Multipart/form-data construction with android

Question

I am trying to make an HttpPost with multiPart/form-data via my android app. I have a postman test that is working with my api and the preview of that request in postman, looks like this:

POST /api/0.1/content/upload HTTP/1.1
Host: 54.221.194.167
X-AUTHORIZATION: 166e649911ff424eb14446cf398bd7d6
Cache-Control: no-cache
Postman-Token: 2412eba9-f72d-6f3b-b124-6070b5b26644

----WebKitFormBoundaryE19zNvXGzXaLvS5C
Content-Disposition: form-data; name="file01"

{"mime_type":"image/jpeg","title":"IMG_20140131_111622"}
----WebKitFormBoundaryE19zNvXGzXaLvS5C
Content-Disposition: form-data; name="file01"; filename="addedaslib.jpg"
Content-Type: image/jpeg


----WebKitFormBoundaryE19zNvXGzXaLvS5C

I am trying to replicate that using the multipart/form-data with my android HttpPost but it doesn't seem to be working. Is there a way to "preview" my request and see how it is actually posting to the api? what am i doing wrong? my code:

public HttpResponse invokeXAUTHPOSTService(String url, String token, File file) {


        client = new DefaultHttpClient();
        HttpPost request = new HttpPost(url);
        HttpResponse response = null; 
        MultipartEntity mpe = new MultipartEntity();
    try {


        Log.v("API", "URL:"+url);
        request.setHeader("Content-Type", "multipart/form-data");
        request.addHeader("X-AUTHORIZATION",token);
        request.addHeader("Cache-Control", "no-cache");

        DRPContentForUpload content = new DRPContentForUpload(file);
        String jsonObject = DRPJSONConverter.toJson(content);

        FormBodyPart part1= new FormBodyPart("file01", new StringBody(jsonObject));
        FormBodyPart part2= new FormBodyPart("file01", new FileBody(file)); 
        mpe.addPart(part1);
        mpe.addPart(part2);

        //

        request.setEntity(mpe);
        Log.v("RAW REQUEST", "request looks like:"+mpe.toString());
        response = client.execute(request);

EDIT

I was able to talk to my API team, and they said my post actually looks like this:

--0ieMJK6PPwcrM_K3KQvl6eNDGqooZPzJcvHOm0
Content-Disposition: form-data; name="file01"
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 8bit

{"mime_type":"image/jpeg","title":"IMG_20140131_111622"}
--0ieMJK6PPwcrM_K3KQvl6eNDGqooZPzJcvHOm0
Content-Disposition: form-data; name="file01"; filename="IMG_20140131_111622.jpg"
Content-Type: application/octet-stream
Content-Transfer-Encoding: binary

That said its still not working and spitting back an error that i am missing params

here is a screen shot of the libraries included in my project:

Beard

Answer 1

So after searching high and low for an answer, and almost giving up, this link finally helped

here is the final working code:

 public HttpResponse invokeXAUTHPOSTService(String url, String token, File file) {

    client = new DefaultHttpClient();

    HttpPost request = new HttpPost(url);

    HttpResponse response = null;

    DRPContentForUpload content = new DRPContentForUpload(file);
    String jsonObject = DRPJSONConverter.toJson(content);
    String BOUNDARY= "--eriksboundry--";

    request.setHeader("Content-Type", "multipart/form-data; boundary="+BOUNDARY);
    request.addHeader("X-AUTHORIZATION",token);
    MultipartEntity entity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE,BOUNDARY,Charset.defaultCharset());
    try {


        entity.addPart("file01", new StringBody(jsonObject));

        entity.addPart("file01", new FileBody(file));

        request.addHeader("Accept-Encoding", "gzip, deflate");

    } catch (UnsupportedEncodingException e) {
        Log.v("encoding exception","E::: "+e);
        e.printStackTrace();
    }
    request.setHeader("Accept", "application/json");
    request.setHeader("Content-Type", "multipart/form-data; boundary="+BOUNDARY);
    request.setEntity(entity);

    try {




        response = client.execute(request);



    } catch (ClientProtocolException e) {

        e.printStackTrace();
    } catch (IOException e) {

        e.printStackTrace();
    }


    return response;

}

Beard

You can as well use official httpclient port for Android hc.apache.org/httpcomponents-client-4.3.x/android-port.html – Tenpin

what is BOUNDARY for? – Valenta

Answer 2

Is the problem that the mime-type for your image isn't being set properly? Try to use the alternative constructor for FileBody:

FormBodyPart part2 = new FormBodyPart("file01", new FileBody(file, "image/jpeg"));

Giving both parts of the multi-part request the same name is a bit suspicious, but it doesn't seem to be causing you problems here.

If you want to see what your body looks like before sending, try using EntityUtils.toString(Entity) on the multi-part entity after adding all of the elements. The image is simply binary so won't print very well, but the headers should be readable.

Acaroid