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Bitstamp API POST request with parameters

please, help me with POST api request in C#.I dont know how to correctly send parameters „key“, „signature“ and „nonce“ in POST request. It constantly tells me "Missing key, signature and nonce parameters“.
HttpWebRequest webRequest =(HttpWebRequest)System.Net.WebRequest.Create("https://www.bitstamp.net/api/balance/");
if (webRequest != null)
{
webRequest.Method = HttpMethod.Post;
webRequest.ContentType = "application/json";
webRequest.UserAgent = "BitstampBot";
byte[] data = Convert.FromBase64String(apisecret);
string nonce = GetNonce().ToString();
var prehash = nonce + custID + apikey;
string signature = HashString(prehash, data);
body = Serialize(new
{
key=apikey,
signature=signature,
nonce=nonce
});
if (!string.IsNullOrEmpty(body))
{
var data1 = Encoding.UTF8.GetBytes(body);
webRequest.ContentLength = data1.Length;
using (var stream = webRequest.GetRequestStream()) stream.Write(data1, 0, data1.Length);
}
using (Stream s = webRequest.GetResponse().GetResponseStream())
{
using (StreamReader sr = new System.IO.StreamReader(s))
{
contentBody = await sr.ReadToEndAsync();
return contentBody;
}
}
}

The "Request parameters" as Bitstamp specifies in the docs is actually supposed to be sent with content type "application/x-www-form-urlencoded" instead of "application/json".
I would also use HttpClient to perform the post as that has a much more simple setup to perform Http requests
using (var client = new HttpClient())
{
var content = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("key", apikey),
new KeyValuePair<string, string>("signature", signature),
new KeyValuePair<string, string>("nonce", nonce)
});
var result = await client.PostAsync("https://www.bitstamp.net/api/balance/", content);
string resultContent = await result.Content.ReadAsStringAsync();
}

How to send object as POST parameters to ASP.Net web request?

I'm trying to make web requests programmatically in ASP.NET, using the POST method.
I'd like to send POST parameters with the web request as well. Something like this:
LoginData obj = new LoginData();
obj.OSVersion = deviceInformation.OperatingSystem;
obj.DeviceModel = deviceInformation.FriendlyName;
string URI = "https://XXXXXXXXX.azure-mobile.net/user/logsuserin";
HttpWebRequest GETRequest = (HttpWebRequest)HttpWebRequest.Create(new Uri(URI, UriKind.RelativeOrAbsolute));
GETRequest.Method = "POST";
GETRequest.ContentType = "application/x-www-form-urlencoded";
GETRequest.Headers["applicationKey"] = "UFakeKkrayuAeVnoVAcjY54545455544";
//GETRequest.Parameters.add(obj);
Obviously, the commented line does not work. How do I achieve this?
How to get a response by sending my obj as params?
Thanks in advance,
Hemanth.

You need to use theGetRequestStream() method belonging to the HttpWebRequest
void Main()
{
LoginData obj = new LoginData
{
Username = "foo",
Password = "Bar"
};
byte[] objBytes = Encoding.UTF8.GetBytes(obj.ToString());
// obj.OSVersion = deviceInformation.OperatingSystem;
// obj.DeviceModel = deviceInformation.FriendlyName;
string URI = "https://XXXXXXXXX.azure-mobile.net/user/logsuserin";
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(new Uri(URI, UriKind.RelativeOrAbsolute));
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.Headers["applicationKey"] = "UFakeKkrayuAeVnoVAcjY54545455544";
request.ContentLength = objBytes.Length;
using (Stream stream = request.GetRequestStream())
{
stream.Write(objBytes, 0, objBytes.Length);
}
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
using (Stream stream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(stream))
{
Console.WriteLine(reader.ReadToEnd());
}
}
public class LoginData
{
public string Username { get; set; }
public string Password { get; set; }
public string OSVersion { get; set; }
public string DeviceModel { get; set; }
public override string ToString()
{
var temp = this.GetType()
.GetProperties()
.Select(p => $"{p.Name}={HttpUtility.UrlEncode(p.GetValue(this).ToString())}");
return string.Join("&", temp);
}
}

