微服务架构的拆分，各模块之间使用feign组件来进行相互http转发通信。
前端与后端之间使用springcloud的网关来进行协调。
现在问题出现，用户的信息如何进行传递？
前端请求携带请求头，请求头中的authorization为携带的对应token，这个token如何转发给各个微服务模块？
具体流程：前端发送请求->网关进行解析->从springcloud拦截器的exchange.header中解析出token->将token写入到新的exchange.header中，并且命名为info，这个exchange会被向后传递（因为本身springcloud就有多个拦截器，该拦截器处理完之后会传递给下一个拦截器 ）->根据网关解析的端口号，发送request到对应端口的微服务中->微服务的拦截器对request进行拦截(实际上是一个共有模块，各个微服务依赖于这个模块，所以其网络请求会被该模块拦截)->读取传递过来请求头中的info信息，存入threadLocal中。
1.由于所有前端请求都会到达springcloud的拦截器，并且拦截器有多个，只需在拦截器中将需要传递的“info”存进网络请求中，对应的拦截器定义如下：
package com.hxy.hmgateway.filter;import com.hxy.hmgateway.config.AuthProperties;
import com.hxy.hmgateway.utils.JwtTool;
import lombok.RequiredArgsConstructor;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;import java.util.List;@Component
@RequiredArgsConstructor
public class AuthGlobalFilter implements GlobalFilter, Ordered {private final AuthProperties authProperties;private final JwtTool jwtTool;private final AntPathMatcher antPathMatcher = new AntPathMatcher();@Overridepublic Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {ServerHttpRequest request = exchange.getRequest();//放行排除路径String path = request.getPath().toString();if(isExclude(path,authProperties.getExcludePaths())){return chain.filter(exchange);}//1.获取tokenHttpHeaders headers = request.getHeaders();List<String> tokenList = headers.get("authorization");//2.判别token是否为空String token = null;if (tokenList!=null && !tokenList.isEmpty()){token = tokenList.get(0);}//3.获取userIdLong userId = null;//4.判别token是否正确try {userId = jwtTool.parseToken(token);} catch (Exception e) {ServerHttpResponse response = exchange.getResponse();response.setStatusCode(HttpStatus.UNAUTHORIZED);return response.setComplete();}//TODO userId的转发System.out.println("userId:"+userId);String userInfo = String.valueOf(userId);ServerWebExchange swe = exchange.mutate().request(builder ->builder.header("info", userInfo)).build();//5.放行return chain.filter(swe);}private boolean isExclude(String path, List<String> excludePaths) {for (String pathPattern : excludePaths) {if(antPathMatcher.match(pathPattern, path)) return true;}return false;}@Overridepublic int getOrder() {return 0;}
}
注意这里的exchange.mutate指令用于将info存储在网络请求中。
2.该拦截器经过springcloud网关转发后，首先到达所有微服务公共依赖的模块，这个模块会使用springmvc拦截器，用于拦截，info，并将其存入threadlocal中。代码如下；
package com.hmall.common.intercepter;import com.hmall.common.utils.UserContext;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class UserInfoInterceptor implements HandlerInterceptor {@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {String info = request.getHeader("info");if (info == null) return true;Long userId = Long.valueOf(info);UserContext.setUser(userId);return true;}@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {UserContext.removeUser();}
}
package com.hmall.common.config;import com.hmall.common.intercepter.UserInfoInterceptor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.context.annotation.Configuration;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.servlet.config.annotation.InterceptorRegistration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;@Configuration
@ConditionalOnClass(DispatcherServlet.class)
public class MvcConfig implements WebMvcConfigurer {@Overridepublic void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(new UserInfoInterceptor());}
}
为了使得其余微服务能够扫描到该共有模块的包，需要将拦截器对应的包添加在如下文件中：
对应的spring.factories文件如下：
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\com.hmall.common.config.MyBatisConfig,\com.hmall.common.config.MvcConfig,\com.hmall.common.config.JsonConfig最后需要注意，在mvc配置文件中，添加了一个注解
ConditionalOnClass，用于标记仅对使用了该类的模块生效
》题集)
