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Webclient equivalent of CURL command

I am trying to upload a file via a POST to a REST API in a c# winform.
If I run the following command with curl the file is uploaded successfully:
curl.exe -H "Content-type: application/octet-stream" -X POST http://myapiurl --data-binary #C:\test.docx
I have tried using WebClient in my WinForm:
using (var client = new WebClient())
{
client.Headers.Add("Content-Type", "application/octet-stream");
byte[] result = client.UploadFile(url, file);
string responseAsString = Encoding.Default.GetString(result);
tb_result.Text += responseAsString;
}
But I just get a (500) Internal Server.
Checking this with fiddler the following headers are added with CURL:
POST http://myapiurl HTTP/1.1
User-Agent: curl/7.33.0
Host: 10.52.130.121:90
Accept: */*
Connection: Keep-Alive
Content-type: application/octet-stream
Content-Length: 13343
Expect: 100-continue
But checking my WebClient method shows the following:
POST http://myapiurl HTTP/1.1
Accept: */*
Content-Type: multipart/form-data; boundary=---------------------8d220bbd95f8b18
Host: 10.52.130.121:90
Content-Length: 13536
Expect: 100-continue
Connection: Keep-Alive
How can I simulate the CURL command above from my app?

How can I simulate the CURL command above from my app?
Use HttpWebRequest. It offers you more flexibility. As follows:
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://myapiurl");
request.Method = "POST";
request.UserAgent = "curl/7.33.0";
request.Host = "10.52.130.121:90";
request.Accept = "Accept=*/*";
request.Connection = "Keep-Alive";
request.ContentType = "application/octet-stream";
request.ContentLength = 13343;
request.Expect = "100-continue";

HttpWebRequest and Cookie handling

Sending cookie received from httpwebrequest is not giving correct result however if i copy paste cookie value from browser cookie than it returns correct result. why i am not getting result from httpwebrequest but works perfectly fine from browser?
CookieContainer cookieContainer = new CookieContainer();
var targetUri = new Uri("URL1");
HttpWebRequest myHttpWebRequest = (HttpWebRequest)HttpWebRequest.Create(targetUri);
myHttpWebRequest.Method = "GET";
myHttpWebRequest.CookieContainer = cookieContainer;
//Get Response
HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();
//Create Request
targetUri = new Uri("URL2");
myHttpWebRequest = (HttpWebRequest)HttpWebRequest.Create(targetUri);
myHttpWebRequest.Method = "GET";
myHttpWebRequest.CookieContainer = cookieContainer;
//Get Response
myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();
using (StreamReader reader = new StreamReader(myHttpWebResponse.GetResponseStream()))
{
string html = reader.ReadToEnd();
}
Following is second request(URL2) fiddler with cookie received through first request(URL1):
Request:
GET URL2
HTTP/1.1
Host: www.xyz.com
Cookie: JSESSIONID=Mn7qJwrRnxLn1NNfT1PNr1L2Gr2KCkfFVCRS1wfsT4zfzWJhT62J!-876337174
Response:
HTTP/1.1 200 OK
Date: Fri, 27 Feb 2015 13:03:52 GMT
Content-Length: 13
Content-Type: text/html;charset=UTF-8
X-Powered-By: Servlet/2.5 JSP/2.1
Now if i copy paste first url(URL1) in browser and use cookie value from browser then it returns correct result:
Request:
GET URL2
HTTP/1.1
Host: www.xyz.com
Cookie: JSESSIONID=PPPHJwmKQNh2ykVXytlcfTDH2YWNbtv76vPBzZTG3Dfdm9Mx0J74!-876337174
Response:
HTTP/1.1 200 OK
Date: Fri, 27 Feb 2015 13:06:15 GMT
Content-Type: text/html;charset=UTF-8
X-Powered-By: Servlet/2.5 JSP/2.1
Content-Length: 21417

Weblogic is returning the cookies in the response, and you need to send it back in the next request.
cookieContainer.Add(response.Cookies);
(Your cookieContainer is on your machine and is empty).

