Writing Wrapper for FileUpload in Spring boot : File not Present - spring-boot

Question

Use Case
I need to write a wrapper for a FileUpload API, which takes Files from UI, and upload those to remote API. What I have chalked out so far:
Made a Controller which takes File and Content body as Request part, then I try to upload them to remote API, code snippets follow:
Controller Endpoint
ResponseEntity uploadFiles(#RequestPart("files") MultipartFile[] files, #RequestPart("someData") Metadata fileMetadata)
File Upload Code
byte[][] fileArray = Arrays.stream(files).map(multipartFile -> {
try {
return multipartFile.getBytes();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}).toArray(byte[][]::new);
//add file
LinkedMultiValueMap<String, Object> params = new LinkedMultiValueMap<>();
configuration.getDocumentCategory());
params.add(DocStorageConstants.FILE, fileArray);
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.MULTIPART_FORM_DATA);
HttpEntity<LinkedMultiValueMap<String, Object>> requestEntity = new HttpEntity<>(params, headers);
ResponseEntity<FileUploadResponse> responseEntity = restTemplate.postForEntity(configuration.getUploadEndpoint(), requestEntity, FileUploadResponse.class);
The remote API returns response as if Files never reached this API, what I need to do to avoid this? I might try writing file to a temporary file and then upload that file to remote endpoint, not sure if that is a clean approach. Thanks in advance for any suggestions!
[Update]: The cURL that I am trying to form is below:
curl --location --request POST 'http://<host>:<port>/file-endpoint' \
--header 'X-Api-Client:<api-key>' \
--header 'x-service-id: <service-id>' \
--form 'file=#"/aggregate.csv"' \
--form 'uploadRequest="{\"bn\":\"NFA\",\"dc\":\"generalDocs\",
\"tags\":[\"test\", \"test2\"]
}"'

Answer 1

Following snippet worked
Arrays.stream(files).forEach(multipartFile -> params.add(DocStorageConstants.FILE, multipartFile.getResource()));