Upload files Android (react-native)

I am upgrading a react-native project (from 0.43.1 -> 0.61.4 ) This is a project with a backend in place, the project uses react-native-fileupload ( A really old library ).

I forked this and updated the iOS version ( just changed the imports ) and got it working again straight away. But the Android version won't work, in my opinion the java code looks ok, but obviously not since it isn't working.

The error I get is 403, without any message ( I don't have access directly to the server ), but since I can see the iOS request get through with the same request body and auth method. I don't know if it might be anything to do with headers or imports since this now also runs 64 bit instead of earlier 32.

The files is image (jpeg) and audio (aac). And I see the code running all the way down to the response without breaking.

Forked library code: https://github.com/PhilippKrone/react-native-fileupload

Android code:

package com.yoloci.fileupload;

import android.os.Bundle;

import com.facebook.react.bridge.Arguments;
import com.facebook.react.bridge.ReadableArray;
import com.facebook.react.bridge.ReadableMap;
import com.facebook.react.bridge.ReadableMapKeySetIterator;
import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import com.facebook.react.bridge.Callback;

import java.io.DataInputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.io.DataOutputStream;
import java.io.BufferedReader;
import java.io.InputStreamReader;

import com.facebook.react.bridge.WritableMap;
import java.io.FileInputStream;

import org.json.JSONObject;

public class FileUploadModule extends ReactContextBaseJavaModule {

    @Override
    public String getName() {
        return "FileUpload";
    }

    public FileUploadModule(ReactApplicationContext reactContext) {
        super(reactContext);
    }

    @ReactMethod
    public void upload(final ReadableMap options, final Callback callback) {
        String lineEnd = "\r\n";
        String twoHyphens = "--";
        String boundary =  "*****";

        String uploadUrl = options.getString("uploadUrl");
        String method;
        if (options.hasKey("method")) {
            method = options.getString("method");
        } else {
            method = "POST";
        }

        ReadableMap headers = options.getMap("headers");
        ReadableArray files = options.getArray("files");
        ReadableMap fields = options.getMap("fields");



        HttpURLConnection connection = null;
        DataOutputStream outputStream = null;
        DataInputStream inputStream = null;
        URL connectURL = null;
        FileInputStream fileInputStream = null;

        int bytesRead, bytesAvailable, bufferSize;
        byte[] buffer;
        int maxBufferSize = 1*1024*1024;

        try {
            connectURL = new URL(uploadUrl);
            connection = (HttpURLConnection) connectURL.openConnection();
            // Allow Inputs & Outputs.
            connection.setDoInput(true);
            connection.setDoOutput(true);
            connection.setUseCaches(false);

            connection.setRequestMethod(method);

            // set headers
            ReadableMapKeySetIterator iterator = headers.keySetIterator();
            while (iterator.hasNextKey()) {
                String key = iterator.nextKey();
                connection.setRequestProperty(key, headers.getString(key));
            }



            connection.setRequestProperty("Connection", "Keep-Alive");
            connection.setRequestProperty("Content-Type", "multipart/form-data;boundary="+boundary);

            outputStream = new DataOutputStream( connection.getOutputStream() );

            // set fields
            ReadableMapKeySetIterator fieldIterator = fields.keySetIterator();
            while (fieldIterator.hasNextKey()) {
                outputStream.writeBytes(twoHyphens + boundary + lineEnd);

                String key = fieldIterator.nextKey();
                outputStream.writeBytes("Content-Disposition: form-data; name=\"" + key +  "\"" + lineEnd + lineEnd);
                outputStream.writeBytes(fields.getString(key));
                outputStream.writeBytes(lineEnd);
            }


            for (int i = 0; i < files.size(); i++) {

                ReadableMap file = files.getMap(i);
                String filename = file.getString("filename");
                String filepath = file.getString("filepath");
                filepath = filepath.replace("file://", "");
                fileInputStream = new FileInputStream(filepath);

                outputStream.writeBytes(twoHyphens + boundary + lineEnd);
                outputStream.writeBytes("Content-Disposition: form-data; name=\"image\";filename=\"" + filename + "\"" + lineEnd);
                outputStream.writeBytes(lineEnd);

                bytesAvailable = fileInputStream.available();
                bufferSize = Math.min(bytesAvailable, maxBufferSize);
                buffer = new byte[bufferSize];

                // Read file
                bytesRead = fileInputStream.read(buffer, 0, bufferSize);

                while (bytesRead > 0) {
                    outputStream.write(buffer, 0, bufferSize);
                    bytesAvailable = fileInputStream.available();
                    bufferSize = Math.min(bytesAvailable, maxBufferSize);
                    bytesRead = fileInputStream.read(buffer, 0, bufferSize);
                }

                outputStream.writeBytes(lineEnd);
            }

            outputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);

            // Responses from the server (code and message)

            int serverResponseCode = connection.getResponseCode();
            String serverResponseMessage = connection.getResponseMessage();
            if (serverResponseCode != 200) {
                fileInputStream.close();
                outputStream.flush();
                outputStream.close();
                callback.invoke("Error happened: " + serverResponseMessage, null);
            } else {
                BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
                StringBuilder sb = new StringBuilder();
                String line;
                while ((line = br.readLine()) != null) {
                    sb.append(line);
                }
                br.close();
                String data = sb.toString();
                JSONObject mainObject = new JSONObject();
                mainObject.put("data", data);
                mainObject.put("status", serverResponseCode);

                BundleJSONConverter bjc = new BundleJSONConverter();
                Bundle bundle = bjc.convertToBundle(mainObject);
                WritableMap map = Arguments.fromBundle(bundle);

                fileInputStream.close();
                outputStream.flush();
                outputStream.close();
                callback.invoke(null, map);
            }



        } catch(Exception ex) {
            callback.invoke("Error happened: " + ex.getMessage(), null);
        }
    }
}

I noticed the code:

  outputStream.writeBytes("Content-Disposition: form-data; name=\"image\";filename=\"" + filename + "\"" + lineEnd);

saying image but It didn't do any difference changing it to dynamically adjust.

Any input would really help me out, thanks in advance!