UPDATED
See post #3 below.
There is a need to upload a file to the web automatically (without browser). Host - Mini File Host v1.2 (if this does matter). Didn't find specific api in documentation, so at first i sniffed browser requests in Firebug as follows :
Params : do
Value : verify
POST /upload.php?do=verify HTTP/1.1
Host: webfile.ukrwest.net
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; ru; rv:1.9.0.8) Gecko/2009032609 Firefox/3.0.8 (.NET CLR 4.0.20506)
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: ru,en-us;q=0.7,en;q=0.3
Accept-Encoding: gzip,deflate
Accept-Charset: windows-1251,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://filehoster.awardspace.com/index.php
Content-Type: multipart/form-data; boundary=---------------------------27368237179714
Content-Length: 445
-----------------------------27368237179714
Content-Disposition: form-data; name="upfile"; filename="Test.file"
Content-Type: application/octet-stream
12345678901011121314151617sample text
-----------------------------27368237179714
Content-Disposition: form-data; name="descr"
-----------------------------27368237179714
Content-Disposition: form-data; name="pprotect"
-----------------------------27368237179714--
Here we can see parameter, headers, content type and chunks of information (1 - file name and type, 2 - file contents, 3 - additional params - description and password, not necessarily applied). So i've created a class that emulates such a behaviour step by step : HttpWebRequest on the url, apply needed parameters to request, form request strings with StringBuilder and convert them to byte arrays, read a file using FileStream, putting all that stuff to MemoryStream and then writing it to request (took major part of a code from an article at CodeProject where it uploads a file to Rapidshare host). Neat and tidy, but... It doesn't seem to work :(. As result it returns initial upload page, not a result page with links i could parse and present to a user... Here are main methods of an Uploader class :
// Step 1 - request creation
private HttpWebRequest GetWebrequest(string boundary)
{
Uri uri = new Uri("http://filehoster.awardspace.com/index.php?do=verify");
System.Net.HttpWebRequest httpWebRequest = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(uri);
httpWebRequest.CookieContainer = _cookies;
httpWebRequest.ContentType = "multipart/form-data; boundary=" + boundary;
httpWebRequest.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.2; ru; rv:1.9.0.8) Gecko/2009032609 Firefox/3.0.8 (.NET CLR 4.0.20506)";
httpWebRequest.Referer = "http://filehoster.awardspace.com/index.php";
httpWebRequest.Method = "POST";
httpWebRequest.KeepAlive = true;
httpWebRequest.Timeout = -1;
//httpWebRequest.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
httpWebRequest.Headers.Add("Accept-Charset", "windows-1251,utf-8;q=0.7,*;q=0.7");
httpWebRequest.Headers.Add("Accept-Encoding", "gzip,deflate");
httpWebRequest.Headers.Add("Accept-Language", "ru,en-us;q=0.7,en;q=0.3");
//httpWebRequest.AllowAutoRedirect = true;
//httpWebRequest.ProtocolVersion = new Version(1,1);
//httpWebRequest.SendChunked = true;
//httpWebRequest.Headers.Add("Cache-Control", "no-cache");
//httpWebRequest.ServicePoint.Expect100Continue = false;
return httpWebRequest;
}
// Step 2 - first message part (before file contents)
private string GetRequestMessage(string boundary, string FName, string description, string password)
{
System.Text.StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append("--");
stringBuilder.Append(boundary);
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Disposition: form-data; name=\"");
stringBuilder.Append("upfile");
stringBuilder.Append("\"; filename=\"");
stringBuilder.Append(FName);
stringBuilder.Append("\"");
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Type: application/octet-stream");
stringBuilder.Append("\r\n");
return stringBuilder.ToString();
}
// Step 4 - additional request parameters. Step 3 - reading file is in method below
private string GetRequestMessageEnd(string boundary)
{
System.Text.StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append(boundary);
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Disposition: form-data; name=\"descr\"");
stringBuilder.Append("\r\n");
stringBuilder.Append("\r\n");
stringBuilder.Append("Default description");
stringBuilder.Append("\r\n");
stringBuilder.Append(boundary);
stringBuilder.Append("\r\n");
stringBuilder.Append("Content-Disposition: form-data; name=\"pprotect\"");
stringBuilder.Append("\r\n");
stringBuilder.Append("\r\n");
stringBuilder.Append("");
stringBuilder.Append("\r\n");
stringBuilder.Append(boundary);
stringBuilder.Append("--");
//stringBuilder.Append("\r\n");
//stringBuilder.Append(boundary);
//stringBuilder.Append("\r\n");
return stringBuilder.ToString();
}
// Main method
public string ProcessUpload(string FilePath, string description, string password)
{
// Chosen file information
FileSystemInfo _file = new FileInfo(FilePath);
// Random boundary generation
DateTime dateTime2 = DateTime.Now;
long l2 = dateTime2.Ticks;
string _generatedBoundary = "----------" + l2.ToString("x");
// Web request creation
System.Net.HttpWebRequest httpWebRequest = GetWebrequest(_generatedBoundary);
// Main app block - form and send request
using (System.IO.FileStream fileStream = new FileStream(_file.FullName, FileMode.Open, FileAccess.Read, FileShare.Read))
{
byte[] bArr1 = Encoding.ASCII.GetBytes("\r\n--" + _generatedBoundary + "\r\n");
// Generating pre-content post message
string firstPostMessagePart = GetRequestMessage(_generatedBoundary, _file.Name, description, password);
// Writing first part of request
byte[] bArr2 = Encoding.UTF8.GetBytes(firstPostMessagePart);
Stream memStream = new MemoryStream();
memStream.Write(bArr1, 0, bArr1.Length);
memStream.Write(bArr2, 0, bArr2.Length);
// Writing file
byte[] buffer = new byte[1024];
int bytesRead = 0;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
{
memStream.Write(buffer, 0, bytesRead);
}
// Generating end of a post message
string secondPostMessagePart = GetRequestMessageEnd(_generatedBoundary);
byte[] bArr3 = Encoding.UTF8.GetBytes(secondPostMessagePart);
memStream.Write(bArr3, 0, bArr3.Length);
// Preparing to send
httpWebRequest.ContentLength = memStream.Length;
fileStream.Close();
Stream requestStream = httpWebRequest.GetRequestStream();
memStream.Position = 0;
byte[] tempBuffer = new byte[memStream.Length];
memStream.Read(tempBuffer, 0, tempBuffer.Length);
memStream.Close();
// Sending request
requestStream.Write(tempBuffer, 0, tempBuffer.Length);
requestStream.Close();
}
// Delay (?)
