Gediminas Rimsa created LOGBACK-1503: ---------------------------------------- Summary: TeeFilter breaks multipart processing on Spring Boot 2.2+ Key: LOGBACK-1503 URL: https://jira.qos.ch/browse/LOGBACK-1503 Project: logback Issue Type: Bug Components: logback-access Affects Versions: 1.2.3 Environment: Spring Boot 2.2.4, Tomcat 9.0.30, Logback 1.2.3   TeeFilter registered like this: {{ {color:#808000}@Bean {color} {color:#000080}public {color}FilterRegistrationBean<TeeFilter> requestResponseFilter2() \{}} {{    FilterRegistrationBean<TeeFilter> filterRegBean = {color:#000080}new {color}FilterRegistrationBean<>();}} {{    filterRegBean.setFilter({color:#000080}new {color}TeeFilter());}} {{    filterRegBean.setName({color:#008000}"Logback access-logging request response filter"{color});}} {{    {color:#000080}return {color}filterRegBean;}} {{ }}} Reporter: Gediminas Rimsa Assignee: Logback dev list Priority: Minor *Symptom* Webapp fails to process multipart HTTP requests with the following exception: {quote} org.springframework.web.multipart.MultipartException: Failed to parse multipart servlet request; nested exception is java.io.IOException: org.apache.tomcat.util.http.fileupload.FileUploadException: Stream closed {quote} *Troubleshooting* - Multipart requests work when TeeFilter is disabled. - Multipart requests work when Spring Boot is downgraded to 2.1.12 (Tomcat still 9.0.30, Logback still 1.2.3) *Root cause* `TeeFilter` decorates incoming request with `TeeHttpServletRequest` that reads the input stream and closes it (see `TeeServletInputStream#duplicateInputStream`). Everything works as expected here. However, when `HttpServletRequest#getParts` is called later, `TeeHttpServletRequest` delegates it to the original request, which has its stream closed already, which results in the exception. *Workaround* Force loading of parts before request passes through `TeeFilter`. With Tomcat this is as simple as: {{{color:#000080}private static class {color}MultipartSafeTeeFilter {color:#000080}extends {color}TeeFilter \{}} {{    {color:#808000}@Override {color}    {color:#000080}public void {color}doFilter(}} {{        ServletRequest request,}} {{        ServletResponse response,}} {{        FilterChain filterChain}} {{    ) {color:#000080}throws {color}IOException, ServletException \{}} {{        request.getParameter({color:#008000}"whatever"{color});}} {{        {color:#000080}super{color}.doFilter(request, response, filterChain);}} {{    }}} {{}}}   -- This message was sent by Atlassian JIRA (v7.3.1#73012)