I am asking this question after a couple of days on research and finding no definitive answer to this question: How do I process multipart form-data requests (clean and nice) with JAX-RS (not servlets) in a vendor agnostic way?
Similar questions asked over the years:
I asked so I could as well share my best findings of a solution that I think could work.
I landed on this blog by Gunther Rotsch. Checkout the GitHub repo I have tested his portable solution out and so far so good. I think it is what I have been looking for. Feel feel to try it out and share your comments.
The JAX-RS resource would look like this:
@POST
@Consumes("multipart/form-data")
public Response postFormData(MultiPartMessage message) {
...
}
And the MessageBodyReader, the entry point of JAXRS integration like this:
@Provider
@Consumes("multipart/form-data")
public class MultiPartMessageBodyReader implements MessageBodyReader<MultiPartMessage> {
private static final Logger LOGGER = LoggerFactory.getLogger(MultiPartMessageBodyReader.class);
@Override
public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
LOGGER.info("isReadable called with type: {} and mediaType: {}", type, mediaType);
return MultiPartMessage.class.isAssignableFrom(type)
&& mediaType.toString().toLowerCase().startsWith("multipart/form-data");
}
@Override
public MultiPartMessage readFrom(Class<MultiPartMessage> type, Type genericType, Annotation[] annotations,
MediaType mediaType, MultivaluedMap<String, String> httpHeaders, InputStream entityStream)
throws IOException, WebApplicationException {
...
}
"The @Provider annotation declares the class to JAXRS, which calls this reader when the de-marshalling of messages of content type multipart/from-data is required."