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HttpWebRequest.getResponse() returning NULL

I am attempting to create a console app that sends a WebRequest to a website so that I can get some information back from it in JSON format. Once I build up the request and try to get response I just want to simply print out the data, but when I call httpWebRequest.getResponse() it returns NULL.
I have tried multiple other methods of sending the data to the the url but those are all giving me like 404, or 400 errors, etc. This method at least isn't giving me any error, just a NULL.
Here is a snapshot of the documentation I am using for the API (albeit the docs aren't complete yet):
Here is the console app code that I have right now:
try
{
var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://api.remot3.it/apv/v27/user/login");
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "POST";
httpWebRequest.Headers.Add("developerkey", "***KEY***");
using (var streamWriter = new
StreamWriter(httpWebRequest.GetRequestStream()))
{
string json = new JavaScriptSerializer().Serialize(new
{
email = "***EMAIL***",
password = "***PASSWORD***"
});
Console.WriteLine(json);
streamWriter.Write(json);
}
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
Console.WriteLine(result);
Console.ReadLine();
}
}catch(Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine(e.StackTrace);
Console.ReadLine();
}
Expected output is some JSON data, but I am getting a NULL back from getResponse().

Try to serialize the credential in your form and for header send as parameter for this class.
Check below for my code. It is not 100 % fit to your requirement, but atleast it will help to get through your logic.
Here is what I get Json Response from this code. Its work Perfect. Please remember to add timeout option on your webrequest and at the end close the streamreader and stream after completing your task. please check this code.
public static string httpPost(string url, string json)
{
string content = "";
byte[] bs;
if (json != null && json != string.Empty)
{
bs = Encoding.UTF8.GetBytes(json);
}
else
{
bs = Encoding.UTF8.GetBytes(url);
}
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url);
req.Method = "POST";
if (json != string.Empty)
req.ContentType = "application/json";
else
req.ContentType = "application/x-www-form-urlencoded";
req.KeepAlive = false;
req.Timeout = 30000;
req.ReadWriteTimeout = 30000;
//req.UserAgent = "test.net";
req.Accept = "application/json";
req.ContentLength = bs.Length;
using (Stream reqStream = req.GetRequestStream())
{
reqStream.Write(bs, 0, bs.Length);
reqStream.Flush();
reqStream.Close();
}
using (WebResponse wr = req.GetResponse())
{
Stream s = wr.GetResponseStream();
StreamReader reader = new StreamReader(s, Encoding.UTF8);
content = reader.ReadToEnd();
wr.Close();
s.Close();
reader.Close();
}
return content;
}

using OpenTSDB HTTP api in .NET : 400 Bad Request

I'm trying to use .net to put datapoints in OpenTSDB, using the HTTP /api/put API.
I've tried with httpclient, webRequest and HttpWebRequest. The outcome is always 400 - bad request: chunked request not supported.
I've tried my payload with an api tester (DHC) and works well.
I've tried to send a very small payload (even plain wrong, like "x") but the reply is always the same.
Here's one of my code instances:
public async static Task PutAsync(DataPoint dataPoint)
{
try
{
HttpWebRequest http = (HttpWebRequest)WebRequest.Create("http://127.0.0.1:4242/api/put");
http.SendChunked = false;
http.Method = "POST";
http.ContentType = "application/json";
Encoding encoder = Encoding.UTF8;
byte[] data = encoder.GetBytes( dataPoint.ToJson() + Environment.NewLine);
http.Method = "POST";
http.ContentType = "application/json; charset=utf-8";
http.ContentLength = data.Length;
using (Stream stream = http.GetRequestStream())
{
stream.Write(data, 0, data.Length);
stream.Close();
}
WebResponse response = http.GetResponse();
var streamOutput = response.GetResponseStream();
StreamReader sr = new StreamReader(streamOutput);
string content = sr.ReadToEnd();
Console.WriteLine(content);
}
catch (WebException exc)
{
StreamReader reader = new StreamReader(exc.Response.GetResponseStream());
var content = reader.ReadToEnd();
}
return ;
}
where I explicitly set to false the SendChunked property.
note that other requests, like:
public static async Task<bool> Connect(Uri uri)
{
HttpWebRequest http = (HttpWebRequest)WebRequest.Create("http://127.0.0.1:4242/api/version");
http.SendChunked = false;
http.Method = "GET";
// http.Headers.Clear();
//http.Headers.Add("Content-Type", "application/json");
http.ContentType = "application/json";
WebResponse response = http.GetResponse();
var stream = response.GetResponseStream();
StreamReader sr = new StreamReader(stream);
string content = sr.ReadToEnd();
Console.WriteLine(content);
return true;
}
work flawlessly.
I am sure I am doing something really wrong.
I'd like to to reimplement HTTP in Sockets from scratch.

