add Ndax rate provider

BTCPayServer.Rating/Providers/ByllsRateProvider.cs

@@ -1,6 +1,4 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
 using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;

BTCPayServer.Rating/Providers/NdaxRateProvider.cs

@@ -0,0 +1,36 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using BTCPayServer.Rating;
+using Newtonsoft.Json.Linq;
+
+namespace BTCPayServer.Services.Rates
+{
+    public class NdaxRateProvider : IRateProvider, IHasExchangeName
+    {
+        private readonly HttpClient _httpClient;
+
+        public NdaxRateProvider(HttpClient httpClient)
+        {
+            _httpClient = httpClient ?? new HttpClient();
+        }
+
+        public string ExchangeName => "ndax";
+
+        public async Task<ExchangeRates> GetRatesAsync(CancellationToken cancellationToken)
+        {
+            var response = await _httpClient.GetAsync("https://ndax.io/api/returnTicker", cancellationToken);
+            var jobj = await response.Content.ReadAsAsync<Dictionary<string, JObject>>(cancellationToken);
+            return new ExchangeRates(jobj.Select(pair => new ExchangeRate(ExchangeName, CurrencyPair.Parse(pair.Key),
+                new BidAsk(GetValue(pair.Value["highestBid"]), GetValue(pair.Value["lowestAsk"])))));
+        }
+
+        private static decimal GetValue(JToken jobj)
+        {
+            return string.IsNullOrEmpty(jobj.ToString()) ? 0 : jobj.Value<decimal>();
+        }
+
+    }
+}

BTCPayServer.Rating/Services/RateProviderFactory.cs

@@ -113,6 +113,7 @@ namespace BTCPayServer.Services.Rates
             Providers.Add(CoinAverageRateProvider.CoinAverageName, new CoinAverageRateProvider() { Exchange = CoinAverageRateProvider.CoinAverageName, HttpClient = _httpClientFactory?.CreateClient("EXCHANGE_COINAVERAGE"), Authenticator = _CoinAverageSettings });
             Providers.Add("kraken", new KrakenExchangeRateProvider() { HttpClient = _httpClientFactory?.CreateClient("EXCHANGE_KRAKEN") });
             Providers.Add("bylls", new ByllsRateProvider(_httpClientFactory?.CreateClient("EXCHANGE_BYLLS")));
+            Providers.Add("ndax", new NdaxRateProvider(_httpClientFactory?.CreateClient("EXCHANGE_NDAX")));
             Providers.Add("bitbank", new BitbankRateProvider(_httpClientFactory?.CreateClient("EXCHANGE_BITBANK")));
             Providers.Add("bitpay", new BitpayRateProvider(_httpClientFactory?.CreateClient("EXCHANGE_BITPAY")));
 
@@ -171,6 +172,7 @@ namespace BTCPayServer.Services.Rates
             // Add other exchanges supported here
             exchanges.Add(new CoinAverageExchange(CoinAverageRateProvider.CoinAverageName, "Coin Average", $"https://apiv2.bitcoinaverage.com/indices/global/ticker/short"));
             exchanges.Add(new CoinAverageExchange("bylls", "Bylls", "https://bylls.com/api/price?from_currency=BTC&to_currency=CAD"));
+            exchanges.Add(new CoinAverageExchange("ndax", "NDAX", "https://ndax.io/api/returnTicker"));
             exchanges.Add(new CoinAverageExchange("bitbank", "Bitbank", "https://public.bitbank.cc/prices"));
 
             return exchanges;