Submitting MultipartEntity using HttpURLConnection

Question

using the code below, I can send a large file to the server, but I can’t find how to send the text with the file (send the file plus additional data (username, password ..) for an example). and also get it on the server side.

FileInputStream fileInputStream = new FileInputStream(new File(
                   pathToOurFile));
URL url = new URL(urlServer);
            connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
           connection.setDoOutput(true);
            connection.setUseCaches(false);
            connection.setChunkedStreamingMode(1024);
            // Enable POST method
            connection.setRequestMethod("POST");

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

            outputStream = new DataOutputStream(connection.getOutputStream());
            outputStream.writeBytes(twoHyphens + boundary + lineEnd);
 String connstr = null;

            connstr = "Content-Disposition: form-data; name=\"uploadedVideos\";filename=\""
                    + pathToOurFile + "\"" + lineEnd;
outputStream.writeBytes(connstr);
outputStream.writeBytes(lineEnd);
bytesAvailable = fileInputStream.available();
            bufferSize = Math.min(bytesAvailable, maxBufferSize);
            buffer = new byte[bufferSize];

            // Read file
            bytesRead = fileInputStream.read(buffer, 0, bufferSize);
try {
               while (bytesRead > 0) {
                    try {
                        outputStream.write(buffer, 0, bufferSize);
                    } catch (OutOfMemoryError e) {
                        e.printStackTrace();
                        response = "outofmemoryerror";
                        return response;
                    }
                    bytesAvailable = fileInputStream.available();
                    bufferSize = Math.min(bytesAvailable, maxBufferSize);
                    bytesRead = fileInputStream.read(buffer, 0, bufferSize);
                }
            } catch (Exception e) {
                e.printStackTrace();
                response = "error";
                return response;
            }
            outputStream.writeBytes(lineEnd);
            outputStream.writeBytes(twoHyphens + boundary + twoHyphens
                    + lineEnd);
       fileInputStream.close();
        outputStream.flush();
        outputStream.close();

server part:

HttpPostedFile file = HttpContext.Current.Request.Files[0];
string fname = Path.GetFileName(file.FileName);
   file.SaveAs(Server.MapPath(Path.Combine("~/UploadedVideos/" + Date  + "/", fname)));

Please any help would be greatly appreciated. I know I can do this with HttpClient, but it does not work for me in case of large files, so I want to use this method.

Answer 1

Use it

  private static String multipost(String urlString, MultipartEntity reqEntity) {

        try {
            URL url = new URL(urlString);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setReadTimeout(10000);
            conn.setConnectTimeout(15000);
            conn.setRequestMethod("POST");
            conn.setUseCaches(false);
            conn.setDoInput(true);
            conn.setDoOutput(true);

            conn.setRequestProperty("Connection", "Keep-Alive");
            conn.addRequestProperty("Content-length", reqEntity.getContentLength()+"");
            conn.addRequestProperty(reqEntity.getContentType().getName(), reqEntity.getContentType().getValue());

            OutputStream os = conn.getOutputStream();
            reqEntity.writeTo(conn.getOutputStream());
            os.close();
            conn.connect();

            if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
                return readStream(conn.getInputStream());
            }

        } catch (Exception e) {
            Log.e("MainActivity", "multipart post error " + e + "(" + urlString + ")");
        }
        return null;
    }

    private static String readStream(InputStream in) {
        BufferedReader reader = null;
        StringBuilder builder = new StringBuilder();
        try {
            reader = new BufferedReader(new InputStreamReader(in));
            String line = "";
            while ((line = reader.readLine()) != null) {
                builder.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return builder.toString();
    }

and here you can set File, username and password as shown below using MultipartEntiry.

 private void uploadMultipartData() throws UnsupportedEncodingException {

        MultipartEntity reqEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
        reqEntity.addPart("fileToUpload", new FileBody(uploadFile));
        reqEntity.addPart("uname", new StringBody("MyUserName"));
        reqEntity.addPart("pwd", new StringBody("MyPassword"));
        String response = multipost(server_url, reqEntity);

        Log.d("MainActivity", "Response :"+response);
    }

. httpmime jar libs.

Answer 2

, , -, ...

package my.com.myapp.utils;

import android.util.Log;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;

/**
 * This utility class provides an abstraction layer for sending multipart HTTP
 * POST requests to a web server.
 * @author www.codejava.net
 *
 */
public class MultipartUtil {
    private final String boundary;
    private static final String LINE_FEED = "\r\n";
    private HttpURLConnection httpConn;
    protected String charset;
    protected OutputStream outputStream;
    protected PrintWriter writer;
    public boolean cancel = false;
    protected boolean last_item_is_file = false;
    public static String LOG_TAG = "MultipartUtil";
    /**
     * This constructor initializes a new HTTP POST request with content type
     * is set to multipart/form-data
     * @param requestURL
     * @param charset
     * @throws IOException
     */
    public MultipartUtil(String requestURL, String charset, Boolean send_auth)
            throws IOException {
        this.charset = charset;

