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HttpGet in Android/Java with GZip encoding

I am running MVC 4 on my server and to save a bit of data for my users I figured I would enable GZip encoding, to do this I simply used:
(C#)
Response.AddHeader("Content-Encoding", "gzip");
Response.Filter = new GZipStream(Response.Filter, CompressionMode.Compress);
In my android application I use:
(Java)
String response = "";
DefaultHttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
try {
HttpResponse execute = client.execute(httpGet);
InputStream content = execute.getEntity().getContent();
BufferedReader buffer = new BufferedReader(
new InputStreamReader(content));
String s = "";
while ((s = buffer.readLine()) != null) {
response += s;
}
} catch (Exception e) {
e.printStackTrace();
}
return response;
When I use GZip the Java code nuts out and causes GC to run, I was never patient enough to wait for it to return.
When I took off GZip from the server it ran perfectly fine. The function to get the response returns straight away with no problem.
I tried adding this to the java code:
httpGet.addHeader("Accept-Encoding", "gzip");
With no success.
Question is, is there something I'm not getting? Can I not put the response in a stream if it is using GZip? Am I meant to use the stream and uncompress it after?
What am I doing wrong?

Instead of using
DefaultHttpClient client = new DefaultHttpClient();
you can use
ContentEncodingHttpClient client = new ContentEncodingHttpClient();
which is a subclass of DefaultHttpClient and supports GZIP content.
You need Apache HttpClient 4.1 for this.
If you have Apache HttpClient 4.2, you should use
DecompressingHttpClient client = new DecompressingHttpClient();
if you have Apache HttpClient 4.3, you should use the HttpClientBuilder

Parse CSV files from a tornado web service within an Android app

I have Tornado web service which returns a link after creating a CSV file as shown below.
http://10.0.2.2:8000/uploads/16165159GyjFImAYZssLEmn/16165159GyjFImAYZssLEmn.csv
Also I have outputted this URL within the Android application successfully. My question is how to parse the data of this file using the URL shown above. I have tried numerous ways and could not get it done. Can some one please help me to solve this problem. The code I have so far is as follows.
Also I have referred to this post as well, however still no success.
HttpClient httpclient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(modifyURL);
HttpResponse httpResponse = httpclient.execute(httpPost);
responseEntity = httpResponse.getEntity();
transformedImageURL = EntityUtils.toString(responseEntity);
URL url = new URL(transformedImageURL);
InputStream stream = url.openStream();
BufferedInputStream bis = new BufferedInputStream(stream);
ByteArrayBuffer baf = new ByteArrayBuffer(200);
nt current = 0;
while((current - bis.read()) != -1){
baf.append((byte) current);
}
String stockText = new String(baf.toByteArray());
String[] tokens = stockText.split(",");
String testData = tokens[0];
Thank you for your time

uploading files to a dataset in CKAN / datahub.io through a Java client

I am testing the uploading of files to a dataset on CKAN / datahub.io through a Java client of the API.
public String uploadFile()
throws CKANException {
String returned_json = this._connection.MultiPartPost("", "");
System.out.println("r: " + returned_json);
return returned_json;
}
and
protected String MultiPartPost(String path, String data)
throws CKANException {
URL url = null;
try {
url = new URL(this.m_host + ":" + this.m_port + path);
} catch (MalformedURLException mue) {
System.err.println(mue);
return null;
}
String body = "";
HttpClient httpclient = new DefaultHttpClient();
try {
String fileName = "D:\\test.jpg";
FileBody bin = new FileBody(new File(fileName),"image/jpeg");
StringBody comment = new StringBody("Filename: " + fileName);
MultipartEntity reqEntity = new MultipartEntity();
reqEntity.addPart("bin", bin);
reqEntity.addPart("comment", comment);
HttpPost postRequest = new HttpPost("http://datahub.io/api/storage/auth/form/2013-01-24T130158/test.jpg");
postRequest.setEntity(reqEntity);
postRequest.setHeader("X-CKAN-API-Key", this._apikey);
HttpResponse response = httpclient.execute(postRequest);
int statusCode = response.getStatusLine().getStatusCode();
System.out.println("status code: " + statusCode);
BufferedReader br = new BufferedReader(
new InputStreamReader((response.getEntity().getContent())));
String line;
while ((line = br.readLine()) != null) {
body += line;
}
System.out.println("body: " + body);
} catch (IOException ioe) {
System.out.println(ioe);
} finally {
httpclient.getConnectionManager().shutdown();
}
return body;
}
2 responses I get to my POST request:
a 413 error ("request entity too large") when the jpeg I try to upload is 2.83 Mb. This disappears when I shrink the file to a smaller size. Is there a limit to file size uploads?
a 500 error ("internal server error"). This is where I am stuck. It might have to do with the fact that my dataset on datahub.io is not "datastore enabled"? (I see a disabled "Data API" button next to my resource files in the dataset, with a tooltip saying:
"Data API is unavailable for this resource as DataStore is disabled"
=> is it a possible reason for this 500 error? If so, how could I enable it from the client side? (pointers to Python code would be useful!)
Thx!
PS: the dataset I am using for testing purposes: http://datahub.io/dataset/testapi

