Compressing data with GZipStream in C# and upload it to a webservice - c#

I have an XML data which I would like to compress it using GZipStream and upload it to webservice. I would like to create the gzip file in memory instead of of creating it in local disk. I have tried the following:
public string class1(string url, string xml)
{
byte[] data = Encoding.ASCII.GetBytes(xml);
MemoryStream memory = new MemoryStream();
GZipStream gzip = new GZipStream(memory, CompressionMode.Compress, true);
gzip.Write(data, 0, data.Length);
byte[] zip=memory.ToArray();
HttpWebRequest wReq = (HttpWebRequest)WebRequest.Create(url);
wReq.Method = "POST";
wReq.ContentType = "application/zip";
var reqStream = wReq.GetRequestStream();
reqStream.Write(zip,0,zip.Length);
reqStream.Close();
var wRes = wReq.GetResponse();
var resStream = wRes.GetResponseStream();
var resgzip = new GZipStream(resStream, CompressionMode.Decompress);
var reader = new StreamReader(resgzip);
var textResponse = reader.ReadToEnd();
reader.Close();
resStream.Close();
wRes.Close();
return textResponse;
}
After writing data to webservice the server unzips the file and processess it. While the server decompresses the data an exception is thrown in server "Premature end of file". Please help me in this.

Add below method to convert Stream to MemoryStream
public static MemoryStream Read(Stream stream)
{
MemoryStream memStream = new MemoryStream();
byte[] readBuffer = new byte[4096];
int bytesRead;
while ((bytesRead = stream.Read(readBuffer, 0, readBuffer.Length)) > 0)
memStream.Write(readBuffer, 0, bytesRead);
return memStream;
}
then call as below.
var wRes = wReq.GetResponse();
var memstream = Read(wRes.GetResponseStream());
var resgzip = new GZipStream(memstream, CompressionMode.Decompress);
var reader = new StreamReader(resgzip);
var textResponse = reader.ReadToEnd();

Related

Reading data from System.IO.Stream to text or a file

I am using HttpWebRequest.GetStreamData() to get data from stream and then writing a couple of files in that variable.
Before calling the GetResponse() method on the stream, I need to get the copy of data and put it in text format.
Here's my code snippet
HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);
wr.Method = "POST";
string requestbody = "Some Body Text"
Stream rs = wr.GetRequestStream();
foreach (fragment in Documents).ToList())
{
byte[] requestBytes = System.Text.Encoding.UTF8.GetBytes(requestbody);
rs.Write(requestBytes, 0, requestBytes.Length);
FileStream fileStream = new FileStream(fragment.FilePath, FileMode.Open, FileAccess.Read);
byte[] buffer = new byte[4096];
int bytesRead = 0;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
{
rs.Write(buffer, 0, bytesRead);
}
fileStream.Flush();
fileStream.Close();
fileStream = null;
byte[] trailer = System.Text.Encoding.ASCII.GetBytes("Trailer Text");
rs.Write(trailer, 0, trailer.Length);
}
}
using (StreamReader strm = new StreamReader(rs))
{
string text = strm.ReadToEnd();
}
rs.Close();
rs = null;
The issue is I get error "stream was not readable".
When I check the property rs.canread, it is set to false.
Can anyone help me reading the content of my rs stream.
I have tried a couple of methods but none seems to be working as of now.

c# how to save IO.Stream to MemoryStream and save to PDF file on local folder

I am calling a third party service, which return a pdf file by IO.Stream. I need to change to MemoryStream, and save to a pdf file.
cRequestString = ".....";//You need to set up you own URL here.
//Make the API call
try
{
byte[] bHeaderBytes = System.Text.Encoding.UTF8.GetBytes(GetUserPasswordString()); //user and pa for third party call.
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(cRequestString);
request.Method = WebRequestMethods.Http.Get;
request.PreAuthenticate = true;
request.ContentType = "application/pdf";
request.Accept = "application/pdf";
request.Headers.Add("Authorization", "Basic " + Convert.ToBase64String(bHeaderBytes));
MemoryStream memStream;
WebResponse response = request.GetResponse();
using (Stream stream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(stream))
{
memStream = new MemoryStream();
//read small blocks to show correctly
byte[] buffer = new Byte[1023];
int byteCount;
do
{
byteCount = stream.Read(buffer, 0, buffer.Length);
memStream.Write(buffer, 0, byteCount);
} while (byteCount > 0);
}
memStream.Seek(0, SeekOrigin.Begin);//set position to beginning
return memStream;
}
catch
{
return null;
}
//save MemoryStream to local pdf file
private void SavePDFFile(string cReportName, MemoryStream pdfStream)
{
//Check file exists, delete
if (File.Exists(cReportName))
{
File.Delete(cReportName);
}
using (FileStream file = new FileStream(cReportName, FileMode.Create, FileAccess.Write))
{
byte[] bytes = new byte[pdfStream.Length];
pdfStream.Read(bytes, 0, (int)pdfStream.Length);
file.Write(bytes, 0, bytes.Length);
pdfStream.Close();
}
}
You could do the following.
using (Stream stream = response.GetResponseStream())
using(MemoryStream memStream = new MemoryStream())
{
memStream = new MemoryStream();
stream.CopyTo(memoryStream);
// TODO : Rest of your task
}
More details on Stream.CopyTo on MSDN