System.Threading.Thread.Sleep(5000);
// Getting response
string strResponse = "";
using (Stream stream = httpWebRequest.GetResponse().GetResponseStream())
using (StreamReader streamReader = new StreamReader(stream/*, Encoding.GetEncoding(1251)*/))
{
strResponse = streamReader.ReadToEnd();
}
return strResponse;
}
Plays with ProtocolVersion (1.0, 1.1), AllowAutoRedirect (true/false), even known ServicePoint.Expect100Continue (false) didn't fix an issue. Even a 5sec timeout before getting response (thought in case of a big file it doesn't uploads so quick) didn't help. Content type "octet-stream" was chosen by purpose to upload any file (could use some switch for most popular jpg/zip/rar/doc etc., but that one seems universal). Boundary is generated randomly from timer ticks, not a big deal. What else? :/ I could give up and forget this, but i feel i'm pretty close to solve and then forget about it :P. In case you need the whole application to run and debug - here it is (70kb, zipped C# 2.0 VS2k8 solution, no ads, no viruses) :
Update : nope, there is no redirect.
Read RFC2388 few times, rewrote the code and it finally worked (i guess the trouble was in utf-read trailing boundary instead of correct 7 bit ascii). Hooray? Nope :(. Only small files are transfered, big ones throwing "The connection was closed unexpectedly".
System.Net.WebException was unhandled by user code
Message="The underlying connection was closed: The connection was closed unexpectedly."
Source="Uploader"
StackTrace:
at Uploader.Upload.ProcessUpload(String FilePath, String description, String password) in F:\MyDocuments\Visual Studio 2008\Projects\Uploader\Uploader.cs:line 96
at Uploader.Form1.backgroundWorker1_DoWork(Object sender, DoWorkEventArgs e) in F:\MyDocuments\Visual Studio 2008\Projects\Uploader\Form1.cs:line 45
at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)
I know that's a bug with .net stack and few solutions exists :
1) increase both Timeout and ReadWriteTimeout of request
2) assign request.KeepAlive = false and System.Net.ServicePointManager.Expect100Continue = false
3) set ProtocolVersion to 1.0 But neither one of them nor all of them altogether help in my case. Any ideas?
EDIT - Source code:
// .. request created, required params applied
httpWebRequest.ProtocolVersion = HttpVersion.Version10; // fix 1
httpWebRequest.KeepAlive = false; // fix 2
httpWebRequest.Timeout = 1000000000; // fix 3
httpWebRequest.ReadWriteTimeout = 1000000000; // fix 4
// .. request processed, data written to request stream
string strResponse = "";
try
{
using (WebResponse httpResponse = httpWebRequest.GetResponse()) // error here
{
using (Stream responseStream = httpResponse.GetResponseStream())
{
using (StreamReader streamReader = new StreamReader(responseStream))
{
strResponse = streamReader.ReadToEnd();
}
}
}
}
catch (WebException exception)
{
throw exception;
}
"As result it returns initial upload page, not a result page with links i could parse and present to a user..."
Maybe that's just the behaviour of the upload functionality: that after the upload has finished, you can upload another file? I think you have to call another url for the "browse for file"-page (I suppose that's the one you need).
Edit: Actually, if the server sends a "redirect" (http 3xx), that's something the browser has to handle, so if you're working with your own client application in stead of a browser, you'll have to implement redirection yourself. Here the rfc for more information.
Try setting the maxRequestLength property of the httpRuntime element in the Web.config.
In my case, duplicate filename causing the issue as well. I save the file's settings in an xml file but the name setting is duplicating each other.
<field name="StillImage">
<prefix>isp_main_</prefix>
<suffix>308</suffix>
<width>1080</width>
<height>1080</height>
</field>
<field name="ThumbnailImage">
<prefix>isp_thumb_</prefix> // pay attention to this
<suffix>308</suffix>
<width>506</width>
<height>506</height>
</field>
<field name="Logo">
<prefix>isp_thumb_</prefix> // and this
<suffix>306</suffix>
<width>506</width>
<height>506</height>
</field>
And, in the other case I had, the issue is in the file length. Please do check the allowed file size on your server. In your script just do check this part :
dataStream.Write(filesBytesArray, 0, filesBytesArray.Length);
dataStream.Close();
And if you dont know, just limit the file uploaded size in your frontend section ie. HTML <input type="file"> upload element, this is good reference for limiting file size and other filter.
来源：https://stackoverflow.com/questions/1060966/big-files-uploading-webexception-the-connection-was-closed-unexpectedly