Develop Reference

Upload to S3 from HTTPWebResponse.GetResponseStream() in c#

I am trying to upload from an HTTP stream directly to S3, without storing in memory or as a file first. I am already doing this with Rackspace Cloud Files as HTTP to HTTP, however the AWS authentication is beyond me so am trying to use the SDK.
The problem is the upload stream is failing with this exception:
"This stream does not support seek operations."
I've tried with PutObject and TransferUtility.Upload, both fail with the same thing.
Is there any way to stream into S3 as the stream comes in, rather than buffering the whole thing to a MemoryStream or FileStream?
or is there any good examples of doing the authentication into S3 request using HTTPWebRequest, so I can duplicate what I do with Cloud Files?
Edit: or is there a helper function in the AWSSDK for generating the authorization header?
CODE:
This is the failing S3 part (both methods included for completeness):
string uri = RSConnection.StorageUrl + "/" + container + "/" + file.SelectSingleNode("name").InnerText;
var req = (HttpWebRequest)WebRequest.Create(uri);
req.Headers.Add("X-Auth-Token", RSConnection.AuthToken);
req.Method = "GET";
using (var resp = req.GetResponse() as HttpWebResponse)
{
using (Stream stream = resp.GetResponseStream())
{
Amazon.S3.Transfer.TransferUtility trans = new Amazon.S3.Transfer.TransferUtility(S3Client);
trans.Upload(stream, config.Element("root").Element("S3BackupBucket").Value, container + file.SelectSingleNode("name").InnerText);
//Use EITHER the above OR the below
PutObjectRequest putReq = new PutObjectRequest();
putReq.WithBucketName(config.Element("root").Element("S3BackupBucket").Value);
putReq.WithKey(container + file.SelectSingleNode("name").InnerText);
putReq.WithInputStream(Amazon.S3.Util.AmazonS3Util.MakeStreamSeekable(stream));
putReq.WithMetaData("content-length", file.SelectSingleNode("bytes").InnerText);
using (S3Response putResp = S3Client.PutObject(putReq))
{
}
}
}
And this is how I do it successfully from S3 to Cloud Files:
using (GetObjectResponse getResponse = S3Client.GetObject(new GetObjectRequest().WithBucketName(bucket.BucketName).WithKey(file.Key)))
{
using (Stream s = getResponse.ResponseStream)
{
//We can stream right from s3 to CF, no need to store in memory or filesystem.
var req = (HttpWebRequest)WebRequest.Create(uri);
req.Headers.Add("X-Auth-Token", RSConnection.AuthToken);
req.Method = "PUT";
req.AllowWriteStreamBuffering = false;
if (req.ContentLength == -1L)
req.SendChunked = true;
using (Stream stream = req.GetRequestStream())
{
byte[] data = new byte[32768];
int bytesRead = 0;
while ((bytesRead = s.Read(data, 0, data.Length)) > 0)
{
stream.Write(data, 0, bytesRead);
}
stream.Flush();
stream.Close();
}
req.GetResponse().Close();
}
}

As no-one answering seems to have done it, I spent the time working it out based on guidance from Steve's answer:
In answer to this question "is there any good examples of doing the authentication into S3 request using HTTPWebRequest, so I can duplicate what I do with Cloud Files?", here is how to generate the auth header manually:
string today = String.Format("{0:ddd,' 'dd' 'MMM' 'yyyy' 'HH':'mm':'ss' 'zz00}", DateTime.Now);
string stringToSign = "PUT\n" +
"\n" +
file.SelectSingleNode("content_type").InnerText + "\n" +
"\n" +
"x-amz-date:" + today + "\n" +
"/" + strBucketName + "/" + strKey;
Encoding ae = new UTF8Encoding();
HMACSHA1 signature = new HMACSHA1(ae.GetBytes(AWSSecret));
string encodedCanonical = Convert.ToBase64String(signature.ComputeHash(ae.GetBytes(stringToSign)));
string authHeader = "AWS " + AWSKey + ":" + encodedCanonical;
string uriS3 = "https://" + strBucketName + ".s3.amazonaws.com/" + strKey;
var reqS3 = (HttpWebRequest)WebRequest.Create(uriS3);
reqS3.Headers.Add("Authorization", authHeader);
reqS3.Headers.Add("x-amz-date", today);
reqS3.ContentType = file.SelectSingleNode("content_type").InnerText;
reqS3.ContentLength = Convert.ToInt32(file.SelectSingleNode("bytes").InnerText);
reqS3.Method = "PUT";
Note the added x-amz-date header as HTTPWebRequest sends the date in a different format to what AWS is expecting.
From there it was just a case of repeating what I was already doing.

