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WebService Call from .net C# getting error : (502) Bad Gateway

Trying to call WebServices from C# and getting below error:
System.Net.WebException: 'The remote server returned an error: (502) Bad Gateway
Code:
WebRequest request = WebRequest.Create("https://xxxxx/cgi/webservice.pl?function=get_latest_ts_values&site_list=130105B&datasource=AT&varfrom=10.00&varto=10.00&lookback=60&format=csv");
request.Method = "GET";
WebResponse response = request.GetResponse();
using (Stream dataStream = response.GetResponseStream() )
{
StreamReader reader = new StreamReader(dataStream);
string responseFromServer = reader.ReadToEnd();
Console.WriteLine(responseFromServer);
Console.ReadLine();
}
But works fine when i use Postman or just copy url in browser and also works fine with below python code:
import requests
dataload = {}
dataurl = "https://xxxxx/cgi/webservice.pl?function=get_latest_ts_values&site_list=130105B&datasource=AT&varfrom=10.00&varto=10.00&lookback=60"
headers = {}
response = requests.request("GET", dataurl, headers=headers, data=dataload)
for dataresp in response:
print(dataresp)
What am I doing wrong with C# code?

The uri for the WebRequest has the query parameter &format=csv. Maybe this is why you are getting a 502. The Python request is missing that query parameter. Did you try the WebRequest by removing that part?

Could be incorrect content type or user agent having the wrong information. Postman could be setting these values without your knowledge. Might try in the exception seeing if there is a a response stream and read it through a streamreader to see if there is any more information you're not seeing to point you in the correct direction.

Ended up using RestSharp and it works fine. (https://www.nuget.org/packages/RestSharp)
string Uri = "https://xxxx/cgi/webservice.pl?xxxx";
var client = new RestSharp.RestClient(Uri);
client.Timeout = -1;
var request = new RestRequest(Method.GET);
IRestResponse response = client.Execute(request);
Console.WriteLine(response.Content);

POST json in C# return number

I have a problem with the POST method. I have a REST server programmed in C#, and I want to consume this REST service in C#, but I don't know how. The problem is that my method accepts a POST, receives a JSON payload and returns an HTTPStatusCode and a number:
id_task= planificadorService.CreaTarea(tareaDTO);//tareaDTO is a JSON
if (id_tarea == 0)
{
response = Request.CreateResponse(HttpStatusCode.NotFound, "Cannot create task ");
return response;
}
response = Request.CreateResponse(HttpStatusCode.Created);
response.Content = new StringContent(JsonConvert.SerializeObject(id_task), Encoding.UTF8, "application/json");
return response;
It was easy to do it using the GET method with the WebRequest and HttpWebResponse classes, but I don't know how to do it with the POST method. After many attempts, I ended up with something like this:
public void PostTareas(Tarea tarea)
{
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url_base + "/v1/tareas");
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "POST";
string json = JsonConvert.SerializeObject(tarea);
var client = new HttpClient()
{
BaseAddress = new Uri(url_base + "/v1/tareas")
};
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response;
response.Content= new StringContent(JsonConvert.SerializeObject(tarea).ToString(), Encoding.UTF8, "application/json");
response = client.PostAsync(url_base + "/v1/tareas", json)).Result;
}
I'm on the right track? How can I do this so that I am able to access the Json content? Thanks
P.D- Excuse my english, it is not my native language and I know there may be faults in expressing myself

With WebRequest you need to write the JSON in the POST request payload, use WebRequest.GetRequestStream:
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url_base + "/v1/tareas");
...
using(var requestStream = request.GetRequestStream()) {
// Write the serialized json into the stream, it will be send as payload
using(TextWriter writer = new StreamWriter(requestStream)) {
writer.WriteLine(JsonConvert.Serialize(tarea));
}
}
var response = request.GetResponse();
or you can use HttpClient and call PostAsync, as you're doing in your second part of your code. Either way is fine, but stick to one :)
You should also consider using a high(er) level library, like RestSharp. Ultimately consider exposing your server API with Swagger via Swashbuckle, generate a client with swagger-codegen and spend your time at the higher level abstraction of the API, not the HTTP/Json layer.

