Develop Reference

c# to get oauth2 token but get error (Remote server returns 400 Bad Request)

I am trying to use this C# to get oauth token from a website. But the below codes return '404 Bad Request' error. Is there anything wrong in my code? The website engineer says there should be a JSON file returned to show error details. How do I get that JSON file? What I can see is just 1 line error message in VS2012.
private void Button_Click_1(object sender, RoutedEventArgs e)
{
HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create("https://xxxx.com/api/oauth/token");
webRequest.Method = "POST";
webRequest.AllowAutoRedirect = true;
//write the data to post request
String postData = "client_id=abc&client_secret=xxx&grant_type=client_credentials";
byte[] buffer = Encoding.Default.GetBytes(postData);
if (buffer != null)
{
webRequest.ContentLength = buffer.Length;
webRequest.GetRequestStream().Write(buffer, 0, buffer.Length);
}
HttpWebResponse response = (HttpWebResponse)webRequest.GetResponse();
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
string strResponse = reader.ReadToEnd();
I used Postman to send a request and I can get the token in its response. How should I modify my C# codes to get the token?

Can you try like this
public (string, string, string, string) GetOAuth(string CliendId, string ClientSecret, string OAuthURl)
{
using (var httpClient = new HttpClient())
{
var creds = $"client_id={CliendId}&client_secret={ClientSecret}&grant_type=client_credentials";
httpClient.DefaultRequestHeaders.Accept.Clear();
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/x-www-form-urlencoded"));
var content = new StringContent(creds, Encoding.UTF8, "application/x-www-form-urlencoded");
var response = httpClient.PostAsync(OAuthURl, content).Result;
var jsonContent = response.Content.ReadAsStringAsync().Result;
var tokenObj = JsonConvert.DeserializeObject<dynamic>(jsonContent);
var access_token = tokenObj?.access_token;
var token_type = tokenObj?.token_type;
var expires_in = tokenObj?.expires_in;
var scope = tokenObj?.scope;
return (access_token, token_type, expires_in, scope);
}
}
private void HowTOUse()
{
string access_token, token_type, expires_in, scope;
(access_token, token_type, expires_in, scope) = GetOAuth("client_id", "client_secret", "oauthurl");
}

Try using like the below code hope this code will solve the problem
private void Button_Click_1(object sender, RoutedEventArgs e)
{
HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create("https://xxxx.com/api/oauth/token");
webRequest.Method = "POST";
webRequest.AllowAutoRedirect = true;
//write the data to post request
String postData =
"client_id=abc&client_secret=xxx&grant_type=client_credentials";
//byte[] buffer = Encoding.Default.GetBytes(postData);
//add these lines
byte[] buffer = System.Text.Encoding.ASCII.GetBytes(postData);
if (buffer != null)
{
webRequest.ContentLength = buffer.Length;
webRequest.GetRequestStream().Write(buffer, 0, buffer.Length);
}
try
{
using (HttpWebResponse response =
(HttpWebResponse)webRequest.GetResponse())
{
using (Stream dataStream = response.GetResponseStream())
{
StreamReader reader = new StreamReader(dataStream);
string strResponse = reader.ReadToEnd();
TokenModel dt = JsonConvert.DeserializeObject<TokenModel>
(strResponse);
token = dt.accessToken;
//Assign json Token values from strResponse to model tok_val
tok_val.accessToken = dt.accessToken;
tok_val.expires_in = dt.expires_in;
tok_val.RefreshToken = dt.RefreshToken;
tok_val.tokenType = dt.tokenType;
}
}
}
catch (WebException wex)
{
error = "Request Issue: " + wex.Message;
}
catch (Exception ex)
{
error = "Issue: " + ex.Message;
}

HttpWebResponse hangs/freezes when running in a WebAPI

I am using a C# WebAPI project which would call an external API based on its URL. However, when I am trying to retrieve the data back, it hangs/freezes.
The code where it stops is:
var response = (HttpWebResponse)await Task.Factory.FromAsync<WebResponse>(request.BeginGetResponse, request.EndGetResponse, null);
I don't understand why it is stopping though. Could it be interfering with the API request I am also making? When I run this code as part of a unit test, I would get a response back within seconds. I don't think it is the API service itself, I think it is my code. I have already tried various API URLS. None of them work.
My full code is:
public static async Task<string> CallWebAPi<T>(string url)
{
string returnValue;
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
request.ContentType = "application/json";
request.Method = "GET";
var response = (HttpWebResponse)await Task.Factory.FromAsync<WebResponse>(request.BeginGetResponse, request.EndGetResponse, null);
Stream stream = response.GetResponseStream();
StreamReader strReader = new StreamReader(stream);
returnValue = await strReader.ReadToEndAsync();
return returnValue;
}
Any help would be appreciated.

