[SOLVED]Need help to convert System.Net.Http related code to UnityWebRequest Post Method

Unity Engine
1

Hi, I´m experimenting with API calls from an crypto exchange, here are the related c# examples:

I got the PUBLIC API part working. I can do the stuff with the request in the PRIVATE API part, but I have problems creating the authorization header correctly because of some features which won´t work inside UNITY, also I´m very confused how to convert this part.

the code example from the site:

string apiKey = "my key";
string apiSecret = "my secret";
string requestUri = "https://www.cryptopia.co.nz/Api/GetBalance";
var postData = new
{
    Currency = "DOT"
};

// Create Request
var request = new HttpRequestMessage();
request.Method = HttpMethod.Post;
request.RequestUri = new Uri(requestUri);
request.Content = new ObjectContent(typeof(object), postData, new JsonMediaTypeFormatter());

// Authentication
string requestContentBase64String = string.Empty;
if (request.Content != null)
{
   // Hash content to ensure message integrity
   using (var md5 = MD5.Create())
   {
      requestContentBase64String = Convert.ToBase64String(md5.ComputeHash(await request.Content.ReadAsByteArrayAsync()));
   }
}

//create random nonce for each request
var nonce = Guid.NewGuid().ToString("N");

//Creating the raw signature string
var signature = Encoding.UTF8.GetBytes(string.Concat(apiKey, HttpMethod.Post, HttpUtility.UrlEncode(request.RequestUri.AbsoluteUri.ToLower()), nonce, requestContentBase64String));
using (var hmac = new HMACSHA256(Convert.FromBase64String(apiSecret)))
{
   request.Headers.Authorization = new AuthenticationHeaderValue("amx", string.Format("{0}:{1}:{2}", apiKey, Convert.ToBase64String(hmac.ComputeHash(signature)), nonce));
}


// Send Request
using (var client = new HttpClient())
{
   var response = await client.SendAsync(request);
   if (response.IsSuccessStatusCode)
   {
      Console.WriteLine(await response.Content.ReadAsStringAsync());
      //{"Success":true,"Error":null,"Data":[{"CurrencyId":2,"Symbol":"DOT","Total":9646.07411016,"Available":9646.07411016,"Unconfirmed":0.0,"HeldForTrades":0.0,"PendingWithdraw":0.0,"Address":"1HEfio1kreDBgj5uCw4VHbEDSgc6YJXfTN","Status":"OK","StatusMessage":null}]}
   }
}

my code looks like this:

void Start()
    {
        var postData = new
        {
            Currency = "DOT"
        };
        StartCoroutine(postRequest("http://www.cryptopia.co.nz/api/GetBalance", postData.ToString()));
}

IEnumerator postRequest(string url, string json)
   {
        var uwr = new UnityWebRequest(url, "POST");
        byte[] bodyRaw = Encoding.UTF8.GetBytes(json);
        string requestContentBase64String = string.Empty;
        var md5 = MD5.Create();
        requestContentBase64String = Convert.ToBase64String(md5.ComputeHash(bodyRaw));

        var nonce = Guid.NewGuid().ToString("N");
        var signature = Encoding.UTF8.GetBytes(string.Concat(apiKey, UnityWebRequest.Post, UnityWebRequest.UrlEncode(url.ToLower()), nonce, requestContentBase64String));
        using (var hmac = new HMACSHA256(Convert.FromBase64String(apiSecret)))
        {
            uwr.SetRequestHeader("amx", string.Format("{0}:{1}:{2}", apiKey, Convert.ToBase64String(hmac.ComputeHash(signature)), nonce));
        }
        uwr.uploadHandler = (UploadHandler)new UploadHandlerRaw(bodyRaw);
        uwr.downloadHandler = (DownloadHandler)new DownloadHandlerBuffer();

        //Send the request then wait here until it returns
        yield return uwr.Send();

        if (uwr.isNetworkError)
        {
            Debug.Log("Error While Sending: " + uwr.error);
        }
        else
        {
            Debug.Log("Received: " + uwr.downloadHandler.text);
        }
   }

I´m really sure that this is tollay wrong because it gives me a “succesful= false error”
I think i have to use the WWW method to define the correct authorization header of Unity, but how?

APIKEY and APISECRET are the API key and PW creatd by the plattform…

2

Authentication:
Authenticated methods require the use of an api key and can only be accessed via the POST method.
Authorization is performed by sending the following variables into the request authentication header:

Authentication Method:
SCHEME: ‘amx’
PARAMETER: ‘API_KEY + ‘:’ + REQUEST_SIGNATURE + ‘:’ + NONCE’ signed by secret key according to HMAC-SHA256 method.

Request Structure:
REQUEST_SIGNATURE: API_KEY + “POST” + URI + NONCE + HASHED_POST_PARAMS
API_KEY: Your Cryptopia api key
URI: the request uri. e.g. https://www.cryptopia.co.nz/Api/SubmitTrade
HASHED_POST_PARAMS: Base64 encoded MD5 hash of the post parameters
NONCE: unique indicator for each request.

This is the part from the tutorial…

3

Ok, I´ve found a solution using this

there is a API.CS which provides everything I needed to do this…