If you want to use HttpClient:
using (var client = new HttpClient())
{
var request = new HttpRequestMessage(HttpMethod.Post, "https://XXXXXXXXX.azure-mobile.net/user/logsuserin");
request.Headers.Add("applikationKey", "UFakeKkrayuAeVnoVAcjY54545455544");
request.Content = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("OSVersion", deviceInformation.OperatingSystem),
new KeyValuePair<string, string>("DeviceModel", deviceInformation.FriendlyName),
});
var response = client.SendAsync(request).GetAwaiter().GetResult();
}

You can dynamically generate a FORM with "NameValueCollection". Using "NameValueCollection" you can add number of objects to be posted as -
NameValueCollection FormFields = new NameValueCollection();
FormFields.Add("abc", obj1);
FormFields.Add("xyz", obj2);
Response.Clear();
Response.Write("<html><head>");
Response.Write(string.Format("</head><body onload=\"document.{0}.submit()\">", FormName));
Response.Write(string.Format("<form name=\"{0}\" method=\"{1}\" action=\"{2}\" >", FormName, Method, Url));
for (int i = 0; i < FormFields.Keys.Count; i++)
{
Response.Write(string.Format("<input name=\"{0}\" type=\"hidden\" value=\"{1}\">", FormFields.Keys[i], FormFields[FormFields.Keys[i]]));
}
Response.Write("</form>");
Response.Write("</body></html>");
Response.End();
OnLoad() of this form you can POST to desired URL.

call HttpPost method from Client in C# code

I am new to MVC and C#, so sorry if this question seems too basic.
For a HttpPost Controller like below, how do to call this method directly from a client-side program written in C#, without a browser (NOT from a UI form in a browser with a submit button)? I am using .NET 4 and MVC 4.
I am sure the answer is somehwere on the web, but haven't found one so far. Any help is appreciated!
[HttpPost]
public Boolean PostDataToDB(int n, string s)
{
//validate and write to database
return false;
}

For example with this code in the server side:
[HttpPost]
public Boolean PostDataToDB(int n, string s)
{
//validate and write to database
return false;
}
You can use different approches:
With WebClient:
using (var wb = new WebClient())
{
var data = new NameValueCollection();
data["n"] = "42";
data["s"] = "string value";
var response = wb.UploadValues("http://www.example.org/receiver.aspx", "POST", data);
}
With HttpRequest:
var request = (HttpWebRequest)WebRequest.Create("http://www.example.org/receiver.aspx");
var postData = "n=42&s=string value";
var data = Encoding.ASCII.GetBytes(postData);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = data.Length;
using (var stream = request.GetRequestStream())
{
stream.Write(data, 0, data.Length);
}
var response = (HttpWebResponse)request.GetResponse();
var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
With HttpClient:
using (var client = new HttpClient())
{
var values = new List<KeyValuePair<string, string>>();
values.Add(new KeyValuePair<string, string>("n", "42"));
values.Add(new KeyValuePair<string, string>("s", "string value"));
var content = new FormUrlEncodedContent(values);
var response = await client.PostAsync("http://www.example.org/receiver.aspx", content);
var responseString = await response.Content.ReadAsStringAsync();
}
With WebRequest
WebRequest request = WebRequest.Create ("http://www.example.org/receiver.aspx");
request.Method = "POST";
string postData = "n=42&s=string value";
byte[] byteArray = Encoding.UTF8.GetBytes (postData);
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = byteArray.Length;
Stream dataStream = request.GetRequestStream ();
dataStream.Write (byteArray, 0, byteArray.Length);
dataStream.Close ();
//Response
WebResponse response = request.GetResponse ();
Console.WriteLine (((HttpWebResponse)response).StatusDescription);
dataStream = response.GetResponseStream ();
StreamReader reader = new StreamReader (dataStream);
string responseFromServer = reader.ReadToEnd ();
Console.WriteLine (responseFromServer);
reader.Close ();
dataStream.Close ();
response.Close ();
see msdn