C# WebClient HTTP Basic Authentication Failing 401 with Correct Credentials

I'm trying to automate configuring a wireless router's SSID and Password via c# webclient. The router has no API that I know of. It's an unbranded chinese router. The web config seems to be the only option for configuration. It uses http-basic-authentication (you browse to the IP address of the router and get a generic dialog asking for username and password).
I've used Wireshark to get the headers and form fields that the http-post requests use when I manually update the SSID and Password (two separate forms). I then attempted to use webclient to emulate those post requests.
Here is a snippet of code that I am using to attempt to save a new SSID (NameValueCollection is defined elsewhere):
private const string FORM_SSID = "http://192.168.1.2/formWlanSetup.htm";
private const string REF_SSID = "http://192.168.1.2/formRedirect.htm?redirect-url=wlbasic.htm&wlan_id=0";
private NameValueCollection mFields = HttpUtility.ParseQueryString(string.Empty, Encoding.ASCII);
public string SaveConfigResponse()
{
try
{
using (WebClient wc = new WebClient())
{
wc.Headers[HttpRequestHeader.Accept] = "text/html, application/xhtml+xml, */*";
wc.Headers[HttpRequestHeader.Referer] = REF_SSID;
wc.Headers[HttpRequestHeader.AcceptLanguage] = "en-US";
wc.Headers[HttpRequestHeader.UserAgent] = "Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko";
wc.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
wc.Headers[HttpRequestHeader.AcceptEncoding] = "gzip, deflate";
wc.Headers[HttpRequestHeader.Host] = "192.168.1.2";
wc.Headers[HttpRequestHeader.Connection] = "Keep-Alive";
wc.Headers[HttpRequestHeader.ContentLength] = Encoding.ASCII.GetBytes(mFields.ToString()).Length.ToString();
wc.Headers[HttpRequestHeader.CacheControl] = "no-cache";
string credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(config_user + ":" + config_pass));
wc.Headers[HttpRequestHeader.Authorization] = string.Format("Basic {0}", credentials);
//wc.Credentials = new NetworkCredential("admin", "admin");
return Encoding.ASCII.GetString(wc.UploadValues(FORM_SSID, "POST", mFields));
}
}
catch (Exception ex)
{
return ex.Message;
}
}
This results in an http-status-code-401 not authorized response. Is what I'm trying to do just impossible?
UPDATE
Here are the HTTP headers of both the browser post/response and the WebClient post/response. Again, I tried to match what I saw the browser posting as well as I could with my WebClient post.
Browser:
POST /formWlanSetup.htm HTTP/1.1
Accept: text/html, application/xhtml+xml, */*
Referer: http://192.168.1.2/formRedirect.htm?redirect-url=wlbasic.htm&wlan_id=0
Accept-Language: en-US
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko
Content-Type: application/x-www-form-urlencoded
Accept-Encoding: gzip, deflate
Host: 192.168.1.2
Content-Length: 524
Connection: Keep-Alive
Cache-Control: no-cache
Authorization: Basic YWRtaW46YWRtaW4=
HTTP/1.1 302 Found
Location: wlbasic.htm
Content-Length: 183
Date: Thu, 23 Oct 2014 18:18:27 GMT
Server: eCos Embedded Web Server
Connection: close
Content-Type: text/html
Transfer-Encoding: chunked
Cache-Control: no-cache
WebClient:
POST /formWlanSetup.htm HTTP/1.1
Accept-Language: en-US
Accept-Encoding: gzip, deflate
Cache-Control: no-cache
Authorization: Basic YWRtaW46YWRtaW4=
Accept: text/html, application/xhtml+xml, */*
Content-Type: application/x-www-form-urlencoded
Referer: http://192.168.1.2/formRedirect.htm?redirect-url=wlbasic.htm&wlan_id=0
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko
Host: 192.168.1.2
Content-Length: 524
Connection: Keep-Alive
HTTP/1.1 401 Not Authorized
WWW-Authenticate: Basic realm="AP"
Date: Thu, 23 Oct 2014 18:18:41 GMT
Server: eCos Embedded Web Server
Connection: close
Content-Type: text/html
Transfer-Encoding: chunked
Cache-Control: no-cache