Possible deadlock ConfigureAwait(false), here are a good explanation from Stephen on what cause deadlocks.
var response = (HttpWebResponse)await Task.Factory.FromAsync<WebResponse>(request.BeginGetResponse, request.EndGetResponse, null).ConfigureAwait(false);

As a workaround you can use the synchronous functions, create a Task and await this task:
var response = await Task.Run(() =>
{
return (HttpWebResponse)request.GetResponse();
});

This is how i do my Request. Each Part is in an own Function. Its create the Request and you can get the Response synchronous.
public HttpWebRequest CreateRequest(string Url, string Method, string ContentType, object Content, List<RequestHeader> headers)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
request.Method = Method;
if (!string.IsNullOrWhiteSpace(ContentType)) request.ContentType = ContentType;
else if(Content != null) request.ContentType = "application/json";
if (Content != null)
{
var postData = Newtonsoft.Json.JsonConvert.SerializeObject(Content);
var data = Encoding.ASCII.GetBytes(postData);
request.ContentLength = data.Length;
using (var stream = request.GetRequestStream())
{
stream.Write(data, 0, data.Length);
}
}
foreach(RequestHeader header in Headers)
{
request.Headers.Add(header.Type, header.Value);
} //class at the end.
return request;
}
public string GetResponse(HttpWebRequest request)
{
var retval = "";
try
{
var response = (HttpWebResponse)request.GetResponse();
retval = ReadResponse(response);
response.Close();
}
catch (Exception ex)
{
resolveException(ex.Message);
}
return retval;
}
public string ReadResponse(HttpWebResponse response)
{
var retval = "";
try
{
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
var responseText = reader.ReadToEnd();
retval = responseText;
}
}
catch (Exception ex)
{
resolveException(ex.Message);
}
return retval;
}
public class RequestHeader
{
public HttpRequestHeader Type { get; set; }
public string Value { get; set; }
}

you dont need Task.Factory.FromAsync. HttpWebRequest already supports asynchronous operations.
You have defined a generic method CalWebApi<T> but have never used a generic type
if your operation is async, use this.
public async Task<T> CalWebApiAsync<T>(string url)
{
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
request.ContentType = "application/json";
request.Method = "GET";
using (var response = await request.GetResponseAsync())
{
using (var responseStream = response.GetResponseStream())
{
using (var streamReader = new StreamReader(responseStream))
{
var stringResult = await streamReader.ReadToEndAsync();
T objectResult = Newtonsoft.Json.JsonConvert.DeserializeObject<T>(stringResult);
return objectResult;
}
}
}
}
var result = await CallWebApiAsync<YourType>("exteranlapiurl");
if your operation is not async, use this..
public T CalWebApi<T>(string url)
{
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
request.ContentType = "application/json";
request.Method = "GET";
using (var response = request.GetResponse())
{
using (var responseStream = response.GetResponseStream())
{
using (var streamReader = new StreamReader(responseStream))
{
var stringResult = streamReader.ReadToEnd();
T objectResult = Newtonsoft.Json.JsonConvert.DeserializeObject<T>(stringResult);
return objectResult;
}
}
}
}
var result = CallWebApi<YourType>("exteranlapiurl");

How to call this Delete web api method in C#?

I have the following Delete WebAPI implemented, which is working fine and tested through swagger:
//Delete IVR Paycode Profiles
[System.Web.Http.HttpDelete, System.Web.Http.Route("PayCodeProfile")]
public System.Threading.Tasks.Task<ConfirmResponse> DeleteIVRPaycodeProfile(string profileIds)
{
string orgoid = HttpContext.Current.Request.Headers["ORGOID"];
SetContext(orgoid);
return _implementation.DeleteIVRPaycodeProfileAsync(orgoid, profileIds);
}
And I am calling from client like below:
var endpointURL = new Uri("http://localhost/ADP.TLM.IVR/TLM/v1/IVR/PayCodeProfile/1,2,3");
var request = WebRequest.Create(endpointURL) as HttpWebRequest;
if (request != null)
{
request.Headers.Add("ORGOID", "G344G4GEJXDJJ9M5");
// sending comma separated string of ids like 1,2,
// not sure if the ContentType is correct
request.ContentType = "text/html";
request.Method = "DELETE";
using (var response = request.GetResponse() as HttpWebResponse)
{
if (response != null)
{
var reader = new StreamReader(response.GetResponseStream());
var result = reader.ReadToEnd();
var resp = JsonConvert.DeserializeObject<ConfirmResponse>(result);
}
}
}
But I am getting 404:Not Found error, I believe that somewhere I am making a mistake for ContentType.

