"multipart config was not present on Servlet" when trying to upload a file with JAX-RS class - file-upload

Question

I have the following JAX-RS class to upload a file from a browser (implemented in Wildfly 14). Problem is I get the error multipart config was not present on Servlet. Since I annotated the class with #Consumes({ MediaType.MULTIPART_FORM_DATA }) I'm not sure what is missing. How to fix this problem?
#Produces({ MediaType.APPLICATION_JSON })
#Consumes({ MediaType.MULTIPART_FORM_DATA })
public class FileUploadService {
#Context
private HttpServletRequest request;
#POST
#Path("/upload")
public Response processUpload() throws IOException, ServletException {
String path = "/mypath";
for (Part part : request.getParts()) {
String fileName = getFileName(part);
String fullPath = path + File.separator + fileName;
// delete file if exists
java.nio.file.Path path2 = FileSystems.getDefault().getPath(fullPath);
Files.deleteIfExists(path2);
// get file input stream
InputStream fileContent = part.getInputStream();
byte[] buffer = new byte[fileContent.available()];
fileContent.read(buffer);
File targetFile = new File(fullPath);
// write output file
OutputStream outStream = new FileOutputStream(targetFile);
outStream.write(buffer);
outStream.close();
}
return Response.ok("OK").build();
}
private String getFileName(Part part) {
for (String content : part.getHeader("content-disposition").split(";")) {
if (content.trim().startsWith("filename"))
return content.substring(content.indexOf("=") + 2, content.length() - 1);
}
return "";
}
}