Spring MVC: Handling Multi-Part Form Data with File Uploads and JSON Payloads
I'm stuck trying to I'm building a feature where I'm relatively new to this, so bear with me. I'm currently working on a Spring MVC application and I need to handle a multi-part form submission that includes both file uploads and JSON data. My form allows users to upload a profile picture along with their personal details in JSON format. However, I'm working with an scenario where the JSON data is not being correctly parsed when the form is submitted. Here's a snippet of my HTML form: ```html <form action="/api/profile" method="post" enctype="multipart/form-data"> <input type="file" name="profilePicture"/> <textarea name="userDetails">{"name":"John Doe","email":"john@example.com"}</textarea> <button type="submit">Upload</button> </form> ``` On the server side, I have a controller that looks like this: ```java @PostMapping(value = "/api/profile", consumes = {MediaType.MULTIPART_FORM_DATA_VALUE}) public ResponseEntity<String> uploadProfile(@RequestParam("profilePicture") MultipartFile file, @RequestParam("userDetails") String userDetails) { // Parsing the JSON data ObjectMapper objectMapper = new ObjectMapper(); UserDetails user; try { user = objectMapper.readValue(userDetails, UserDetails.class); } catch (JsonProcessingException e) { return ResponseEntity.badRequest().body("behavior parsing JSON: " + e.getMessage()); } // Additional processing... return ResponseEntity.ok("Profile updated successfully"); } ``` Despite using `@RequestParam` to retrieve both the file and JSON data, I keep getting a `400 Bad Request` behavior, and the behavior message indicates that the JSON want to be parsed correctly. When I debug, the `userDetails` parameter appears empty. I've tried adding `@RequestPart` instead of `@RequestParam`, which leads to a similar scenario. Additionally, I've verified that the form is correctly using `enctype="multipart/form-data"`, and the file upload works fine when tested independently. Could there be a specific scenario with how Iām structuring the JSON in the form or a configuration question with Spring MVC? Any insights or suggestions to resolve this would be greatly appreciated! I'm working on a API that needs to handle this. What's the best practice here? The project is a microservice built with Java. Am I missing something obvious? The stack includes Java and several other technologies.