I've found a solution I'd like to share here.
I've used wireshark to sniff my packets, and I've found that this header is added:
Expect: 100-continue\r\n
(see 8.2.3 of https://www.w3.org/Protocols/rfc2616/rfc2616-sec8.html)
This is the culprit. I've read the post http://haacked.com/archive/2004/05/15/http-web-request-expect-100-continue.aspx/ by Phil Haack, and found that HttpWebRequest puts that header by default, unless you tell it to stop. In this article I've found that using ServicePointManager I can do just this.
Putting the following code on top of my method, when declaring the http object, makes it work very well, and solves my issue:
var uri = new Uri("http://127.0.0.1:4242/api/put");
var spm = ServicePointManager.FindServicePoint(uri);
spm.Expect100Continue = false;
HttpWebRequest http = (HttpWebRequest)WebRequest.Create(uri);
http.SendChunked = false;

WCF WebInvoke POST message body

[OperationContract]
[WebInvoke(UriTemplate = "s={s}", Method = "POST")]
string EchoWithPost(string s);
I'm trying to consume this method (WCF service) using a WebRequest:
WebRequest request1 = WebRequest.Create("http://MyIP/Host");
request1.Method = "POST";
request1.ContentType = "application/x-www-form-urlencoded";
string postData1 = "s=TestString";
I don't want to pass the data (s=TestString) in the url, what I'm trying to do is passing the data in the message body.

First you need to change your service contract like this:
[OperationContract]
[WebInvoke(UriTemplate = "EchoWithPost", Method = "POST")]
string EchoWithPost(string s);
Notice how the UriTemplate is no longer expecting any variable value in the URL.
To invoke such an operation from a client:
// Set up request
string postData = #"""Hello World!""";
HttpWebRequest request =
(HttpWebRequest)WebRequest.Create("http://MyIP/Host/EchoWithPost");
request.Method = "POST";
request.ContentType = "text/json";
byte[] dataBytes = new ASCIIEncoding().GetBytes(postData);
request.ContentLength = dataBytes.Length;
using (Stream requestStream = request.GetRequestStream())
{
requestStream.Write(dataBytes, 0, dataBytes.Length);
}
// Get and parse response
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
string responseString = string.Empty;
using (var responseStream = new StreamReader(response.GetResponseStream()))
{
//responseData currently will be in XML format
//<string xmlns="http://schemas.microsoft.com/2003/10/Serialization/">Hello World!</string>
var responseData = responseStream.ReadToEnd();
responseString = System.Xml.Linq.XDocument.Parse(responseData).Root.Value;
}
// display response - Hello World!
Console.WriteLine(responseString);
Console.ReadKey();

Request uri too long with webservice

I want to do a create via a webservice which needs a uri like this:
http://<url>/webservice.php?operation=<operation>&elementType=<elementType>&element=<element>&
my problem is, element is all information of an email with html body, which is about 6000 characters.
I want to call the url like this:
var request = WebRequest.Create(urlToUse.ToString());
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = urlToUse.Length;
var requestStream = request.GetRequestStream();
var requestStreamWriter = new StreamWriter(requestStream);
requestStreamWriter.Write(urlToUse);
requestStreamWriter.Close();
var response = request.GetResponse();
var responseStream = response.GetResponseStream();
if (responseStream == null) return null;
var responseStreamReader = new StreamReader(responseStream);
var responseFromServer = responseStreamReader.ReadToEnd();
responseStreamReader.Close();
responseStream.Close();
response.Close();
but it breaks at
var response = request.GetResponse();
and says the uri is too long.
I can't change the server's max length of the url and the webservice needs the parameters in the url.
I haven't found a suitable solution for me yet so any help is appreciated.Update:
For anyone facing the same issue, the solution that worked for me was to put my query into an byte-Array like
var encoding = new UTF8Encoding();
byte[] bytes = enconding.GetBytes((queryString));
and writing that into the webrequest instead of my queryString
var stream = request.GetRequestStream();
stream.Write(bytes, 0, bytes.Length);

You can put data in the body of the request with something a little like this:
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("http://<url>/webservice.php");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var jsonContent = JsonConvert.SerializeObject(new YourObject
{
// Pseudo code... Replace <...> with your values etc
Operation = <YourOperation>,
ElementType = <YourElementType>,
Element = <YourElement>,
// etc...
});
HttpResponseMessage response;
using (HttpContent httpContent = new StringContent(jsonContent, Encoding.UTF8, "application/json"))
{
response = await client.PostAsync("youroperation/", httpContent);
}
// Do something with response if you want
}
This is JSON based but could be anything you want to pass... This is a simple example that will hopefully give you an idea of how you can proceed.

You need to split the urlToUse at the question mark:
Something like this (not tested)
string[] parts = urlToUse.ToString().Split(new char[]{'?'}, 2);
string url = parts[0];
string data = parts[1];
var request = WebRequest.Create(url);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = data.Length;
var requestStream = request.GetRequestStream();
var requestStreamWriter = new StreamWriter(requestStream);
requestStreamWriter.Write(data);
requestStreamWriter.Close();
var response = request.GetResponse();
var responseStream = response.GetResponseStream();
if (responseStream == null) return null;
var responseStreamReader = new StreamReader(responseStream);
var responseFromServer = responseStreamReader.ReadToEnd();
responseStreamReader.Close();
responseStream.Close();
response.Close();
Good luck with your quest.

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
}