1. Maven 添加依賴

<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# 連接池中整體的空閑連接的最大數量ok.http.max-idle-connections=200# 連接空閑時間最多為 300 秒ok.http.keep-alive-duration=3003. OkHttpConfiguration 配置類

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()) // 是否開啟緩存 .retryOnConnectionFailure(false) .connectionPool(pool()) .connectTimeout(connectTimeout, TimeUnit.SECONDS) .readTimeout(readTimeout, TimeUnit.SECONDS) .writeTimeout(writeTimeout,TimeUnit.SECONDS) .hostnameVerifier((hostname, session) -> true) // 設置代理// .proxy(new Proxy(Proxy.Type.HTTP, new InetSocketAddress('127.0.0.1', 8888))) // 攔截器// .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 { // 信任任何鏈接 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 類

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 請求 * @param url 請求url地址 * @return string * */ public String doGet(String url) { return doGet(url, null, null); } /** * get 請求 * @param url 請求url地址 * @param params 請求參數 map * @return string * */ public String doGet(String url, Map<String, String> params) { return doGet(url, params, null); } /** * get 請求 * @param url 請求url地址 * @param headers 請求頭字段 {k1, v1 k2, v2, ...} * @return string * */ public String doGet(String url, String[] headers) { return doGet(url, null, headers); } /** * get 請求 * @param url 請求url地址 * @param params 請求參數 map * @param headers 請求頭字段 {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 請求 * @param url 請求url地址 * @param params 請求參數 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 請求, 請求數據為 json 的字符串 * @param url 請求url地址 * @param json 請求數據, 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 請求, 請求數據為 xml 的字符串 * @param url 請求url地址 * @param xml 請求數據, 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. 使用驗證

@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. 雙向認證(待證)

@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;}

補充：Spring Cloud Feign 總結問題，注意點，性能調優，切換okhttp3

Feign常見問題總結

FeignClient接口如使用@PathVariable ，必須指定value屬性

//在一些早期版本中， @PathVariable('id') 中的 'id' ，也就是value屬性，必須指定，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代碼自定義Feign Client的注意點與坑

@FeignClient(name = 'microservice-provider-user', configuration = UserFeignConfig.class)public interface UserFeignClient { @GetMapping('/users/{id}') User findById(@PathVariable('id') Long id);}/** * 該Feign Client的配置類，注意： * 1. 該類可以獨立出去； * 2. 該類上也可添加@Configuration聲明是一個配置類； * 配置類上也可添加@Configuration注解，聲明這是一個配置類； * 但此時千萬別將該放置在主應用程序上下文@ComponentScan所掃描的包中， * 否則，該配置將會被所有Feign Client共享，無法實現細粒度配置！ * 個人建議：像我一樣，不加@Configuration注解 * * @author zhouli */class UserFeignConfig { @Bean public Logger.Level logger() { return Logger.Level.FULL; }}

配置類上也可添加@Configuraiton 注解，聲明這是一個配置類；但此時千萬別將該放置在主應用程序上下文@ComponentScan 所掃描的包中，否則，該配置將會被所有Feign Client共享（相當于變成了通用配置，其實本質還是Spring父子上下文掃描包重疊導致的問題），無法實現細粒度配置！

個人建議：像我一樣，不加@Configuration注解，省得進坑。

最佳實踐：盡量用配置屬性自定義Feign的配置！！！

@FeignClient 注解屬性

//@FeignClient(name = 'microservice-provider-user')//在早期的Spring Cloud版本中，無需提供name屬性，從Brixton版開始，@FeignClient必須提供name屬性，否則應用將無法正常啟動！//另外，name、url等屬性支持占位符。例如：@FeignClient(name = '${feign.name}', url = '${feign.url}')

類級別的@RequestMapping會被Spring MVC加載

@RequestMapping('/users')@FeignClient(name = 'microservice-user')public class TestFeignClient { // ...}

類上的@RequestMapping 注解也會被Spring MVC加載。該問題現已經被解決，早期的版本有兩種解決方案：方案1：不在類上加@RequestMapping 注解；方案2：添加如下代碼：

@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(); } }}

首次請求失敗Ribbon的饑餓加載(eager-load)模式

如需產生Hystrix Stream監控信息，需要做一些額外操作Feign本身已經整合了Hystrix，可直接使用@FeignClient(value = 'microservice-provider-user', fallback = XXX.class) 來指定fallback類，fallback類繼承@FeignClient所標注的接口即可。

但是假設如需使用Hystrix Stream進行監控，默認情況下，訪問http://IP:PORT/actuator/hystrix.stream 是會返回404，這是因為Feign雖然整合了Hystrix，但并沒有整合Hystrix的監控。如何添加監控支持呢？需要以下幾步：

第一步：添加依賴，示例：

<!-- 整合hystrix，其實feign中自帶了hystrix，引入該依賴主要是為了使用其中的hystrix-metrics-event-stream，用于dashboard --><dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-hystrix</artifactId></dependency>