Take a look at Amazon S3 Authentication Tool for Curl. From that web page:
Curl is a popular command-line tool for interacting with HTTP
services. This Perl script calculates the proper signature, then calls
Curl with the appropriate arguments.
You could probably adapt it or its output for your use.

I think the problem is that according to the AWS Documentation Content-Length is required and you don't know what the length is until the stream has finished.
(I would guess the Amazon.S3.Util.AmazonS3Util.MakeStreamSeekable routine is reading the whole stream into memory to get around this problem which makes it unsuitable for your scenario.)
What you can do is read the file in chunks and upload them using MultiPart upload.
PS, I assume you know the C# source for the AWSSDK for dotnet is on Github.

This is a true hack (which would probably break with a new implementation of the AWSSDK), and it requires knowledge of the length of the file being requested, but if you wrap the response stream as shown with this class (a gist) as shown below:
long length = fileLength;
you can get file length in several ways. I am uploading from a dropbox link, so they give me the
length along with the url. Alternatively, you can perform a HEAD request and get the Content-Length.
string uri = RSConnection.StorageUrl + "/" + container + "/" + file.SelectSingleNode("name").InnerText;
var req = (HttpWebRequest)WebRequest.Create(uri);
req.Headers.Add("X-Auth-Token", RSConnection.AuthToken);
req.Method = "GET";
using (var resp = req.GetResponse() as HttpWebResponse)
{
using (Stream stream = resp.GetResponseStream())
{
//I haven't tested this path
Amazon.S3.Transfer.TransferUtility trans = new Amazon.S3.Transfer.TransferUtility(S3Client);
trans.Upload(new HttpResponseStream(stream, length), config.Element("root").Element("S3BackupBucket").Value, container + file.SelectSingleNode("name").InnerText);
//Use EITHER the above OR the below
//I have tested this with dropbox data
PutObjectRequest putReq = new PutObjectRequest();
putReq.WithBucketName(config.Element("root").Element("S3BackupBucket").Value);
putReq.WithKey(container + file.SelectSingleNode("name").InnerText);
putReq.WithInputStream(new HttpResponseStream(stream, length)));
//These are necessary for really large files to work
putReq.WithTimeout(System.Threading.Timeout.Infinite);
putReq.WithReadWriteTimeout(System.Thread.Timeout.Infinite);
using (S3Response putResp = S3Client.PutObject(putReq))
{
}
}
}
The hack is overriding the Position and Length properties, and returning 0 for Position{get}, noop'ing Position{set}, and returning the known length for Length.
I recognize that this might not work if you don't have the length or if the server providing the source does not support HEAD requests and Content-Length headers. I also realize it might not work if the reported Content-Length or the supplied length doesn't match the actual length of the file.
In my test, I also supply the Content-Type to the PutObjectRequest, but I don't that that is necessary.

As sgmoore said, the problem is that your content length is not seekable from the HTTP response. However HttpWebResponse does have a content length property available. So you can actually form your Http post request to S3 yourself instead of using the Amazon library.
Here's another Stackoverflow question that managed to do that with what looks like full code to me.