Again, that was all gleaned from Wireshark. I'm not very familiar with Wireshark, but I was able to get this far. If I knew how to properly extract the raw packet data and pastebin it, I would.
Important New Observations
The Wireshark captures of the post packets from both Browser and WebClient obviously differ in the order of the headers. I don't know how significant that might or might not be, though, as the data for each header is clearly the same.
One stark difference between the packets that I noticed is that Wireshark reports the Browser packet to be significantly larger than the WebClient packet. Looking at the itemized view, I couldn't find any obvious differences. I assume posting raw data for comparison would reveal a lot, but again, I don't really know how to do that.
I had a bewildering revelation. Despite the response clearly stating '(401) Unauthorized', the post is in fact being accepted by the router! Driving in to the router's web config after my WebClient post shows that the settings were accepted and saved.
That last one is a biggie. I find myself in a situation where I can get my config to save with a WebClient post, but I have to ignore a 401 response in order to do so. Obviously, this is far from ideal. So close, yet so far!
FINAL UPDATE (RESOLUTION)
I've solved the issue of failing basic authentication, though not with WebClient. I used the suggestion from #caesay and went with HttpWebRequest (together with WebResponse). My form posts result in redirects, so I had to allow for that.
This is essentially what I went with:
private bool ConfigureRouter()
{
bool passed = false;
string response = "";
HttpWebRequest WEBREQ = null;
WebResponse WEBRESP = null;
// Attempt to POST form to router that saves a new SSID.
try
{
var uri = new Uri(FORM_SSID); // Create URI from URL string.
WEBREQ = HttpWebRequest.Create(uri) as HttpWebRequest;
// If POST will result in redirects, you won't see an "OK"
// response if you don't allow those redirects
WEBREQ.AllowAutoRedirect = true;
// Basic authentication will first send the request without
// creds. This is protocol standard.
// When the server replies with 401, the HttpWebRequest will
// automatically send the request again with the creds when
// when PreAuthenticate is set.
WEBREQ.PreAuthenticate = true;
WEBREQ.AuthenticationLevel = System.Net.Security.AuthenticationLevel.MutualAuthRequested;
// Mimic all headers known to satisfy the request
// as discovered with a tool like Wireshark or Fiddler
// when the form was submitted from a browser.
WEBREQ.Method = "POST";
WEBREQ.Accept = "text/html, application/xhtml+xml, */*";
WEBREQ.Headers.Add("Accept-Language", "en-US"); // No AcceptLanguage property built-in to HttpWebRequest
WEBREQ.UserAgent = USER_AGENT;
WEBREQ.Referer = REF_SSID;
WEBREQ.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
WEBREQ.KeepAlive = true;
WEBREQ.Headers.Add("Pragma", "no-cache"); // No Pragma property built-in to HttpWebRequest
// Use a cached credential so that the creds are properly
// submitted with subsequent redirect requests.
CredentialCache creds = new CredentialCache();
creds.Add(uri, "Basic", new NetworkCredential(config_user, config_pass));
WEBREQ.Credentials = creds;
// Submit the form.
using (Stream stream = WEBREQ.GetRequestStream())
{
SSID ssid = new SSID(ssid_scanned); // Gets predefined form fields with new SSID inserted (NameValueCollection PostData)
stream.Write(ssid.PostData, 0, ssid.PostData.Length);
}
// Get the response from the final redirect.
WEBRESP = WEBREQ.GetResponse();
response = ((HttpWebResponse)WEBRESP).StatusCode.ToString();
if (response == "OK")
{
StatusUpdate("STATUS: SSID save was successful.");
passed = true;
}
else
{
StatusUpdate("FAILED: SSID save was unsuccessful.");
passed = false;
}
WEBRESP.Close();
}
catch (Exception ex)
{
StatusUpdate("ERROR: " + ex.Message);
return false;
}
return passed;
}

