ASP.NET MVC - Using cURL or similar to perform requests in application

Question

I'm building an application in ASP.NET MVC (using C#) and I would like to know how I can perform calls like curl http://www.mywebsite.com/clients_list.xml inside my controller Basically I would like to build a kind of REST API to perform actions such as show edit and delete, such as Twitter API.

But unfortunately until now I didn't find anything besides that cURL for windows on this website: http://curl.haxx.se/

So I don't know if is there any traditional way to retrieve this kind of call from URL with methods like post delete and put on the requests, etc...

I just would like to know an easy way to perform commands like curl inside my controller on my ASP.NET MVC Application.

---

UPDATE:

Hi so I managed to make GET Requests but now I'm having a serious problem in retrieve POST Request for example, I'm using the update status API from Twitter that in curl would work like this:

curl -u user:password -d "status=playing with cURL and the Twitter API" http://twitter.com/statuses/update.xml

but on my ASP.NET MVC application I'm doing like this inside my custom function:

string responseText = String.Empty;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://twitter.com/statuses/update.xml");
request.Method = "POST";
request.Credentials = new NetworkCredential("username", "password");
request.Headers.Add("status", "Tweeting from ASP.NET MVC C#");
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
using (StreamReader sr = new StreamReader(response.GetResponseStream()))
{
    responseText = sr.ReadToEnd();
}
return responseText;

Now the problem is that this request is returning 403 Forbidden, I really don't know why if it works perfectly on curl

:\

---

UPDATE:

I finally manage to get it working, but probably there's a way to make it cleaner and beautiful, as I'm new on C# I'll need more knowledge to do it, the way the POST params are passed makes me very confused because is a lot of code to just pass params.

Well, I've created a Gist - http://gist.github.com/215900 , so everybody feel free to revise it as you will. Thanks for your help çağdaş

also follow the code here:

public string TwitterCurl()
{
    //PREVENT RESPONSE 417 - EXPECTATION FAILED
    System.Net.ServicePointManager.Expect100Continue = false;

    HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://twitter.com/statuses/update.xml");
    request.Method = "POST";
    request.Credentials = new NetworkCredential("twitterUsername", "twitterPassword");

    //DECLARE POST PARAMS
    string headerVars = String.Format("status={0}", "Tweeting from ASP.NET MVC C#");
    request.ContentLength = headerVars.Length;

    //SEND INFORMATION
    using (StreamWriter streamWriter = new StreamWriter(request.GetRequestStream(), ASCIIEncoding.ASCII))
    {
        streamWriter.Write(headerVars);
        streamWriter.Close();
    }

    //RETRIEVE RESPONSE
    string responseText = String.Empty;
    using (StreamReader sr = new StreamReader(request.GetResponse().GetResponseStream()))
    {
        responseText = sr.ReadToEnd();
    }

    return responseText;

    /*
    //I'M NOT SURE WHAT THIS IS FOR            
        request.Timeout = 500000;
        request.ContentType = "application/x-www-form-urlencoded";
        request.UserAgent = "Custom Twitter Agent";
        #if USE_PROXY
            request.Proxy = new WebProxy("http://localhost:3000", false);
        #endif
    */
}

Answer 1

Try using Microsoft.Http.HttpClient. This is what your request would look like

var client = new HttpClient();
client.DefaultHeaders.Authorization = Credential.CreateBasic("username","password");

var form = new HttpUrlEncodedForm();
form.Add("status","Test tweet using Microsoft.Http.HttpClient");
var content = form.CreateHttpContent();

var resp = client.Post("http://www.twitter.com/statuses/update.xml", content);
string result = resp.Content.ReadAsString();

You can find this library and its source included in the WCF REST Starter kit Preview 2, however it can be used independently of the rest of the stuff in there.

P.S. I tested this code on my twitter account and it works.

Answer 2

Example code using HttpWebRequest and HttpWebResponse :

public string GetResponseText(string url) {
    string responseText = String.Empty;
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
    request.Method = "GET";
    HttpWebResponse response = (HttpWebResponse)request.GetResponse();
    using (StreamReader sr = new StreamReader(response.GetResponseStream())) {
        responseText = sr.ReadToEnd();
    }
    return responseText;
}

To POST data :

public string GetResponseText(string url, string postData) {
    string responseText = String.Empty;
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
    request.Method = "POST";
    request.ContentLength = postData.Length;
    using (StreamWriter sw = new StreamWriter(request.GetRequestStream())) {
        sw.Write(postData);
    }
    HttpWebResponse response = (HttpWebResponse)request.GetResponse();
    using (StreamReader sr = new StreamReader(response.GetResponseStream())) {
        responseText = sr.ReadToEnd();
    }
    return responseText;
}

Answer 3

This is the single line of code I use for calls to a RESTful API that returns JSON.

return ((dynamic) JsonConvert.DeserializeObject<ExpandoObject>(
        new WebClient().DownloadString(
            GetUri(surveyId))
    )).data;

Notes

• The Uri is generated off stage using the surveyId and credentials
• The 'data' property is part of the de-serialized JSON object returned by the SurveyGizmo API

The Complete Service

public static class SurveyGizmoService
{
    public static string UserName { get { return WebConfigurationManager.AppSettings["SurveyGizmo.UserName"]; } }
    public static string Password { get { return WebConfigurationManager.AppSettings["SurveyGizmo.Password"]; } }
    public static string ApiUri { get { return WebConfigurationManager.AppSettings["SurveyGizmo.ApiUri"]; } }
    public static string SurveyId { get { return WebConfigurationManager.AppSettings["SurveyGizmo.Survey"]; } }

    public static dynamic GetSurvey(string surveyId = null)
    {
        return ((dynamic) JsonConvert.DeserializeObject<ExpandoObject>(
                new WebClient().DownloadString(
                    GetUri(surveyId))
            )).data;
    }

    private static Uri GetUri(string surveyId = null)
    {
        if (surveyId == null) surveyId = SurveyId;
        return new UriBuilder(ApiUri)
                {
                        Path = "/head/survey/" + surveyId,
                        Query = String.Format("user:pass={0}:{1}", UserName, Password)
                }.Uri;
    }
}

Answer 4

Look into the System.Net.WebClient class. It should offer the functionality you require. For finer grained control, you might find WebRequest to be more useful, but WebClient seems the best fit for your needs.