HttpWebRequest POST Login error 405

Im trying to make a small login system but i have this problem that when the project runs on VS2010 it says :
The remote server returned an error: (405) Method Not Allowed.
Heres my code:
//Our URL
string uri = "https://************************/ValidateUsername";
//Our postvars
byte[] buffer = Encoding.ASCII.GetBytes( "username=user" );
//Initialization
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.Accept = "application/json;odata=verbose";
request.Headers.Add("Language", "es-MX");
request.Headers.Add("Application", "-------------------");
request.Headers.Add("Version", "1.0");
//Our method is POST, otherway buffer would be useless
request.Method = "POST";
//We use form contentType, for the postvars
request.ContentType = "application/x-www-form-urlencoded";
//The lenght of the content its set by postvars (buffer) lenght
request.ContentLength = buffer.Length;
//We open a stream for writing the postvars
Stream PostData = request.GetRequestStream();
//Now we write, and afterwards, we close.
PostData.Write(buffer, 0, buffer.Length);
When i hover the pointer over "PostData" and then i go to the length and position attributes, i can read :
Length = 'PostData.Length' threw an exception of type 'System.NotSupportedException'
base {System.SystemException} = {"This stream does not support seek operations."}
im not sure if this is the real problem, but im trying to give the mos of information possible.
PostData.Close();
//Get the response Handle
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
//lets show info about the response
Console.WriteLine("Estatus de la respuesta:" + response.StatusCode);
Console.WriteLine("Servidor : " + response.Server);
//Now we read the response (the string), and output it
//Stream answer = response.GetResponseStream();
//StreamReader _answer = new StreamReader(answer);
//Console.WriteLine("Respuesta: " + _answer.ReadToEnd());
At some forum i read that maybe the "_answer.ReadToEnd()" could be the problem but even thought i commented , the problem still arises.
Im doing this so i can try it later on windows phone, dont know if im wasting my time , because they are not related.
I hope someone can help. Thanks in advance.

Error while reading response from HttpWebRequest

I am trying to send contents of 1GB text file over the network. I modified the suggested code for basic authentication and kept it as follows :
WRequest = (HttpWebRequest)HttpWebRequest.Create(URL);
WRequest.Credentials = Credentials;
WRequest.PreAuthenticate = true;
WRequest.ContentType = "text/plain";
WRequest.Method = "POST";
WRequest.AllowWriteStreamBuffering = false;
WRequest.Timeout = 10000;
FileStream ReadIn = new FileStream(filename, FileMode.Open, FileAccess.Read);
ReadIn.Seek(0, SeekOrigin.Begin);
WRequest.ContentLength = ReadIn.Length;
Byte[] FileData = new Byte[ReadIn.Length];
int DataRead = 0;
Stream tempStream = WRequest.GetRequestStream();
do
{
DataRead = ReadIn.Read(FileData, 0, 2048);
if (DataRead > 0)
{
tempStream.Write(FileData, 0, DataRead);
Array.Clear(FileData, 0, 2048);
}
} while (DataRead > 0);
// The response
WResponse = (HttpWebResponse)WRequest.GetResponse();
However, now it gives me System.Net.ProtocolViolationException error : "You must write ContentLength bytes to the request stream before calling [Begin]GetResponse". I checked HttpWebRequest.BeginGetRequestResponse ... and found from debugging that the contentlength for WRequest is not -1. What else could be going wrong ? How should I get the response ?
Update :
The code which worked for small files is as followed :
WebRequest request = WebRequest.Create(url);
request.Method = "POST";
request.Credentials = Credentials;
using (StreamReader reader = new StreamReader(filename))
{
postData = reader.ReadToEnd();
}
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
request.ContentType = "text/plain";
request.ContentLength = byteArray.Length;
Stream dataStream = request.GetRequestStream();
dataStream.Write(byteArray, 0, byteArray.Length);
dataStream.Close();
// The response
WebResponse response = request.GetResponse();
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
dataStream = response.GetResponseStream();
using (StreamReader reader = new StreamReader(dataStream))
{
responseFromServer = reader.ReadToEnd();
}
dataStream.Close();
response.Close();

