使用OpenFeign远程调用时请求头处理报错问题

1. 错误信息



basic.result.exception.OtherException: feign error:系统异常:Content type 'multipart/form-data;boundary=--------------------------679449061975336133574827;charset=UTF-8' not supported.请联系管理员

	at com.assembly.oauth.web.exception.auth.FeignErrorDecoder.decode(FeignErrorDecoder.java:26)

	at feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:149)

	at feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:78)

	at feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:103)

	at com.sun.proxy.$Proxy191.addStationModelList(Unknown Source)

	at com.assembly.dg.online.controller.TestController.importStation(TestController.java:326)

	at com.assembly.dg.online.controller.TestController$$FastClassBySpringCGLIB$$1.invoke(<generated>)

	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)

	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:684)

	at com.assembly.dg.online.controller.TestController$$EnhancerBySpringCGLIB$$1.importStation(<generated>)

	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

	at java.lang.reflect.Method.invoke(Method.java:498)

	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:189)

	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)

	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)

	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)

	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800)

	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)

	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038)

	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)

	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)

	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)

	at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)

	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)

	at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)

	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)

	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

	at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:90)

	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

	at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:117)

	at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:106)

	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)

	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

	at com.assembly.oauth.web.authorization.interceptor.CrossFilter.doFilter(CrossFilter.java:57)

	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)

	at org.apache.catalina.core.StandardContextValve.__invoke(StandardContextValve.java:96)

	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:41002)

	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)

	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)

	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)

	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)

	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668)

	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)

	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)

	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)

	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:834)

	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1417)

	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)

	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)

	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)

	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

	at java.lang.Thread.run(Thread.java:748)

2. 使用场景以及问题出现的原因

在本地微服务中使用Spring MVC 上传文件时, 因为使用了MultipartFile 对象接受, 所以前端设置请求头"Content-type"为multipart/form-data; ,这在本地微服务中是没有问题的,

但是在处理请求的过程中, 使用了OpenFeign 远程调用了其他的微服务保存信息, 就有问题了,

@RequestMapping(value = "importStation")

    @NoAuthorization

    public void importStation(MultipartFile file, HttpServletRequest request) throws IOException {

        // ... 业务处理

        // RPC远程调用 保存信息

        dgRpcRemote.addStationModelList(stationModelList);

    }

本项目中使用的是OpenFeign进行远程调用, 为了在调用时,可以携带调用方的请求头信息,例如token等等, 项目中自定义了一个拦截器进行处理:

@Component

public class FeignBasicAuthRequestInterceptor implements RequestInterceptor {

    public FeignBasicAuthRequestInterceptor() {

    }

    public void apply(RequestTemplate requestTemplate) {

        try {

            //获取 ThreadLocal中的 本地Request对象

            ServletRequestAttributes attributes = (ServletRequestAttributes)RequestContextHolder.getRequestAttributes();

            if (attributes == null) {

                return;

            }

            HttpServletRequest request = attributes.getRequest();

            Enumeration<String> headerNames = request.getHeaderNames();

            String type;

            String tenantCode;

            if (headerNames != null) {

                // 全盘拷贝过去

                while(headerNames.hasMoreElements()) {

                    type = (String)headerNames.nextElement();

                    tenantCode = request.getHeader(type);

                    requestTemplate.header(type, new String[]{tenantCode});

                }

            }

            type = TenantContextHolder.getAuthorizationType();

            if (StringUtils.isNotBlank(type)) {

                requestTemplate.header("tenantAuthorization", new String[]{type});

            }

            tenantCode = TenantContextHolder.getTenantCode();

            if (StringUtils.isNotBlank(tenantCode)) {

                requestTemplate.header("tenantCode", new String[]{tenantCode});

            }

            String tokenId = TenantContextHolder.getTokenId();

            if (StringUtils.isNotBlank(tokenId)) {

                requestTemplate.header("tenantToken", new String[]{tokenId});

            }

            requestTemplate.header("Content-Type", new String[]{"application/json;charset=UTF-8"});

        } catch (Exception var8) {

            var8.printStackTrace();

        }

    }

}

只需实现接口RequestInterceptor 并被Spring扫描到即可,OpenFeign会自动调用,此类重写的 apply 方法中就将本地的请求Request对象的请求头全部拷贝到新的请求中用于调用,这样multipart/form-data; 也就拷贝了过去,但是在RPC 调用的接受方,确只是普通的 Rest 接口, 需要的是application/json ,所以就报了上述错误.

如果项目中在使用Feign进行远程调用,并有需要进行请求头传递的需求,可以参考此方式

3. 解决方式

因为在拦截器中获取的是 ThreadLocal 中保存的本地请求Request 信息,所以只需保证在调用时不在请求所在线程即可:

new Thread(() ->dgRpcRemote.addStationModelList(stationModelList) ).start();

在调用时另启动一个线程进行调用即可, 如果有更好的方式,欢迎指教