You can use
First of all you should return valid resutl:
[HttpPost]
public ActionResult PostDataToDB(int n, string s)
{
//validate and write to database
return Json(false);
}
After it you can use HttpClient class from Web Api client libraries NuGet package:
public async bool CallMethod()
{
var rootUrl = "http:...";
bool result;
using (var client = new HttpClient())
{
client.BaseAddress = new Uri(_rootUrl);
var response= await client.PostAsJsonAsync(methodUrl, new {n = 10, s = "some string"});
result = await response.Content.ReadAsAsync<bool>();
}
return result;
}
You can also use WebClient class:
[HttpPost]
public Boolean PostDataToDB(int n, string s)
{
//validate and write to database
return false;
}
public async bool CallMethod()
{
var rootUrl = "http:...";
bool result;
using (var client = new WebClient())
{
var col = new NameValueCollection();
col.Add("n", "1");
col.Add("s", "2");
var res = await client.UploadValuesAsync(address, col);
string res = Encoding.UTF8.GetString(res);
result = bool.Parse(res);
}
return result;
}

If you decide to use HttpClient implementation. Do not create and dispose of HttpClient for each call to the API. Instead, re-use a single instance of HttpClient. You can achieve that declaring the instance static or implementing a singleton pattern.
Reference: https://aspnetmonsters.com/2016/08/2016-08-27-httpclientwrong/
How to implement singleton (good starting point, read the comments on that post): https://codereview.stackexchange.com/questions/149805/implementation-of-a-singleton-httpclient-with-generic-methods

Hopefully below code will help you
[ActionName("Check")]
public async System.Threading.Tasks.Task<bool> CheckPost(HttpRequestMessage request)
{
string body = await request.Content.ReadAsStringAsync();
return true;
}

Turning HttpWebResponse into an HttpResponseMessage

I have the following action in an asp.net WebAPI controller:
public HttpResponseMessage GetCBERSS(string Site, string File, string User, string Password)
{
string URLString = string.Format("https://{0}.rss.mycompany.com/{1}", Site, File);
Uri uri = new Uri(URLString);
CredentialCache cache = new CredentialCache();
cache.Add(uri, "Basic", new NetworkCredential(User, Password));
WebRequest r = WebRequest.Create(uri);
r.Credentials = cache;
r.ContentType = "application/rss+xml";
IgnoreBadCertificates();
HttpWebResponse result = (HttpWebResponse)r.GetResponse();
return ???;
}
How can I convert the HttpWebResponse into an HttpResponseMessage?

The best way to transform HttpWebResponse in HttpResponseMessage is create a new HttpResponseMessage :
using (var responseApi = (HttpWebResponse)request.GetResponse())
{
var response = new HttpResponseMessage(responseApi.StatusCode);
using (var reader = new StreamReader(responseApi.GetResponseStream()))
{
var objText = reader.ReadToEnd();
response.Content = new StringContent(objText, Encoding.UTF8, "application/json");
}
return response;
}

calling google Url Shortner API in C#

I want to call the google url shortner API from my C# Console Application, the request I try to implement is:
POST https://www.googleapis.com/urlshortener/v1/url
Content-Type: application/json
{"longUrl": "http://www.google.com/"}
When I try to use this code:
using System.Net;
using System.Net.Http;
using System.IO;
and the main method is:
static void Main(string[] args)
{
string s = "http://www.google.com/";
var client = new HttpClient();
// Create the HttpContent for the form to be posted.
var requestContent = new FormUrlEncodedContent(new[] {new KeyValuePair<string, string>("longUrl", s),});
// Get the response.
HttpResponseMessage response = client.Post("https://www.googleapis.com/urlshortener/v1/url",requestContent);
// Get the response content.
HttpContent responseContent = response.Content;
// Get the stream of the content.
using (var reader = new StreamReader(responseContent.ContentReadStream))
{
// Write the output.
s = reader.ReadToEnd();
Console.WriteLine(s);
}
Console.Read();
}
I get the error code 400: This API does not support parsing form-encoded input.
I don't know how to fix this.