Is what I'm trying to do just impossible?
No, its not impossible. I have had many headaches with web scraping like this over the years because some web servers are picky, and your router interface is likely a custom web server implementation that isnt as forgiving as apache or iis.
I would do a wireshark capture and get the raw packet data that chrome sends (w/ payload etc), and then do the same capture for your application. Make sure the packets are as similar as you can get them. If you still have issues, post the packet captures to pastebin or something so we can have a look.
EDIT::
Instead of using the limited WebClient API, try using some lower level items, I wonder if the following code will work for you:
var uri = new Uri("http://192.168.1.2/formWlanSetup.htm");
var cookies = new CookieContainer();
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.CookieContainer = cookies;
request.ServicePoint.Expect100Continue = false;
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko";
request.Referer = "http://192.168.1.2/formRedirect.htm?redirect-url=wlbasic.htm&wlan_id=0";
request.Credentials = new NetworkCredential(config_user, config_pass);
request.PreAuthenticate = true;
var response = request.GetResponse();
var reader = new StreamReader(response.GetResponseStream());
string htmlResponse = reader.ReadToEnd();

Malformed string exception while sending "&" in Json to AppEngine

I am trying to send Facebook graph link to the AppEngine server. I receive "Malformed string exception". Here is my method sending json to server:
public async Task<string> SendJSONData(string urlToCall, string JSONData)
{
// server to POST to
string url = urlToCall;
// HTTP web request
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
httpWebRequest.ContentType = "application/x-www-form-urlencoded";
httpWebRequest.Method = "POST";
// Write the request Asynchronously
using (var stream = await Task.Factory.FromAsync<Stream>(httpWebRequest.BeginGetRequestStream,
httpWebRequest.EndGetRequestStream, null))
{
//create some json string
string json = "action=" + JSONData;
// convert json to byte array
byte[] jsonAsBytes = Encoding.UTF8.GetBytes(json);
// Write the bytes to the stream
await stream.WriteAsync(jsonAsBytes, 0, jsonAsBytes.Length);
}
WebResponse response = await httpWebRequest.GetResponseAsync();
StreamReader requestReader = new StreamReader(response.GetResponseStream());
String webResponse = requestReader.ReadToEnd();
return webResponse; }
Here is what I sniff using Fiddler:
POST http://x.appspot.com/register HTTP/1.1
Accept: */*
Content-Length: 376
Accept-Encoding: identity
Content-Type: application/x-www-form-urlencoded
User-Agent: NativeHost
Host: x.appspot.com
Connection: Keep-Alive
Pragma: no-cache
action={
"mailFb": "mail#gmail.com",
"userName": "Michael",
"userSurname": "w00t",
"nickname": "Michael w00t",
"userSex": "male",
"userAvatar": "https://graph.facebook.com/myperfectid/picture?type=large&access_token=BlahblahblahblahToken"
}
So everything looks fine, but the problem is that i receive the following error in AppEngine log:
2013-03-02 17:52:10.431 /register 500 56ms 0kb NativeHost
W 2013-03-02 17:52:10.427 /register com.google.gson.JsonSyntaxException: com.google.gson.stream.MalformedJsonException: Unterminated string at line 7 column 79 at com.google.g
C 2013-03-02 17:52:10.429 Uncaught exception from servlet com.google.gson.JsonSyntaxException: com.google.gson.stream.MalformedJsonException: Unterminated string at line 7 colu
I managed to narrow the problem to its source, which is "&" character. So my question is, how to fix the code, so that it works with AppEngine.
Oh, here is how i read the received data on the server:
gson.fromJson(reader, User.class);

The problem is highlighted by the fact you're claiming you are sending "Content-Type: application/x-www-form-urlencoded"
But it isn't. Hence the error.
The correct encoding for & is &.

HttpWebRequest and Set-Cookie header in response not parsed (WP7)

I am trying to get the header "Set-Cookie" or access the cookie container, but the Set-Cookie header is not available.
The cookie is in the response header, but it's not there in the client request object.
I am registering the ClientHttp stack using
bool httpResult = WebRequest.RegisterPrefix("http://", WebRequestCreator.ClientHttp);
Here's the response:
HTTP/1.1 200 OK
Content-Type: application/xml; charset=utf-8
Connection: keep-alive
Status: 200
X-Powered-By: Phusion Passenger (mod_rails/mod_rack) 3.0.0.pre4
ETag: "39030a9c5a45a24e485e4d2fb06c6389"
Client-Version: 312, 105, 0, 0
X-Runtime: 44
Content-Length: 1232
Set-Cookie: _CWFServer_session=[This is the session data]; path=/; HttpOnly
Cache-Control: private, max-age=0, must-revalidate
Server: nginx/0.7.67 + Phusion Passenger 3.0.0.pre4 (mod_rails/mod_rack)
<?xml version="1.0" encoding="UTF-8"?>
<user>
...
</user>
My callback code contains something like:
var webRequest = (HttpWebRequest)result.AsyncState;
raw = webRequest.EndGetResponse(result) as HttpWebResponse;
foreach (Cookie c in webRequest.CookieContainer.GetCookies(webRequest.RequestUri))
{
Console.WriteLine("Cookie['" + c.Name + "']: " + c.Value);
}
I've also tried looking at the headers but Set-Cookie header isn't present in the response either.
Any suggestions on what may be the problem?

Try explicitly passing a new CookieContainer:
CookieContainer container = new CookieContainer();
container.Add(new Uri("http://yoursite"), new Cookie("name", "value"));
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://yoursite");
request.CookieContainer = container;
request.BeginGetResponse(new AsyncCallback(GetData), request);

You are receiving HttpOnly cookies:
Set-Cookie: _CWFServer_session=[This is the session data]; path=/; HttpOnly
For security reasons, those cookies can't be accessed from code, but you still can use them in your next calls to HttpWebRequest. More on this here : Reading HttpOnly Cookies from Headers of HttpWebResponse in Windows Phone
With WP7.1, I also had problems reading non HttpOnly cookies. I found out that they are not available if the response of the HttpWebRequest comes from the cache. Making the query unique with a random number solved the cache problem :
// The Request
Random random = new Random();
// UniqueQuery is used to defeat the cache system that destroys the cookie.
_uniqueQuery = "http://my-site.somewhere?someparameters=XXX"
+ ";test="+ random.Next();
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(_uniqueQuery);
request.BeginGetResponse(Response_Completed, request);
Once you get the response, you can fetch the cookie from the response headers:
void Response_Completed(IAsyncResult result)
{
HttpWebRequest request = (HttpWebRequest)result.AsyncState;
HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(result);
String header = response.Headers["Set-Cookie"];
I never managed to get the CookieContainer.GetCookies() method to work.

Is the cookie httponly? If so, you won't be able to see it, but if you use the same CookieContainer for your second request, the request will contain the cookie, even though your program won't be able to see it.

You must edit the headers collection directly. Something like this:
request.Headers["Set-Cookie"] = "name=value";
request.BeginGetResponse(myCallback, request);