实现思路:
1:准备一个ThreadLocal变量,供线程之间共享。
2:每个微服务对所有过来的Feign调用进行过滤,然后从请求头中获取User用户信息,并存在ThreadLocal变量中。
3:每个微服务在使用FeignClient调用别的微服务时,先从ThreadLocal里面取出user信息,并放在request的请求头中。
4:封装为一个注解,在启动类上标记即可。
代码样例:
1:ThreadLocal工具类 :UserInfoContext
package com.test.domi.common.system; import com.test.domi.dao.UserInfo; public class UserInfoContext { private static ThreadLocaluserInfo = new ThreadLocal (); public static String KEY_USERINFO_IN_HTTP_HEADER = "X-AUTO-FP-USERINFO"; public UserInfoContext() { } public static UserInfo getUser(){ return (UserInfo)userInfo.get(); } public static void setUser(UserInfo user){ userInfo.set(user); } }
2:准备承载用户信息的userInfo实体类(代码略)
3:编写拦截器 : TransmitUserInfoFeighClientIntercepter
package com.test.domi.config; import com.alibaba.fastjson.JSON; import com.test.domi.common.system.UserInfoContext; import com.test.domi.dao.UserInfo; import feign.RequestInterceptor; import feign.RequestTemplate; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; public class TransmitUserInfoFeighClientIntercepter implements RequestInterceptor { private static final Logger log = LoggerFactory.getLogger(TransmitUserInfoFeighClientIntercepter.class); public TransmitUserInfoFeighClientIntercepter() { } @Override public void apply(RequestTemplate requestTemplate) { //从应用上下文中取出user信息,放入Feign的请求头中 UserInfo user = UserInfoContext.getUser(); if (user != null) { try { String userJson = JSON.toJSONString(user); requestTemplate.header("KEY_USERINFO_IN_HTTP_HEADER",new String[]{URLDecoder.decode(userJson,"UTF-8")}); } catch (UnsupportedEncodingException e) { log.error("用户信息设置错误",e); } } } }
4:编写过滤器:TransmitUserInfoFilter
package com.test.domi.config; import com.alibaba.fastjson.JSON; import com.test.domi.common.system.UserInfoContext; import com.test.domi.dao.UserInfo; import org.apache.commons.lang.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.servlet.*; import javax.servlet.http.HttpServletRequest; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; public class TransmitUserInfoFilter implements Filter { private static final Logger log = LoggerFactory.getLogger(TransmitUserInfoFeighClientIntercepter.class); public TransmitUserInfoFilter() { } @Override public void init(FilterConfig filterConfig) throws ServletException { } @Override public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { this.initUserInfo((HttpServletRequest)request); chain.doFilter(request,response); } private void initUserInfo(HttpServletRequest request){ String userJson = request.getHeader("KEY_USERINFO_IN_HTTP_HEADER"); if (StringUtils.isNotBlank(userJson)) { try { userJson = URLDecoder.decode(userJson,"UTF-8"); UserInfo userInfo = (UserInfo) JSON.parseObject(userJson,UserInfo.class); //将UserInfo放入上下文中 UserInfoContext.setUser(userInfo); } catch (UnsupportedEncodingException e) { log.error("init userInfo error",e); } } } @Override public void destroy() { } }
5:编写注解实现类: EnableUserInfoTransmitterAutoConfiguration
package com.test.domi.config; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; @Configuration public class EnableUserInfoTransmitterAutoConfiguration { public EnableUserInfoTransmitterAutoConfiguration() { } @Bean public TransmitUserInfoFeighClientIntercepter transmitUserInfo2FeighHttpHeader(){ return new TransmitUserInfoFeighClientIntercepter(); } @Bean public TransmitUserInfoFilter transmitUserInfoFromHttpHeader(){ return new TransmitUserInfoFilter(); } }
6:编写注解 EnableUserInfoTransmitter
package com.test.domi.annotation; import com.test.domi.config.EnableUserInfoTransmitterAutoConfiguration; import org.springframework.context.annotation.Import; import java.lang.annotation.*; @Documented @Target({ElementType.TYPE}) @Retention(RetentionPolicy.RUNTIME) @Import({EnableUserInfoTransmitterAutoConfiguration.class}) public @interface EnableUserInfoTransmitter { }
7:在启动类上标记注解即可使用(无侵入)
package com.test.domi; import com.test.domi.annotation.EnableUserInfoTransmitter; import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.discovery.EnableDiscoveryClient; @EnableDiscoveryClient @SpringBootApplication @MapperScan("com.test.domi.dao") @EnableUserInfoTransmitter public class TestCommonClient { public static void main(String[] args){ SpringApplication.run(TestCommonClient.class,args); } }