Calling Eventbrite API from .Net results in 401

I am trying to retrieve an order from the Eventbrite API. I have a valid OAuth token and order number. I have verified this by using postman which successfully returns the correct JSON.
However when I make the call using the following c# code, I get a 401 Unauthorised:
var client = new HttpClient();
var req = new HttpRequestMessage(HttpMethod.Get, "https://www.eventbriteapi.com/v3/orders/{orderNo}");
req.Headers.Add("Authorization", "Bearer {authToken}");
var response = await client.SendAsync(req);
I've tried replacing the header with:
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("{authToken}");
I have also tried:
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://www.eventbriteapi.com/v3/orders/{orderNo}");
request.Headers.Add("Authorization", "Bearer {authToken}");
request.Accept = "application/json";
using(WebResponse response = request.GetResponse())
{
using(Stream dataStream = response.GetResponseStream())
{
using(StreamReader reader = new StreamReader(dataStream))
{
string responseFromServer = reader.ReadToEnd();
}
}
}
All of these get a 401 response.
I know the authtoken and the eventid are correct, so there must be something wrong with my code.
Am I doing something wrong with the authroisation token?

Have you tried ?token={authToken} option on the EventBrite API?
This would at least confirm if it's a problem with the way the header is being sent across.
http://developer.eventbrite.com/docs/auth/

You omitted the trailing '/' in the URL, which caused a subsequent redirect from "eventbriteapi.com/v3/orders/{orderNo}" to "eventbriteapi.com/v3/orders/{orderNo}/". The authorization header was dropped in the redirect.

Omit images from webpage requested through HttpWebRequest

I fetch webpages in order to feed data to my application. However, the pages contain a lot of images which I don't require at all. I only need the text data.
My problem is that the web requests take an unacceptable amount of time. I think the images also are fetch during a web request. Is there any way to eliminate the images and download only the text data?
The following is the code that I am using currently.
var httpWebRequest = HttpWebRequest.Create(url) as HttpWebRequest;
httpWebRequest.Method = "GET";
httpWebRequest.ProtocolVersion = HttpVersion.Version11;
httpWebRequest.Headers.Add(HttpRequestHeader.AcceptEncoding, "gzip,deflate");
httpWebRequest.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
httpWebRequest.Proxy = null;
httpWebRequest.KeepAlive = true;
httpWebRequest.Accept = "text/html";
string responseString = null;
var httpWebResponse = httpWebRequest.GetResponse() as HttpWebResponse;
using (var responseStream = httpWebResponse.GetResponseStream())
{
using (var streamReader = new StreamReader(responseStream))
{
responseString = streamReader.ReadToEnd();
}
}
Also, any other optimization suggestions are most welcome.

That is incorrect.
HttpWebRequest does not know anything about HTML or images; it just sends raw HTTP requests.
You can use Fiddler to see exactly what's going on.

HttpWebRequest has empty response requesting a search from Bing

I have the following code that sends a HttpWebRequest to Bing. When I request the url below though it returns what appears to be an empty response when it should be returning a list of results.
var response = string.Empty;
var httpWebRequest = WebRequest.Create("http://www.bing.com/search?q=stackoverflow&count=100") as HttpWebRequest;
httpWebRequest.Method = WebRequestMethods.Http.Get;
httpWebRequest.Headers.Add("Accept-Language", "en-US");
httpWebRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Win32)";
httpWebRequest.Headers.Add(HttpRequestHeader.AcceptEncoding, "gzip,deflate");
using (var httpWebResponse = httpWebRequest.GetResponse() as HttpWebResponse)
{
Stream stream = null;
using (stream = httpWebResponse.GetResponseStream())
{
if (httpWebResponse.ContentEncoding.ToLower().Contains("gzip"))
stream = new GZipStream(stream, CompressionMode.Decompress);
else if (httpWebResponse.ContentEncoding.ToLower().Contains("deflate"))
stream = new DeflateStream(stream, CompressionMode.Decompress);
var streamReader = new StreamReader(stream, Encoding.UTF8);
response = streamReader.ReadToEnd();
}
}
Its pretty standard code for requesting and receiving a web page. Any ideas why the response is empty? Thanks in advance.
EDIT I left off a query string parameter in the url. I also had &count=100 which I have now corrected. It seems to work for values of 50 and below but returns nothing when larger. This works ok when in the browser, but not for this web request.
It makes me think the issue is that the response is large and HttpWebResponse is not handling that for me the way I have it set up. Just a guess though.

This works just fine on my machine. Perhaps you are IP banned from Bing?

Your code works fine on my machine.
I suggest you get yourself a copy of Fiddler and examine the actual HTTP sesssion occuring. May be a proxy or firewall thing.