Only someone with access to the exception log could tell you why the 500 is occurring.
However, I'd check your request is the same as what you'd get from the python client that was written alongside the datastore: https://github.com/okfn/ckanclient/blob/master/ckanclient/init.py#L546
You're sending the "bin" image buffer and "comment" file_key in your multipart request. Note the file_key must be changed for every upload, so add in a timestamp or something. And maybe you need to add in a Content-Type: for the binary.

I have been going through the same kind of troubles as the poster of this question. After quite a bit of trial and error, I came up with a solution to the problem. In my case, I had some control over the CKAN repository that I wanted to upload to. If you don't, your problem might be impossible to solve...
I assume you are using the 1.8 version of CKAN?
First of all, check whether the CKAN repository has been set up to allow file upload and if not, configure it to allow that. This can be done on the server using the steps posted here: http://docs.ckan.org/en/ckan-1.8/filestore.html#local-file-storage
The 413 error that you mentioned should be adressed next. This has to do with the general configuration of the server. In my case, the CKAN was hosted through nginx. I added a "client_max_body_size 100M" line to the nginx.conf file. See this post for instance: http://recursive-design.com/blog/2009/11/18/nginx-error-413-request-entity-too-large/
Then there is only the 500 error left. At the time of this writing, the api documentation of CKAN is still a little immature... It does indeed say that you have to build a request like you have made for file upload. However, this request is just to ask for permission for the file upload. If your credentials check out for file upload (not every user may be allowed to upload files), the response holds an object telling you where to send your file to... Because of the unclear api, you ended up merging these two requests.
The following scenario shows a follow up of two requests to handle the file upload. It might be that some steps in the scenario work out differently in your case, because of a repository that has been set up a little differently. If you get error messages, please be sure to check the response's body for clues!
Here is the authentication request that I used:
String body = "";
String generatedFilename=null;
HttpClient httpclient = new DefaultHttpClient();
try {
// create new identifier for every file, use time
SimpleDateFormat dateFormatGmt = new SimpleDateFormat("yyyyMMMddHHmmss");
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
String date=dateFormatGmt.format(new Date());
generatedFilename=date +"/"+filename;
HttpGet getRequest = new HttpGet(this.CKANrepos+ "/api/storage/auth/form/"+generatedFilename);
getRequest.setHeader(CKANapiHeader, this.CKANapi);
HttpResponse response = httpclient.execute(getRequest);
int statusCode = response.getStatusLine().getStatusCode();
BufferedReader br = new BufferedReader(
new InputStreamReader((response.getEntity().getContent())));
String line;
while ((line = br.readLine()) != null) {
body += line;
}
if(statusCode!=200){
throw new IllegalStateException("File reservation failed, server responded with code: "+statusCode+
"\n\nThe message was: "+body);
}
}finally {
httpclient.getConnectionManager().shutdown();
}
Now, if all goes well, the server responds with a json object holding the parameters to use when doing the actual file upload. In my case, the object looked like:
{file_key:"some-filename-to-use-when-uploading"}
Be sure to check the json object though, as I'm given to understand that there may be custom ckan repositories that require more or different parameters.
These responses can then be used in the actual file upload:
File file = new File("/tmp/file.rdf");
String body = "";
HttpClient httpclient = new DefaultHttpClient();
try {
FileBody bin = new FileBody(file,"application/rdf+xml");
MultipartEntity reqEntity = new MultipartEntity();
reqEntity.addPart("file", bin);
reqEntity.addPart("key", new StringBody(filename));
HttpPost postRequest = new HttpPost(this.CKANrepos+"/storage/upload_handle");
postRequest.setEntity(reqEntity);
postRequest.setHeader(CKANapiHeader, this.CKANapi);
HttpResponse response = httpclient.execute(postRequest);
int statusCode = response.getStatusLine().getStatusCode();
BufferedReader br = new BufferedReader(
new InputStreamReader((response.getEntity().getContent())));
String line;
while ((line = br.readLine()) != null) {
body += line;
}
if(statusCode!=200){
getWindow().showNotification("Upload Statuscode: "+statusCode,
body,
Window.Notification.TYPE_ERROR_MESSAGE);
}
}finally {
httpclient.getConnectionManager().shutdown();
}
as you can see, the file_key property has now been transformed into the simple 'key' property. I don't know why.
This will get your file uploaded. The response to this upload request will hold a json object telling you where the file got uploaded to. edit: actually it seems that my ckan responded with a simple html page to tell me that the file got uploaded... I had to parse the page to confirm that the file was uploaded correctly :(
In my case, the file was at
this.CKANrepos +"/storage/f/"+location
where location is the filename returned in the authentication phase.
In the previous code fragments:
//the location of your ckan repository, including /api and possibly version, e.g.
this.CKANrepos = "http://datahub.io/api/3/";
this.CKANapiHeader="X-CKAN-API-Key";
this.CKANapi = "your ckan api key here";

