How to get raw binary data from a POST request processed by Spring?

It's as easy as declaring an InputStream in your controller method's parameters:

@RequestMapping(method = RequestMethod.POST, value = "/data")public void acceptData(InputStream dataStream) throws Exception {    processText(dataStream);}

You shouldn't need to disable HiddenHttpMethodFilter, if you do it's probably that your request is wrong in some way. See https://github.com/spring-projects/spring-boot/issues/5676.

I was able to resolve this using the following code:

@Beanpublic FilterRegistrationBean registration(HiddenHttpMethodFilter filter) {    FilterRegistrationBean registration = new FilterRegistrationBean(filter);    registration.setEnabled(false);    return registration;}@RequestMapping(method = RequestMethod.POST, value = "/data")public void acceptData(HttpServletRequest requestEntity) throws Exception {    byte[] processedText = IOUtils.toByteArray(requestEntity.getInputStream());    processText(processedText);}

Spring does pre-processing by default, which causes the HttpServletRequest to be empty by the time it reaches the RequestMapping. Adding the FilterRegistrationBean Bean solves that issue.