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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;
}

Trying to upload with a PUT request

I am trying to change the price of an article using the websites API
the documentation for it is at https://www.mkmapi.eu/ws/documentation/API_1.1:Stock
When run the class I get an error 417 Expectation Failed, which is described from the documentation as:
Typically you get a 417 Expectation Failed HTTP status code, when your request has an XML body without the corresponding header and/or the body not sent as text, but its byte representation. Another possible reason for a 417 is, when you send body data with more than 1.024 bytes without adding the header Expect: to your request.
Any help would be appreciated. I should also say that the authentication is not the problem I can download my article prices.
public void UpdateMarketPrice(string MarketID, string NewPrice)
{
// https://www.mkmapi.eu/ws/documentation/API_1.1:Stock
String finalResult;
String method = "PUT";
String url = "https://www.mkmapi.eu/ws/v1.1/stock";
HttpWebRequest request = WebRequest.CreateHttp(url) as HttpWebRequest;
OAuthHeader header = new OAuthHeader();
request.Headers.Add(HttpRequestHeader.Authorization, header.getAuthorizationHeader(method, url));
request.Method = method;
request.ContentType = "text/xml; encoding='utf-8'";
XElement xmlDoc =
new XElement("request",
new XElement("article",
new XElement("idArticle", MarketID),
new XElement("idLanguage", 1),
new XElement("comments", "Edited through the API"),
new XElement("count", 7),
new XElement("price", 11),
new XElement("condition", "NM"),
new XElement("isFoil", false),
new XElement("isSigned", false),
new XElement("isPlayset", false)
)
);
String finalXML = "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n" + xmlDoc.ToString();
MessageBox.Show(finalXML);
byte[] bytes = Encoding.ASCII.GetBytes(finalXML);
request.ContentLength = bytes.Length;
using (Stream putStream = request.GetRequestStream())
{
putStream.Write(bytes, 0, bytes.Length);
}
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
finalResult = reader.ReadToEnd();
}
MessageBox.Show(finalResult);
}

I have read that HttpWebRequest adds an "expect 100 continue" header to requests unless you turn it off. There are servers that possibly don't support this header. And will produce this 417 Expectation Failed message.
You could try setting it to false:
System.Net.ServicePointManager.Expect100Continue = false;
So the header isn't sent.
I've seen this suggested sollution to other similar questions also.

Maybe use StreamWriter ?
using (Stream putStream = request.GetRequestStream())
{
using (var writeStream = new StreamWriter(putStream, Encoding.ASCII))
{
writeStream.Write(finalXML);
}
request.ContentLength = putStream.Length; // I am not sure about that
}

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;

How to ignore 401 and continue to read feeds

I was given a json feed.
It does not need any user name or password to access.
It can be seen from google Chrome.
In the google Chrome developer tool, it also say status 401,
but still able to read data.
Then I try to use C# web request or webclient, i get 401 and thrown , no longer able to continue.
So how does Chrome do it? and what should i do?
My C# code:
WebRequest request = WebRequest.Create(url);
request.UseDefaultCredentials = true;
request.Method = WebRequestMethods.Http.Get;
((HttpWebRequest)request).UserAgent = userAgent;
request.Timeout = timeOut;
((HttpWebRequest)request).Accept = "application/json";
response = request.GetResponse();
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream, Encoding.UTF8);

You can "catch" the 401 exception that is thrown by HttpWebRequest and read the content off the WebException using code like this:
try {
// your code above
}
catch(Exception oEx)
{
if(oEx.GetType() == typeof(WebException))
{
HttpWebResponse wr = ((WebException)oEx).Response as HttpWebResponse;
Stream dataStream = wr.GetResponseStream();
StreamReader reader = new StreamReader(dataStream, Encoding.UTF8);
string str = reader.ReadToEnd(); // str will contain the body of the HTTP 401 response
reader.Close();
}
}

Getting (500) Internal Server Error when calling restful webservice

When i run the below code I am getting error like ex = {"The remote server returned an error: (500) Internal Server Error."} can anyone help me how to fix this issue...
HttpWebRequest request = WebRequest.Create("http://project.i-engage.org/tasks/webservices/bugnetservices.asmx/GetCategories?ProjectID=17") as HttpWebRequest;
request.Credentials = new NetworkCredential("rolland", "409cleaner");
request.ContentType = "application / json; charset = utf - 8";
request.Method = "POST";
using (Stream stm = request.GetRequestStream())
{
using (StreamWriter stmw = new StreamWriter(stm))
{
stmw.Write(soap);
}
}
// Get response
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
// Get the response stream
StreamReader reader = new StreamReader(response.GetResponseStream());
// Console application output
Console.WriteLine(reader.ReadToEnd());
}

its problem with webservice...they are not returning auth cookie.. now its working fine.