第二步：在啟動類上添加@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中添加如下內容，暴露hystrix.stream端點：

management: endpoints: web: exposure: include: ’hystrix.stream’

這樣，訪問任意Feign Client接口的API后，再訪問http://IP:PORT/actuator/hystrix.stream ，就會展示一大堆Hystrix監控數據了。

Feign 上傳文件

加依賴

<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>

編寫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(); } }}

如代碼所示，在這個Feign Client中，我們引用了配置類MultipartSupportConfig ，在MultipartSupportConfig 中，我們實例化了SpringFormEncoder 。這樣這個Feign Client就能夠上傳啦。

注意點

//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)

接口定義中的注解@RequestPart(value = 'file') 不能寫成@RequestParam(value = 'file'） 。

最好將Hystrix的超時時間設長一點，例如5秒，否則可能文件還沒上傳完，Hystrix就超時了，從而導致客戶端側的報錯。

Feign實現Form表單提交

添加依賴：

<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一個form編碼器，實現支持form表單提交 @Bean public Encoder feignFormEncoder() { return new SpringFormEncoder(new SpringEncoder(messageConverters)); } // 開啟Feign的日志 @Bean public Logger.Level logger() { return Logger.Level.FULL; } }}

調用示例：

@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，此時Feign已能使用Form表單方式提交數據。

Feign GET請求如何構造多參數

假設需請求的URL包含多個參數，例如http://microservice-provider-user/get?id=1&username=張三 ，該如何使用Feign構造呢？我們知道，Spring Cloud為Feign添加了Spring MVC的注解支持，那么我們不妨按照Spring MVC的寫法嘗試一下：

@FeignClient('microservice-provider-user')public interface UserFeignClient { @RequestMapping(value = '/get', method = RequestMethod.GET) public User get0(User user);}

然而，這種寫法并不正確，控制臺會輸出類似如下的異常。

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'}

由異常可知，盡管我們指定了GET方法，Feign依然會使用POST方法發送請求。于是導致了異常。正確寫法如下

方法一[推薦]注意:使用該方法無法使用Fegin的繼承模式

@FeignClient('microservice-provider-user')public interface UserFeignClient { @GetMapping('/get') public User get0(@SpringQueryMap User user);}

方法二[推薦]

@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);}

這是最為直觀的方式，URL有幾個參數，Feign接口中的方法就有幾個參數。使用@RequestParam注解指定請求的參數是什么。

方法三[不推薦]多參數的URL也可使用Map來構建。當目標URL參數非常多的時候，可使用這種方式簡化Feign接口的編寫。

@FeignClient(name = 'microservice-provider-user')public interface UserFeignClient { @RequestMapping(value = '/get', method = RequestMethod.GET) public User get2(@RequestParam Map<String, Object> map);}

在調用時，可使用類似以下的代碼。

public User get(String username, String password) { HashMap<String, Object> map = Maps.newHashMap(); map.put('id', '1'); map.put('username', '張三'); return this.userFeignClient.get2(map);}

注意：這種方式不建議使用。主要是因為可讀性不好，而且如果參數為空的時候會有一些問題，例如map.put('username', null); 會導致服務調用方（消費者服務）接收到的username是'' ，而不是null。

切換為 Okhttp3 提升 QPS 性能優化

加依賴引入okhttp3

<dependency> <groupId>io.github.openfeign</groupId> <artifactId>feign-okhttp</artifactId> <version>${version}</version></dependency>

寫配置

feign: # feign啟用hystrix，才能熔斷、降級 # hystrix: # enabled: true # 啟用 okhttp 關閉默認 httpclient httpclient: enabled: false #關閉httpclient # 配置連接池 max-connections: 200 #feign的最大連接數 max-connections-per-route: 50 #fegin單個路徑的最大連接數 okhttp: enabled: true # 請求與響應的壓縮以提高通信效率 compression: request: enabled: true min-request-size: 2048 mime-types: text/xml,application/xml,application/json response: enabled: true

參數配置

/** * 配置 okhttp 與連接池 * ConnectionPool 默認創建5個線程，保持5分鐘長連接 */@Configuration@ConditionalOnClass(Feign.class)@AutoConfigureBefore(FeignAutoConfiguration.class) //SpringBoot自動配置public class OkHttpConfig { // 默認老外留給你彩蛋中文亂碼，加上它就 OK @Bean public Encoder encoder() { return new FormEncoder(); } @Bean public okhttp3.OkHttpClient okHttpClient() { return new okhttp3.OkHttpClient.Builder() //設置連接超時 .connectTimeout(10, TimeUnit.SECONDS) //設置讀超時 .readTimeout(10, TimeUnit.SECONDS) //設置寫超時 .writeTimeout(10, TimeUnit.SECONDS) //是否自動重連 .retryOnConnectionFailure(true) .connectionPool(new ConnectionPool(10, 5L, TimeUnit.MINUTES)) .build(); }}

以上為個人經驗，希望能給大家一個參考，也希望大家多多支持好吧啦網。如有錯誤或未考慮完全的地方，望不吝賜教。