I am sending http request to sandbox api which sometimes returns positive response but sometimes it returns bad request with same request data and headers. So I want to debug this request using fiddler during I run the .net core code hitting that api.
But I am not able to find any way to that. Can any one please help me out for the same. I have tried following code to do this:
var requestMessage = GenerateRequestMessage(HttpMethod.Put, uri, query);
requestMessage.Content = new ObjectContent<T>(value, new JsonMediaTypeFormatter(), (MediaTypeHeaderValue)null);
IWebProxy proxy = new WebProxy("127.0.0.1", 8888);
HttpClient.DefaultProxy = proxy;
return _httpClient.SendAsync(requestMessage);
but fiddler is not capturing this api request.
Related
I have a requirement where I would need to call a servlet end point.
The servlet does the huge task. It might take about hours to do task.
Keeping all these, I need to build a http client which keeps connection and call this end point. I am not interested in the response. It should just call the endpoint and forget. Which client should i use ?
I tried with apache http client
CloseableHttpAsyncClient httpclient = HttpAsyncClients.createDefault();
httpclient.start();
HttpGet request = new HttpGet(URL);`
Future<HttpResponse> future = httpclient.execute(request,null);
Does this call the end point of the servlet, because I don't see any logs of the servlet endpoint.
HttpResponse response = future.get();
Is this line required ? As I don't need to capture response.
No, it is not needed. The line:
HttpResponse response = future.get();
blocks your thread until the there is a HTTP response or connection breaks. Check out Future.get() javadoc
Im using the following AJAX request to send request to New Relic, however its always throws "404 Not Found" error.
Following is the code:
var client = new XMLHttpRequest();
client.open("GET", "https://insights-api.newrelic.com/v1/accounts/REMAINING.URL", true);
client.setRequestHeader("Accept", "application/json");
client.setRequestHeader("X-Query-Key", "QUERY.KEY");
client.send();
Since the origin of the XMLHttpRequest (XHR) or Ajax is different to the requested API's URL, Cross-origin resource sharing (CORS) prevents from accessing the API. Hence, this doesn't work. To implement this, the API will have to be requested by the back-end via .NET, JAVA, PHP, Python, etc. any server side technology and the result will have to be sent to the client Ajax calls.
Have an ASP.NET Web API endpoint that generates JSON responses. But due to two factors can't be consumed directly from a browser.
cross-domain issues
need to provide session ticket for the API that is known only server side
So I need a lightweight server side proxy for client(browser) requests to extend the request with session key. Do not want to impose an overhead deserializing client JSON requests or Web API JSON responses in the proxy code. Would like to pass the payload "as is" and deserialize client requests only Web API side and the Web API responses only client (browser) side. That is the proxy takes json from the browser and passes it directly to Web API. It also passes the JSON response from the Web API to the browser directly without deserialization. Just a dummy proxy that does not know anything about the data it transfers.
Please suggest is it feasible and what is the best way to implement it. The existing web application (the one that is used to generate the client pages) is implemented using ASP.NET MVC 4.
Thanks in advance.
update for 2021:
You should probably be looking at https://microsoft.github.io/reverse-proxy/ if you have found your way here
old answer:
I wrote one for a previous version of WebApi. The code should be fairly easy to update for your purposes.
The basic idea is that you create a WebApi DelegatingHandler that passes the request on to an HttpClient:
public class ForwardProxyMessageHandler : DelegatingHandler
{
protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
request.Headers.Add("X-Forwarded-For", request.GetClientIp());
if (request.Method == HttpMethod.Get || request.Method == HttpMethod.Trace) request.Content = null;
request.RequestUri = new Uri(request.RequestUri.ToString().Replace(":3002", "")); //comes through with the port for the proxy, rewrite to port 80
request.Headers.AcceptEncoding.Clear();
var responseMessage = await new HttpClient().SendAsync(request, HttpCompletionOption.ResponseHeadersRead);
responseMessage.Headers.TransferEncodingChunked = null; //throws an error on calls to WebApi results
if (request.Method == HttpMethod.Head) responseMessage.Content = null;
return responseMessage;
}
}
I am running a very simple Web application (Asp.Net MVC3) on Win 7 IIS.
I have a very simple HTTP GET API which returns hello world.
Calling:
http://localhost/helloworld
Returns:
Hello World!
This works perfectly over a browser.
But when I write an app which tries to pull this URL using a webclient, I get the following error:
{"Unable to read data from the transport connection: The connection was closed."}
My Code is as follows
WebClient web = new WebClient();
var response = web.DownloadString("http://localhost/helloworld");
My IIS Settings are as follows
What should I be looking at? I have been at this for hours and I have run out of options to try! Any help will be really appreciated!
Thanks.
I suspect it's because WebClient does not send some of the HTTP headers:
A WebClient instance does not send optional HTTP headers by default. If your request requires an optional header, you must add the header to the Headers collection. For example, to retain queries in the response, you must add a user-agent header. Also, servers may return 500 (Internal Server Error) if the user agent header is missing. http://msdn.microsoft.com/en-us/library/system.net.webclient(v=vs.80).aspx
Try using HttpWebRequest instead. http://msdn.microsoft.com/en-us/library/system.net.httpwebrequest.aspx
I finally figured out what the issue was and instead of it being an IIS specific issue - which I was leaning towards, it turned out to be an issue with the code that I wrote.
Adding details here incase someone else runs into a similar problem.
I had the following method in my code which I was using to send the response of the request as a JSON object.
private void sendJsonResult(string result) {
Response.StatusCode = 200;
Response.Headers.Add("Content-Type", "application/json; charset=utf-8");
Response.Flush();
Response.Write(result);
Response.End();
Response.Close(); // <-- This is the problem statement
}
On digging around a bit, I found out that we should not be doing a Response.Close().
A better explanation of this is here.
Once I removed that line, it started working perfectly - both in my consuming app as well as the web browser, etc.
If you will read the link above, you will clearly understand why we should not be using a Response.Close() - so I will not go into that description. Learnt a new thing today.
I am connecting to a service using a HttpWebRequest. In the service logs, there are Authentication errors being logged, even though the information is correct. The vendor who set up the server with the service, has said that .NET does not send the authentication headers on the first try.
_Req.Credentials = new NetworkCredential(username, password);
When the request is sent, the server responds with needing the headers, which the request then sends. Is this correct, and is there a way to send it on the initial request?
See this question pointing to the answer in this article: add headers manually (even the first time).
HttpWebRequest request;
request.PreAuthenticate = true;