 30...[TestFeignClient#post] ...[TestFeignClient#post] password=pwd&username=zhangsan...[TestFeignClient#post] ---> END HTTP (30-byte body)
由日志可知，此时Feign已能使用Form表单方式提交数据。
Feign GET请求如何构造多参数
假设需请求的URL包含多个参数，例如http://microservice-provider-user/get?id=1&username=张三 ，该如何使用Feign构造呢？我们知道，Spring Cloud为Feign添加了Spring MVC的注解支持，那么我们不妨按照Spring MVC的写法尝试一下：
@FeignClient("microservice-provider-user")public interface UserFeignClient { @RequestMapping(value = "/get", method = RequestMethod.GET) public User get0(User user);}
然而，这种写法并不正确，控制台会输出类似如下的异常。
feign.FeignException: status 405 reading UserFeignClient#get0(User); content:{"timestamp":1482676142940,"status":405,"error":"Method Not Allowed","exception":"org.springframework.web.HttpRequestMethodNotSupportedException","message":"Request method 'POST' not supported","path":"/get"}
由异常可知，尽管我们指定了GET方法，Feign依然会使用POST方法发送请求。于是导致了异常。正确写法如下
方法一[推荐]注意:使用该方法无法使用Fegin的继承模式
@FeignClient("microservice-provider-user")public interface UserFeignClient { @GetMapping("/get") public User get0(@SpringQueryMap User user);}
方法二[推荐]
@FeignClient(name = "microservice-provider-user")public interface UserFeignClient { @RequestMapping(value = "/get", method = RequestMethod.GET) public User get1(@RequestParam("id") Long id, @RequestParam("username") String username);}
这是最为直观的方式，URL有几个参数，Feign接口中的方法就有几个参数。使用@RequestParam注解指定请求的参数是什么。
方法三[不推荐]多参数的URL也可使用Map来构建。当目标URL参数非常多的时候，可使用这种方式简化Feign接口的编写。
@FeignClient(name = "microservice-provider-user")public interface UserFeignClient { @RequestMapping(value = "/get", method = RequestMethod.GET) public User get2(@RequestParam Map<String, Object> map);}
在调用时，可使用类似以下的代码。
public User get(String username, String password) { HashMap<String, Object> map = Maps.newHashMap(); map.put("id", "1"); map.put("username", "张三"); return this.userFeignClient.get2(map);}
注意：这种方式不建议使用。主要是因为可读性不好，而且如果参数为空的时候会有一些问题，例如map.put(“username”, null); 会导致服务调用方（消费者服务）接收到的username是”” ，而不是null。
切换为 Okhttp3 提升 QPS 性能优化
加依赖引入okhttp3
<dependency> <groupId>io.github.openfeign</groupId> <artifactId>feign-okhttp</artifactId> <version>${version}</version></dependency>
写配置
feign: # feign启用hystrix，才能熔断、降级 # hystrix: # enabled: true # 启用 okhttp 关闭默认 httpclient httpclient: enabled: false #关闭httpclient # 配置连接池 max-connections: 200 #feign的最大连接数 max-connections-per-route: 50 #fegin单个路径的最大连接数 okhttp: enabled: true # 请求与响应的压缩以提高通信效率 compression: request: enabled: true min-request-size: 2048 mime-types: text/xml,application/xml,application/json response: enabled: true
参数配置
/** * 配置 okhttp 与连接池 * ConnectionPool 默认创建5个线程，保持5分钟长连接 */@Configuration@ConditionalOnClass(Feign.class)@AutoConfigureBefore(FeignAutoConfiguration.class) //SpringBoot自动配置public class OkHttpConfig { // 默认老外留给你彩蛋中文乱码，加上它就 OK @Bean public Encoder encoder() { return new FormEncoder(); } @Bean public okhttp3.OkHttpClient okHttpClient() { return new okhttp3.OkHttpClient.Builder() //设置连接超时 .connectTimeout(10, TimeUnit.SECONDS) //设置读超时 .readTimeout(10, TimeUnit.SECONDS) //设置写超时 .writeTimeout(10, TimeUnit.SECONDS) //是否自动重连 .retryOnConnectionFailure(true) .connectionPool(new ConnectionPool(10, 5L, TimeUnit.MINUTES)) .build(); }}
以上为个人经验，希望能给大家一个参考，也希望大家多多支持。如有错误或未考虑完全的地方，望不吝赐教。
烦恼忧愁不用追，吃点好的别嫌贵，