        // creates a unique boundary based on time stamp
        boundary = "===" + System.currentTimeMillis() + "===";

        URL url = new URL(requestURL);
        httpConn = (HttpURLConnection) url.openConnection();
        httpConn.setUseCaches(false);
        httpConn.setDoOutput(true); // indicates POST method
        httpConn.setDoInput(true);
        httpConn.setRequestProperty("Content-Type",
                "multipart/form-data; boundary=" + boundary);
        httpConn.setRequestProperty("User-Agent", "Android submit");
        //addHeaderField("lang", AppConfig.getInstance().language);
        //addHeaderField("country", AppConfig.getInstance().country);
        //User user = AppConfig.getInstance().get_user();
        /*
        if (send_auth && user != null && user.authentication_token != null && !user.authentication_token.equalsIgnoreCase("")) {
            Log.i(LOG_TAG, "user token: "+user.authentication_token);
            addHeaderField("X-User-Email", user.email);
            addHeaderField("X-User-Token", user.authentication_token);
        } else {
            Log.i(LOG_TAG, "not auth / not logged in");
        }
        */
        // httpConn.setRequestProperty("Test", "Bonjour");
    }

    public PrintWriter setup_writer() throws IOException {
        outputStream = httpConn.getOutputStream();
        writer = new PrintWriter(new OutputStreamWriter(outputStream, charset),
                true);
        return writer;
    }

    /**
     * Adds a form field to the request
     * @param name field name
     * @param value field value
     */
    public void addFormField(String name, String value) {
        writer.append("--" + boundary).append(LINE_FEED);
        writer.append("Content-Disposition: form-data; name=\"" + name + "\"")
                .append(LINE_FEED);
        writer.append("Content-Type: text/plain; charset=" + charset).append(
                LINE_FEED);
        writer.append(LINE_FEED);
        writer.append(value).append(LINE_FEED);
        writer.flush();
        last_item_is_file = false;
    }

    /**
     * Adds a upload file section to the request
     * @param fieldName name attribute in <input type="file" name="..." />
     * @param uploadFile a File to be uploaded
     * @throws IOException
     */
    public void addFilePart(String fieldName, File uploadFile)
            throws IOException {
        String fileName = uploadFile.getName();
        writer.append("--" + boundary).append(LINE_FEED);
        writer.append(
                "Content-Disposition: form-data; name=\"" + fieldName
                        + "\"; filename=\"" + fileName + "\"")
                .append(LINE_FEED);
        writer.append(
                "Content-Type: "
                        + URLConnection.guessContentTypeFromName(fileName))
                .append(LINE_FEED);
        writer.append("Content-Transfer-Encoding: binary").append(LINE_FEED);
        writer.append(LINE_FEED);
        writer.flush();

        FileInputStream inputStream = new FileInputStream(uploadFile);
        byte[] buffer = new byte[4096];
        int bytesRead = -1;
        while (!cancel && (bytesRead = inputStream.read(buffer)) != -1) {
            outputStream.write(buffer, 0, bytesRead);
        }
        outputStream.flush();
        inputStream.close();
        if (cancel) {
            writer.close();
            return;
        }

        writer.append(LINE_FEED);
        writer.flush();
        last_item_is_file = true;
    }

    public void addFileStreamPart(String fieldName, String fileName, InputStream inputStream)
            throws IOException {

        writer.append("--" + boundary).append(LINE_FEED);
        writer.append(
                "Content-Disposition: form-data; name=\"" + fieldName
                        + "\"; filename=\"" + fileName + "\"")
                .append(LINE_FEED);
        writer.append(
                "Content-Type: "
                        + URLConnection.guessContentTypeFromName(fileName))
                .append(LINE_FEED);
        writer.append("Content-Transfer-Encoding: binary").append(LINE_FEED);
        writer.append(LINE_FEED);
        writer.flush();

        byte[] buffer = new byte[4096];
        int bytesRead = -1;
        while (!cancel && (bytesRead = inputStream.read(buffer)) != -1) {
            outputStream.write(buffer, 0, bytesRead);
        }

        outputStream.flush();
        inputStream.close();
        if (cancel) {
            writer.close();
            return;
        }

        writer.append(LINE_FEED);
        writer.flush();
        last_item_is_file = true;
    }

    /**
     * Adds a header field to the request.
     * @param name - name of the header field
     * @param value - value of the header field
     */
    public void addHeaderField(String name, String value) {
        httpConn.setRequestProperty(name, value);
        //writer.append(name + ": " + value).append(LINE_FEED).flush();
        //addFormField("headers["+name+"]", value);
        //writer.append(name + ": " + value).append(LINE_FEED).flush();
    }

    public HttpURLConnection finish() throws IOException {

        if (last_item_is_file)
            writer.append(LINE_FEED).flush();
        writer.append("--" + boundary + "--").append(LINE_FEED);
        writer.close();

        return httpConn;
    }

}