you can check the code below (made use of System.Net).
You should notice that the contenttype must be specfied, and must be "application/json"; and also the string to be send must be in json format.
using System;
using System.Net;
using System.IO;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://www.googleapis.com/urlshortener/v1/url");
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "POST";
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
{
string json = "{\"longUrl\":\"http://www.google.com/\"}";
Console.WriteLine(json);
streamWriter.Write(json);
}
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var responseText = streamReader.ReadToEnd();
Console.WriteLine(responseText);
}
}
}
}

Google has a NuGet package for using the Urlshortener API. Details can be found here.
Based on this example you would implement it as such:
using System;
using System.Net;
using System.Net.Http;
using Google.Apis.Services;
using Google.Apis.Urlshortener.v1;
using Google.Apis.Urlshortener.v1.Data;
using Google.Apis.Http;
namespace ConsoleTestBed
{
class Program
{
private const string ApiKey = "YourAPIKey";
static void Main(string[] args)
{
var initializer = new BaseClientService.Initializer
{
ApiKey = ApiKey,
//HttpClientFactory = new ProxySupportedHttpClientFactory()
};
var service = new UrlshortenerService(initializer);
var longUrl = "http://wwww.google.com/";
var response = service.Url.Insert(new Url { LongUrl = longUrl }).Execute();
Console.WriteLine($"Short URL: {response.Id}");
Console.ReadKey();
}
}
}
If you are behind a firewall you may need to use a proxy. Below is an implementation of the ProxySupportedHttpClientFactory, which is commented out in the sample above. Credit for this goes to this blog post.
class ProxySupportedHttpClientFactory : HttpClientFactory
{
private static readonly Uri ProxyAddress
= new UriBuilder("http", "YourProxyIP", 80).Uri;
private static readonly NetworkCredential ProxyCredentials
= new NetworkCredential("user", "password", "domain");
protected override HttpMessageHandler CreateHandler(CreateHttpClientArgs args)
{
return new WebRequestHandler
{
UseProxy = true,
UseCookies = false,
Proxy = new WebProxy(ProxyAddress, false, null, ProxyCredentials)
};
}
}

How about changing
var requestContent = new FormUrlEncodedContent(new[]
{new KeyValuePair<string, string>("longUrl", s),});
to
var requestContent = new StringContent("{\"longUrl\": \" + s + \"}");

Following is my working code. May be its helpful for you.
private const string key = "xxxxxInsertGoogleAPIKeyHerexxxxxxxxxx";
public string urlShorter(string url)
{
string finalURL = "";
string post = "{\"longUrl\": \"" + url + "\"}";
string shortUrl = url;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://www.googleapis.com/urlshortener/v1/url?key=" + key);
try
{
request.ServicePoint.Expect100Continue = false;
request.Method = "POST";
request.ContentLength = post.Length;
request.ContentType = "application/json";
request.Headers.Add("Cache-Control", "no-cache");
using (Stream requestStream = request.GetRequestStream())
{
byte[] postBuffer = Encoding.ASCII.GetBytes(post);
requestStream.Write(postBuffer, 0, postBuffer.Length);
}
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
using (Stream responseStream = response.GetResponseStream())
{
using (StreamReader responseReader = new StreamReader(responseStream))
{
string json = responseReader.ReadToEnd();
finalURL = Regex.Match(json, #"""id"": ?""(?.+)""").Groups["id"].Value;
}
}
}
}
catch (Exception ex)
{
// if Google's URL Shortener is down...
System.Diagnostics.Debug.WriteLine(ex.Message);
System.Diagnostics.Debug.WriteLine(ex.StackTrace);
}
return finalURL;
}