The article you referenced says
If the Microsoft Internet Information Services (IIS) Web server is configured to use Basic authentication, and you must set the HttpWebRequest.AllowWriteStreamBuffering property to false, you must send a HEAD request to pre-authenticate the connection before you send the POST or PUT request.
EDIT - now with more clarification!
To restate the article, if you want to send a large file to a destination which requires basic authentication, you'll need to issue two separate requests. The key here is that you are setting PreAuthenticate = true. Read the statement literally -- by setting the property to true, you are saying that you will authenticate any requests that you make before you actually attempt them! The framework doesn't know how you want to accomplish this pre-authentication, so you need to perform that action yourself, by sending a HEAD request to the destination. Think of the HEAD HTTP method as being a prologue to the actual request - it describes (or requests information about) a particular resource.
So the process goes like this:
Make a HEAD request to http://someurl/aresource containing the credentials you want to use when making future requests from this client to that server for the listed resource
The server will respond (ideally) with "OK - you may proceed. You're authenticated"
The server immediately regrets its' decision to allow the operation as it finds itself saving a very large file :-)
I don't see you making that HEAD request anywhere in the code you posted - if it's not already there, add this at the beginning of your code (snipped from the sample article ref in OP):
//preAuth the request
// You can add logic so that you only pre-authenticate the very first request.
// You should not have to pre-authenticate each request.
WRequest = (HttpWebRequest)HttpWebRequest.Create(URL);
// Set the username and the password.
WRequest.Credentials = new NetworkCredential(user, password);
WRequest.PreAuthenticate = true;
WRequest.UserAgent = "Upload Test";
WRequest.Method = "HEAD";
WRequest.Timeout = 10000;
WResponse = (HttpWebResponse)WRequest.GetResponse();
WResponse.Close();
// Make the real request.

Need help with HttpWebRequest on a Compact Framework Project

not so long ago I´ve created a small iphone app for my Daily use. Now I want to port this app to a Windows Mobile Device while using C# and the Compact Framework. But I really have no clue how to use the HttpWebRequest and the msdn doesn´t help me either. I think I have a lag of understanding on how Web Requests work in general.
In the iPhone app I have the following lines code:
NSMutableURLRequest *theRequest = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:#"https://xxx:xxx#api.test.net/RPC2"]];
[theRequest setHTTPMethod:#"POST"];
[theRequest addValue:#"text/xml" forHTTPHeaderField:#"content-type"];
[theRequest setCachePolicy:NSURLCacheStorageNotAllowed];
[theRequest setTimeoutInterval:5.0];
NSString* pStr = [[NSString alloc] initWithFormat:#"<?xml version=\"1.0\" encoding=\"UTF-8\"?><methodCall><methodName>xxx.SessionInitiate</methodName><params><param><value><struct><member><name>LocalUri</name><value><string></string></value></member><member><name>RemoteUri</name><value><string>xxxx</string></value></member><member><name>TOS</name><value><string>text</string></value></member><member><name>Content</name><value><string>%#</string></value></member><member><name>Schedule</name><value><string></string></value></member></struct></value></param></params></methodCall>", number.text, TextView.text];
NSData* pBody = [pStr dataUsingEncoding:NSUTF8StringEncoding];
[theRequest setHTTPBody:pBody];
NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
The Webservice has no wsdl so I have to use the HttpWebRquest Object in .Net CF.
What I didn´t get is, where to put the Body (the long XML) in my Request?
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(#"https://xxx:xxx#api.xxx.net/RPC2");
req.Method = #"POST";
req.ContentType = #"test/xml";
req.Timeout = 5;
I started this way, is the first line it´s own HttpWebRequest and for the XML Body I have to create anotherone?! How do I use it correctly, how do I send it? Sorry if this might be normaly totaly easy but I really don´t get it. I´ve searched the web, 2 Books and the msdn but in every tutorial is only a Webrequest with an URL but without a body.
Thank you
twickl

You need to write the POST data to the request stream.
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(#"https://username:password#api.sipgate.net/RPC2");
req.Method = "POST";
req.ContentType = "test/xml";
req.Timeout = 5;
using (Stream stream = req.GetRequestStream())
using (StreamWriter writer = new StreamWriter(stream, Encoding.UTF8))
{
writer.Write("PUT THE XML HERE");
}
using (StreamReader reader = req.GetResponse().GetResponseStream())
{
string result = reader.ReadToEnd();
}

