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View source headers to be sent / received in HttpResponseMessage / HttpRequestMessage (System.Net.Http, WebAPI)

It can be very useful to visually see the original Http Headers list that will actually be sent or received in the web page types HttpResponseMessage / HttpRequestMessage. I mean just a simple old line with every heading on a new line, exactly what is generated or received.

But, unfortunately, it does not look like any of these types allows you to simply see what is actually being generated. Instead, there are properties scattered all over the place. Some of the raw types are HttpResponseMessage / HttpRequestMessage themselves, some of them in the /request.Content.Headers answer (two do not repeat, the latter for those that are no longer considered properties, usually for custom headers), and possibly Cookies somewhere gets into your headlines. And visually getting these Header collection lists is also a pain, meaning you get a bunch of duplicate code for every such collection ... more mess.

But in the actual answer / request sent / received, there is no such separation, and just see all the Http headers. So did I miss him somewhere? Is there really a simple and intuitive property that just returns a string of source headers? Of course, the answer has already received the headers and just analyzed them ... is this a hidden line somewhere?

(By the way, I know about Fiddler ... and this is completely unsatisfactory. If I have to deal with low-level messing of Http headers, then it makes sense to be able to view them with the program type I use to create and receive them. But worse, I’m all I still can not get localhost to work with Fiddler (on Win8), which makes it invalid for many debugging scenarios, where all I want to do is see the smelly headers that will be generated.)

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3 answers

I did not find a way to get the raw value of the request headers, but this code returns all the header values ​​(not in the original order):

request.Headers.ToString() + request.Content.Headers.ToString()
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, HttpRequestMessage.ToString (, , , , , ). , , ToString, . , , ToString:

var values = new JObject();

foreach (var raw_header in request.Headers
                                   .ToString()
                                   .Split(new[] { "\r\n" }, StringSplitOptions.RemoveEmptyEntries))
{
    var index = raw_header.IndexOf(':');
    if (index <= 0)
        continue;

    var key = raw_header.Substring(0, index);
    var value = index + 1 >= raw_header.Length ? string.Empty : raw_header.Substring(index + 1).TrimStart(' ');

    values.Add(new JProperty(key, value));
}
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Here is the code I use to catch the Request and Response headers:

* This is taken from a Windows Forms application, therefore: txtReceived and txtSent are simple multi-line text fields in the form of WindowsForms. and the cursor is the shape cursor. *

    private HttpClient PrepareHttpClient()
    {
        var client = new HttpClient();

        client.DefaultRequestHeaders.Accept.Add(
            new MediaTypeWithQualityHeaderValue("application/xml"));

        return client;
    }

    private string SendGetRequest(string url)
    {
        //Please be patient ...
        this.Cursor = Cursors.WaitCursor;

        var client = PrepareHttpClient();
        txtSent.Text = url;
        var taskReult = client.GetAsync(new Uri(url));
        HttpResponseMessage httpResponse = taskReult.Result;

        Stream st = httpResponse.Content.ReadAsStreamAsync().Result;
        StreamReader reader = new StreamReader(st);
        string content = reader.ReadToEnd();

        //Reset the cursor shape
        this.Cursor = Cursors.Default;

        txtReceived.Text = FormatResponse(httpResponse, content);

        //For GET we expect a response of 200 OK
        if (httpResponse.StatusCode == HttpStatusCode.OK)
        {
            return content;
        }

        throw new ApplicationException(content);
    }
    /// <summary>
    /// Post to the server using JSON
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="url">The server uri</param>
    /// <param name="e">The object to POST</param>
    /// <returns></returns>
    private string SendPostRequest<T>(string url, T e)
    {
        this.Cursor = Cursors.WaitCursor;
        HttpClient client = new HttpClient();

        // Create the JSON formatter.
        MediaTypeFormatter jsonFormatter = new JsonMediaTypeFormatter();

        // Use the JSON formatter to create the content of the request body.
        HttpContent content = new ObjectContent<T>(e, jsonFormatter);
        Stream st = content.ReadAsStreamAsync().Result;
        StreamReader reader = new StreamReader(st);
        string s = reader.ReadToEnd();


        // Send the request.
        var taskResult = client.PostAsync(url, content);

        //Note: We could simply perform the following line and save some time
        //but then we will not have access to the post content:
        //var taskResult = client.PostAsJsonAsync<T>(url, e);

        HttpResponseMessage httpResponse = taskResult.Result;
        this.Cursor = Cursors.Default;

        txtSent.Text = FormatRequest(httpResponse.RequestMessage, s);

        st = httpResponse.Content.ReadAsStreamAsync().Result;
        reader = new StreamReader(st);
        string responseContent = reader.ReadToEnd();
        txtReceived.Text = FormatResponse(httpResponse, responseContent);

        //For POST we expect a response of 201 Created
        if (httpResponse.StatusCode == HttpStatusCode.Created)
        {
            return responseContent;
        }

        throw new ApplicationException(responseContent);
    }

    /// <summary>
    /// PUT to the server using JSON
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="url"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private string SendPutRequest<T>(string url, T e)
    {
        this.Cursor = Cursors.WaitCursor;
        HttpClient client = new HttpClient();

        // Create the JSON formatter.
        MediaTypeFormatter jsonFormatter = new JsonMediaTypeFormatter();

        // Use the JSON formatter to create the content of the request body.
        HttpContent content = new ObjectContent<T>(e, jsonFormatter);
        Stream st = content.ReadAsStreamAsync().Result;
        StreamReader reader = new StreamReader(st);
        string s = reader.ReadToEnd();

        // Send the request.
        var taskResult = client.PutAsync(url, content);

        //Note: We could simply perform the following line and save some time
        //but then we will not have access to the post content:
        //var taskResult = client.PutAsJsonAsync<T>(url, e);

        HttpResponseMessage httpResponse = taskResult.Result;

        txtSent.Text = FormatRequest(httpResponse.RequestMessage, s);

        st = httpResponse.Content.ReadAsStreamAsync().Result;
        reader = new StreamReader(st);
        string responseContent = reader.ReadToEnd();
        this.Cursor = Cursors.Default;
        txtReceived.Text = FormatResponse(httpResponse, responseContent);

        //For PUT we expect a response of 200 OK
        if (httpResponse.StatusCode == HttpStatusCode.OK)
        {
            return responseContent;
        }

        throw new ApplicationException(responseContent);
    }

    private string FormatRequest(HttpRequestMessage request, string content)
    {
        return
            string.Format("{0} {1} HTTP/{2}\r\n{3}\r\n{4}",
                request.Method,
                request.RequestUri,
                request.Version,
                request.Headers,
                content);
    }

    private string FormatResponse(HttpResponseMessage result, string content)
    {
        return
            string.Format("HTTP/{0} {1} {2}\r\n{3}\r\n{4}",
                result.Version,
                (int)result.StatusCode,
                result.ReasonPhrase,
                result.Headers,
                content);
    }
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