java - 使用 Spring Rest 模板 + Spring Web MVC 进行多部分文件上传

Question

我正在尝试使用带有以下代码的 RestTemplate 上传文件。

   MultiValueMap<String, Object> multipartMap = new LinkedMultiValueMap<>();
   multipartMap.add("file", new ClassPathResource(file));

   HttpHeaders headers = new HttpHeaders();
   headers.setContentType(new MediaType("multipart", "form-data"));

   HttpEntity<MultiValueMap<String, Object>> request = new HttpEntity<MultiValueMap<String, Object>>(multipartMap, headers);

   System.out.println("Request for File Upload : " + request);

   ResponseEntity<byte[]> result = template.get().exchange(
                    contextPath.get() + path, HttpMethod.POST, request,
                    byte[].class);

我有 MultipartResolver bean 和 Controller 代码是

@RequestMapping(value = "/{id}/image", method = RequestMethod.POST)
@ResponseStatus(HttpStatus.NO_CONTENT)
@Transactional(rollbackFor = Exception.class)
public byte[] setImage(@PathVariable("id") Long userId,
        @RequestParam("file") MultipartFile file) throws IOException {
    // Upload logic
}

我得到以下异常

 org.springframework.web.bind.MissingServletRequestParameterException: Required MultipartFile parameter 'file' is not present
        at org.springframework.web.method.annotation.RequestParamMethodArgumentResolver.handleMissingValue(RequestParamMethodArgumentResolver.java:255) ~[spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:95) ~[spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:79) ~[spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:157) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:124) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:863) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:646) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837) [spring-webmvc-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.springframework.web.filter.ShallowEtagHeaderFilter.doFilterInternal(ShallowEtagHeaderFilter.java:80) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.logging.log4j.web.Log4jServletFilter.doFilter(Log4jServletFilter.java:67) [log4j-web-2.0.2.jar:2.0.2]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:154) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at m.m.m.AbstractPreAuthenticatedProcessingFilter.doFilter(UapAbstractPreAuthenticatedProcessingFilter.java:109) [classes/:?]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:50) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160) [spring-security-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
        at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:344) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:261) [spring-web-4.0.6.RELEASE.jar:4.0.6.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [?:1.7.0_67]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [?:1.7.0_67]
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-7.0.54.jar:7.0.54]
        at java.lang.Thread.run(Thread.java:745) [?:1.7.0_67]

Answer 1

在使用 RestTemplate 对 Upload 进行以下代码修改后，Multipart File Upload 起作用了

LinkedMultiValueMap<String, Object> map = new LinkedMultiValueMap<>();
map.add("file", new ClassPathResource(file));
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.MULTIPART_FORM_DATA);

HttpEntity<LinkedMultiValueMap<String, Object>> requestEntity = new    HttpEntity<LinkedMultiValueMap<String, Object>>(
                    map, headers);
ResponseEntity<String> result = template.get().exchange(
                    contextPath.get() + path, HttpMethod.POST, requestEntity,
                    String.class);

并将 MultipartFilter 添加到 web.xml

    <filter>
        <filter-name>multipartFilter</filter-name>
        <filter-class>org.springframework.web.multipart.support.MultipartFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>multipartFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>