HttpWebRequest, How to Send POST Data with Application/JSON Content-Type?

Question

HttpWebRequest request = (HttpWebRequest) HttpWebRequest.Create(url);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded; charset=utf-8";

POST data was send (I check using Fiddler) returned from Yahoo :

{"error":{"code":-1003,"detail":"Unsupported Content Type Error","description":"Unsupported Content Type Error"},"code":-1003}

I'm writing Yahoo Messanger client that require application/json; charset=utf-8 as content type, and when I set :

request.ContentType = "application/json; charset=utf-8";

No POST data send, returned from Yahoo :

{"error":{"code":-1005,"detail":"Invalid Argument Error","description":"Invalid Argument Error"},"code":-1005}

UPDATE

I was try to send this 2 values via POST method : presenceState & status.

As stated in Yahoo Messager IM API supported content-type are application/json. And in my code, if I set content-type to application/json, HttpWebRequest didn't send those 2 values via POST.

Cholecyst

Are you really sure that the request doesn't go out from your client, but fails at the server? – Masked

Using Fiddler, from my first code yahoo server return this JSON result : {"error":{"code":-1003,"detail":"Unsupported Content Type Error","description":"Unsupported Content Type Error"},"code":-1003}. And response code 400 (Bad Request). – Cholecyst

Answer 1

Take a look on following example

byte[] data = CreateData(value);
var requst = (HttpWebRequest) WebRequest.Create(uri);
requst.Method = "POST";
requst.ContentType = "application/json";
requst.ContentLength = data.Length;
using (Stream stream = requst.GetRequestStream())
{
    stream.Write(data, 0, data.Length);
}

Where CreateData is

public static byte[] Create<T>(T value)
{
    var serializer = new DataContractJsonSerializer(typeof (T));
    using (var stream = new MemoryStream())
    {
        serializer.WriteObject(stream, value);
        return stream.ToArray();
    }
}

Martinsen

Answer 2

I'm super late to the party, but I ended up here trying to figure out what I was messing up, so maybe this will help someone else.

If in your c# code you set your content type and then add some other headers-- something like this:

httpWebRequest.ContentType = @"application/json; charset=utf-8";        
WebHeaderCollection headers = new WebHeaderCollection();
headers.Add("Authorization", "Bearer "+oAuthBearerToken);
httpWebRequest.Headers = headers;

what's actually happening, is that when you write to .ContentType, under the hood it's setting Content-Type in your request's WebHeaderCollection. And then you go ahead and overwrite them. This could happen to any header you set like that before you add a bunch of custom ones. If this is what you're doing, just set the custom headers first, and then write to the .Whichever headers.

Remy

Answer 3

Based on your error, the first one is failing as the content type of the request doesn't match that of what Yahoo is expecting. This makes sense and your second example is going towards the right path, but based on your posting it seems you are getting a response. With fiddler you should be able to compare your posting with that of a proper request through the site. That might help pinpoint where it is going wrong.

But regardless we will need to be seeing a bit more of what you are doing as there is nothing showing hte contents of your post for us to review.

Hebbe

Thanks for your replay, I have edited my question, and add more info what I'm doing. – Cholecyst

Answer 4

i was struggling with the exact same issue. as noted in the documentation (http://developer.yahoo.com/messenger/guide/ch01s04.html), you need to have an empty body ({}) in the POST request.

using javascript & jQuery, i sent a simple empty object string in the POST body, and that works:

    $.ajax({
        type: 'POST',
        url: 'http://developer.messenger.yahooapis.com/v1/session',
        data: JSON.stringify({ }),
        processData: false,
        beforeSend: function(xhr) {
            xhr.setRequestHeader('Authorization', OAuth.getAuthorizationHeader("yahooapis.com", message.parameters));
            xhr.setRequestHeader('Content-Type','application/json; charset=UTF-8');
            xhr.setRequestHeader('X-Yahoo-Msgr-User-Agent','YahooMessenger/1.0 (yourapp; 1.0.0.1)')
        }});

hope that helps.

Oneidaoneil

Answer 5

My error maybe is the same your error. The problem is resolved by change type of presenceState to int type not string type.

ClassLogon objLogon = new ClassLogon
  {
    presenceState = ***0***,
    presenceMessage = "I am logn"
  };

I hope you resolve this.

Iny

Thanks for your replay, do you use HttpWebRequest and what setting to you use ? And can you share your code ? – Cholecyst