Exporting byte[] results to corrupted .zip

I am trying to make a CLR with .NET 2.0 integrated into MS SQL Server 2008. I call an API with and I should receive a .zip as response. I store the response into a Stream and I want to export this file to a physical .zip file.
I tried exporting the file with C# and SQL (BCB OR OLE) and all resulted into a corrupted file. So, I believe I am doing something wrong with in the making of the stream.
The C# code is the following:
private static byte[] GetStreamFileResult(Cookie loginCookie, Guid fileGuid, String baseUri)
{
byte[] output = null;
//String result = null;
string url = "some url"
CookieContainer cookies = new CookieContainer();
cookies.Add(new Uri(url), loginCookie);
WebRequest request = WebRequest.Create(url);
(request as HttpWebRequest).CookieContainer = cookies;
WebResponse response = request.GetResponse();
HttpWebResponse resp = response as HttpWebResponse;
Stream dataStream = response.GetResponseStream();
using (MemoryStream ms = new MemoryStream())
{
CopyStream(dataStream, ms);
output = ms.ToArray();
}
dataStream.Close();
response.Close();
return output;
}
The C# code to export the zip is the following:
File.WriteAllBytes("C:\\folder\\t.zip", stream); // Requires System.IO
The copy from stream to stream:
public static void CopyStream(Stream input, Stream output)
{
if (input != null)
{
using (StreamReader reader = new StreamReader(input))
using (StreamWriter writer = new StreamWriter(output))
{
writer.Write(reader.ReadToEnd());
}
}
}
Your CopyStream is broken. You need to talk binary. You're currently treating binary zip data as though it were text:
byte[] buffer = new byte[2048];
int bytesRead;
while((bytesRead = input.Read(buffer, 0, buffer.Length)) > 0) {
output.Write(buffer, 0, bytesRead);
}

C# FTP File from Object

I am trying to create an XML file from an object and save it to an FTP. My code successfully creates the file in the FTP, but the file just says NULL. PORequest is my object. Here is a screenshot:
Here is my code:
static void FTPXmlFile(PORequest req, string fileNameToCreate, string ftpUrl, string ftpPassword, string ftpUserName)
{
MemoryStream memoryStream = SerializeToStream(req);
// Get the object used to communicate with the server.
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(ftpUrl + fileNameToCreate);
request.Method = WebRequestMethods.Ftp.UploadFile;
// This example assumes the FTP site uses anonymous logon.
request.Credentials = new NetworkCredential(ftpUserName, ftpPassword);
request.UseBinary = false;
byte[] buffer = new byte[memoryStream.Length];
memoryStream.Read(buffer, 0, buffer.Length);
memoryStream.Close();
using (Stream reqStream = request.GetRequestStream())
{
reqStream.Write(buffer, 0, buffer.Length);
}
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
response.Close();
}
static MemoryStream SerializeToStream(object o)
{
MemoryStream stream = new MemoryStream();
IFormatter formatter = new BinaryFormatter();
formatter.Serialize(stream, o);
return stream;
}
Update:
Here is the code that worked:
static MemoryStream GetMemoryStream(object req)
{
XmlSerializer xmlSerializer = new XmlSerializer(req.GetType());
string s = null;
using (StringWriter textWriter = new StringWriter())
{
xmlSerializer.Serialize(textWriter, req);
s = textWriter.ToString();
}
MemoryStream memoryStream = new MemoryStream();
StreamWriter writer = new StreamWriter(memoryStream);
writer.Write(s);
writer.Flush();
memoryStream.Position = 0;
return memoryStream;
}

Downloading a torrent file with WebClient, results in corrupt file

I'm trying to download a .torrent file (not the contents of the torrent itself) in my .NET application.
Using the following code works for other files, but not .torrent. The resulting files is about 1-3kb smaller than if I download the file via a browser. When opening it in a torrent client, it says the torrent is corrupt.
WebClient web = new WebClient();
web.Headers.Add("Content-Type", "application/x-bittorrent");
web.DownloadFile("http://kat.ph/torrents/linux-mint-12-gnome-mate-dvd-64-bit-t6008958/", "test.torrent");
Opening the URL in a browser results in the file being downloaded correctly.
Any ideas as to why this would happen? Are there any good alternatives to WebClient that would download the file correctly?
EDIT: I've tried this as well as WebClient, and it results in the same thing:
private void DownloadFile(string url, string file)
{
byte[] result;
byte[] buffer = new byte[4096];
WebRequest wr = WebRequest.Create(url);
wr.ContentType = "application/x-bittorrent";
using (WebResponse response = wr.GetResponse())
{
using (Stream responseStream = response.GetResponseStream())
{
using (MemoryStream memoryStream = new MemoryStream())
{
int count = 0;
do
{
count = responseStream.Read(buffer, 0, buffer.Length);
memoryStream.Write(buffer, 0, count);
} while (count != 0);
result = memoryStream.ToArray();
using (BinaryWriter writer = new BinaryWriter(new FileStream(file, FileMode.Create)))
{
writer.Write(result);
}
}
}
}
}
The problem that server returns content compressed by gzip and you download this compressed content to file. For such cases you should check the "Content-Encoding" header and use proper stream reader to decompress the source.
I modified your function to handle gzipped content:
private void DownloadFile(string url, string file)
{
byte[] result;
byte[] buffer = new byte[4096];
WebRequest wr = WebRequest.Create(url);
wr.ContentType = "application/x-bittorrent";
using (WebResponse response = wr.GetResponse())
{
bool gzip = response.Headers["Content-Encoding"] == "gzip";
var responseStream = gzip
? new GZipStream(response.GetResponseStream(), CompressionMode.Decompress)
: response.GetResponseStream();
using (MemoryStream memoryStream = new MemoryStream())
{
int count = 0;
do
{
count = responseStream.Read(buffer, 0, buffer.Length);
memoryStream.Write(buffer, 0, count);
} while (count != 0);
result = memoryStream.ToArray();
using (BinaryWriter writer = new BinaryWriter(new FileStream(file, FileMode.Create)))
{
writer.Write(result);
}
}
}
}

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