How to upload data using POST-query?

I have following problem: I'm developing the application which need to authorize on server and upload data from my mobile into it. The server side is ready and works correctly. So, for authorizing I use the following code:
URL url = new URL(VALIDATING_URL);
URLConnection connection=url.openConnection();
connection.setDoOutput(true);
PrintWriter out=new PrintWriter(connection.getOutputStream());
out.print(POST_QUERY_EMAIL+email);
out.print("&");
out.print(POST_QUERY_PASS+password);
out.print("&");
out.print(POST_QUERY_CHANNEL+channel);
out.close();
Scanner in=new Scanner(connection.getInputStream());
StringBuilder result=new StringBuilder();
while (in.hasNextLine()) {
result.append(in.nextLine());
result.append("\n");
}
in.close();
It works correctly, and the application will get needed result if I enter correctly data. So, now I need to upload data into server using POST-query, but I don't know how I can do it. Using HTML forms, video is usually uploaded using 'userfile' variable and will be got from $_FILES array in PHP scipts. How can I upload do it from Java? Can I just print data into PrintStream from InputStream?
Thank you, I hope you can help me

Try this,
public void postData() throws Exception {
HttpClient client = new DefaultHttpClient();
HttpPost httppost = new HttpPost("https://www.xyz.com");
List<NameValuePair> list = new ArrayList<NameValuePair>(1);
list.add(new BasicNameValuePair("name","ABC");
httppost.setEntity(new UrlEncodedFormEntity(list));
HttpResponse r = client.execute(httppost);
}

I would suggest reading this. It shows you how to do a POST with URLConnection and explains what's going on.

Invalid Content-Length is sent to the server?

I'm trying to upload a photo to the popular service Dailybooth via their new API through the method documented here.
The problem is that the server is responding with:
<html><head><title>411 Length Required</title>...
The code I'm using to send this data is here:
// 2: Build request
HttpClient httpclient = new DefaultHttpClient();
SharedPreferences settings = DailyboothShared.getPrefs(DailyboothTakePhoto.this);
String oauth_token = settings.getString("oauth_token", "");
HttpPost httppost = new HttpPost(
"https://api.dailybooth.com/v1/pictures.json?oauth_token=" + oauth_token);
Log.d("upload", "Facebook: " + facebook);
Log.d("upload", "Twitter: " + twitter);
try {
InputStream f = getContentResolver().openInputStream(snap_url);
MultipartEntity entity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
entity.addPart("picture", new InputStreamBody(f, snap_url.getLastPathSegment()));
entity.addPart("blurb", new StringBody(blurb));
entity.addPart("publish_to[facebook]", new StringBody(facebook));
entity.addPart("publish_to[twiter]", new StringBody(twitter));
httppost.setEntity(entity);
HttpResponse response = httpclient.execute(httppost);
Log.d("upload", response.toString());
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode == 200) {
// do something?
} else {
Log.d("upload", "Something went wrong :/");
}
Log.d("upload", EntityUtils.toString(response.getEntity()));
} catch (Exception ex) {
ex.printStackTrace();
}
I've got no idea what I'm doing wrong.

You are using either StringBody and InputStreamBody classes which describe the content of your MultipartEntity. Looking at the sources, StringBody.getContentLength() returns the length of the string, but InputStreamBody always return -1, and I guess this is done for the case you need to upload some data to the server without knowing the size of it, and start uploading while data comes to the stream.
If you want to be able to set the content length then you need to know the size of your stream beforehand, what you can do if that's the case is to set the InputStreamBody that way:
new InputStreamBody(f, snap_url.getLastPathSegment()) {
public long getContentLength() {
return /*your length*/;
}
}
or dump your stream in a byte[] array and pass ByteArrayInputStream to the InputStreamBody, of course doing so you loose the streaming ability as you need to cache your data in memory before sending it over...
As you said you are working on images, are this images File by any chance? If so you also have FileBody that return the correct content-length.