the problem is your url. at first you need to send the request to this address: "http://localhost/ADP.TLM.IVR/TLM/v1/IVR/PayCodeProfile". then depend on your content type(by default it is json) create your request. if your content type is json try this:
private static T Call<T>(string url, string body, int timeOut = 60)
{
var contentBytes = Encoding.UTF8.GetBytes(body);
var request = (HttpWebRequest)WebRequest.Create(url);
request.Timeout = timeOut * 1000;
request.ContentLength = contentBytes.Length;
request.Method = "DELETE";
request.ContentType = #"application/json";
using (var requestWritter = request.GetRequestStream())
requestWritter.Write(contentBytes, 0, (int)request.ContentLength);
var responseString = string.Empty;
var webResponse = (HttpWebResponse)request.GetResponse();
var responseStream = webResponse.GetResponseStream();
using (var reader = new StreamReader(responseStream))
{
reader.BaseStream.ReadTimeout = timeOut * 1000;
responseString = reader.ReadToEnd();
}
return JsonConvert.DeserializeObject<T>(responseString);
}
then call it like this:
var url = "http://localhost/ADP.TLM.IVR/TLM/v1/IVR/PayCodeProfile";
var body = JsonConvert.SerializeObject(new { profileIds = "1,2,3" });
var output = Call<dynamic>(url, body);

Get Access Token Using C#, Windows phone 8.1

I am trying to get the access token for the feed.Below is a code, i used to get the access token.
public async Task<string> GetAccessToken()
{
string postString = String.Format("username={0}&password={1}&grant_type=password", "userName", "pwd");
string url = "http://example.net/Token";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url.ToString());
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
UTF8Encoding utfenc = new UTF8Encoding();
byte[] bytes = utfenc.GetBytes(postString);
try
{
HttpWebResponse webResponse = (HttpWebResponse)(await request.GetResponseAsync());
Stream responseStream = webResponse.GetResponseStream();
StreamReader responseStreamReader = new StreamReader(responseStream);
string result = responseStreamReader.ReadToEnd();//parse token from result
}
catch(Exception ex)
{
}
return "";
}
The error below
"An error occurred while sending the request. The text associated with this error code could not be found.
The server name or address could not be resolved"
is throwing while it executes the below code
HttpWebResponse webResponse = (HttpWebResponse)(await request.GetResponseAsync());
Please help me to solve the issue

Try this if you are using POST request
public async Task<string> GetAccessToken()
{
string postString = String.Format("username={0}&password={1}&grant_type=password", "userName", "pwd");
try
{
using (var httpClient = new HttpClient())
{
var request1 = new HttpRequestMessage(HttpMethod.Post, "FeedURL");
request1.Content = new StringContent(postString);
var response = await httpClient.SendAsync(request1);
var result1 = await response.Content.ReadAsStringAsync();
result1 = Regex.Replace(result1, "<[^>]+>", string.Empty);
var rootObject1 = JObject.Parse(result1);
string accessToken = rootObject1["access_token"].ToString();
}
}
catch (Exception ex)
{
}
}

WP8 - Login to Website and parse HTML from answer

I want to login to this site: http://subcard.subway.co.uk/de_cardholder/JSP/login_reg.jsp
And i found out that I have to send a POST request to the server and I also know that I have to work with this POST request:
POST /de_cardholder/servlet/SPLoginServlet HTTP/1.1
Host: subcard.subway.co.uk
language=de&userID=ID&password=PASSWORD&transIdentType=1&programID=6
And after the login I want to parse the HTML data. But how can I implement the POST request on WP in C# and is it as easy as I think?

Try this,
Uri RequestUri = new Uri("subcard.subway.co.uk/de_cardholder/servlet/SPLoginServlet HTTP/1.1?language=de&userID=ID&password=PASSWORD&transIdentType=1&programID=6", UriKind.Absolute);
string PostData = "";
WebRequest webRequest;
webRequest = WebRequest.Create(RequestUri);
webRequest.Method = "POST";
webRequest.ContentType = "text/xml";
HttpWebResponse response;
string Response;
using (response = (HttpWebResponse)await webRequest.GetResponseAsync()) ;
using (Stream streamResponse = response.GetResponseStream())
using (StreamReader streamReader = new StreamReader(streamResponse))
{
Response = await streamReader.ReadToEndAsync();
}
if(Response != null)
{
//data should be available in Response
}

var postRequest = (HttpWebRequest)WebRequest.Create("your Url here");
postRequest.ContentType = "application/x-www-form-urlencoded";// you can give the type of request content here
postRequest.Method = "POST";
if you have any data to be posted along with the request as part of content and not as part of URL itself you can add this. example:- ( language=de&userID=ID&password=PASSWORD&transIdentType=1&programID=6)
using (var requestStream = await postRequest.GetRequestStreamAsync())
{
byte[] postDataArray = Encoding.UTF8.GetBytes("your request data");
await requestStream.WriteAsync(postDataArray, 0, postDataArray.Length);
}
if you do not have any data to be a send as content ignore the above code
WebResponse postResponse = await postRequest.GetResponseAsync();
if (postResponse != null)
{
var postResponseStream = postResponse.GetResponseStream();
var postStreamReader = new StreamReader(postResponseStream);
string response = await postStreamReader.ReadToEndAsync();// Result comes here
}