Get the request stream using
Stream requestStream = req.GetRequestStream();
Then write your xml data to the stream, taking care to encode your text.
Don't forget to close the stream to ensure that all of your data is sent.
requestStream.Close();

BEWARE, if there's no data to write to the stream, the ContentLength would be 0 but oddly you STILL need to Dispose() the RequestStream even if you don't write anything to it!!!
req.ContentLength = 0;
req.GetRequestStream().Dispose();
This problem only happens in Compact Framework.
I want my 8 hours back, and my hair too...

Problems consuming WebService in .Net (ReCaptcha)

I am having difficulty in consuming the reCaptcha Web Service using C#/.Net 3.5. Although I think the problem is with consuming web services in general.
String validate = String.Format("http://api-verify.recaptcha.net/verify?privatekey={0}&remoteip={1}&challenge={2}&response={3}", PrivateKey, UserIP, Challenge, Response);
WebClient serviceRequest = new WebClient();
serviceRequest.Headers.Add("ContentType","application/x-www-form-urlencoded")
String response = serviceRequest.DownloadString(new Uri(validate ));
It keeps telling me that the error is: nverify-params-incorrect. Which means:
The parameters to /verify were incorrect, make sure you are passing all the required parameters.
But it's correct. I am using the private key, the IP address (locally) is 127.0.0.1, and the challenge and response seem fine. However the error keeps occurring.
I am pretty sure this is a issue with how I am requesting the service as this is the first time I have actually used webservices and .Net.
I also tried this as it ensures the data is posted:
String queryString = String.Format("privatekey={0}&remoteip={1}&challenge={2}&response={3}",PrivateKey, UserIP, Challenge, Response);
String Validate = "http://api-verify.recaptcha.net/verify" + queryString;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(new Uri(Validate));
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = Validate.Length;
**HttpWebResponse captchaResponse = (HttpWebResponse)request.GetResponse();**
String response;
using (StreamReader reader = new StreamReader(captchaResponse.GetResponseStream()))
response = reader.ReadToEnd();
Seems to stall at the point where I get response.
Any advice?
Thanks in advance

Haven't worked with the recaptcha service previously, but I have two troubleshooting recommendations:
Use Fiddler or Firebug and watch what you're sending outbound. Verifying your parameters would help you with basic troubleshooting, i.e. invalid characters, etc.
The Recaptcha Wiki has an entry about dealing with development on Vista. It doesn't have to be limited to Vista, though; if you're system can handle IPv6, then your browser could be communicating in that format as a default. It appears as if Recaptcha deals with IPv4. Having Fiddler/Firebug working would tell you about those other parameters that could be causing you grief.
This may not help solve your problem but it might provide you with better troubleshooting info.

So got this working, for some reason I needed to write the request to a stream like so:
//Write data to request stream
using (Stream requestSteam = request.GetRequestStream())
requestSteam.Write(byteData, 0, byteData.Length);
Could anyone explain why this works. I didn't think I would need to do this, don't completely understand what's happening behind the scenes..

Damien's answer is correct of course, but just to be clear about the order of things (I was a little confused) and to have a complete code sample...
var uri = new Uri("http://api-verify.recaptcha.net/verify");
var queryString = string.Format(
"privatekey={0}&remoteip={1}&challenge={2}&response={3}",
privateKey,
userIP,
challenge,
response);
var request = (HttpWebRequest)HttpWebRequest.Create(uri);
request.Method = WebRequestMethods.Http.Post;
request.ContentLength = queryString.Length;
request.ContentType = "application/x-www-form-urlencoded";
using (var writer = new StreamWriter(request.GetRequestStream()))
{
writer.Write(queryString);
}
string result;
using (var webResponse = (HttpWebResponse)request.GetResponse())
{
var reader = new StreamReader(webResponse.GetResponseStream());
result = reader.ReadToEnd();
}
There's a slight difference in that I'm writing the post variables to the request, but the core of it is the same.