AdyenUrlManager:

-Updated Adyen api version to v71, and js/css version to 5.59.0.
-Added new template tags: Adyen.JsIntegrityKey, Adyen.CssIntegrityKey. Customer don't need to look at adyen documentation and search these values, since we use the specific js/css adyen version anyway and should provide integrity values also.
AdyenCheckout: Added processing of errors output.
Helper:
- Changed OutputResult of Helper.EndRequest to be StreamOutputResult. ContentOutputResult provides the html markup, and for these methods we need only json, since they are used in js-ajax fetches etc.
- Fixed little bug related with query string.
WebRequestHelper:
- Properly added NoCache header, removed Accept-Charset, since this is processing in StringContent.
- Added async reading to ReadRequestInputStream to fix the error.

src/AdyenCheckoutHandler.cs

@@ -31,6 +31,8 @@ private static class Tags
             public static string AmountValue = "Adyen.Price";
             public static string AdyenJavaScriptUrl = "Adyen.JavaScriptUrl";
             public static string AdyenCssUrl = "Adyen.CssUrl";
+            public static string AdyenJsIntegrityKey = "Adyen.JsIntegrityKey";
+            public static string AdyenCssIntegrityKey = "Adyen.CssIntegrityKey";
         }
 
         #region Fields
@@ -165,6 +167,8 @@ public override OutputResult BeginCheckout(Order order, CheckoutParameters param
             paymentMethodsTemplate.SetTag(Tags.AmountValue, order.Price.PricePIP);
             paymentMethodsTemplate.SetTag(Tags.AdyenCssUrl, ApiUrlManager.GetCssUrl());
             paymentMethodsTemplate.SetTag(Tags.AdyenJavaScriptUrl, ApiUrlManager.GetJavaScriptUrl());
+            paymentMethodsTemplate.SetTag(Tags.AdyenJsIntegrityKey, ApiUrlManager.JsIntegrityKey);
+            paymentMethodsTemplate.SetTag(Tags.AdyenCssIntegrityKey, ApiUrlManager.CssIntegrityKey);
 
             return new ContentOutputResult
             {
@@ -288,9 +292,13 @@ private OutputResult PaymentMethodSelected(Order order, PaymentMethodData paymen
             var paymentRequest = new PaymentRequest(order, paymentMethodData, MerchantName, GetCallbackUrl(order, new NameValueCollection { ["action"] = "GatewayResponse" }), additionalAction);
             try
             {
-                var paymentMethodsResponse = WebRequestHelper.Request(ApiUrlManager.GetPaymentUrl(), paymentRequest.ToJson(), GetEnvironmentType(), ApiKey);
-                var paymentResponse = Converter.Deserialize<PaymentResponse>(paymentMethodsResponse);
+                string paymentMethodsResponse = WebRequestHelper.Request(ApiUrlManager.GetPaymentUrl(), paymentRequest.ToJson(), GetEnvironmentType(), ApiKey);
+
+                var error = Converter.Deserialize<ServiceError>(paymentMethodsResponse);
+                if (!string.IsNullOrEmpty(error.ErrorCode))
+                    return OnError(order, $"Error code: {error.ErrorCode}. {error.Message}", null, Helper.IsAjaxRequest());
 
+                var paymentResponse = Converter.Deserialize<PaymentResponse>(paymentMethodsResponse);
                 return HandleAdyenPaymentResponse(order, paymentResponse, paymentMethodsResponse, doSaveCard, cardName, paymentMethodData.PaymentMethod.Type);
             }
             catch (Exception e) when (e is not ThreadAbortException)

src/AdyenUrlManager.cs

@@ -4,14 +4,18 @@ namespace Dynamicweb.Ecommerce.CheckoutHandlers.Adyen
 {
     internal class AdyenUrlManager
     {
-        private const string ApiVersion = "v70";
-        private const string JsCssVersion = "5.37.0";
+        private const string ApiVersion = "v71";
+        private const string JsCssVersion = "5.59.0";
 
         private EnvironmentType _environment;
         private string _liveEndpointUrlPrefix;
 
         private bool IsTest => _environment == EnvironmentType.Test;
 
+        public string JsIntegrityKey => "sha384-O8p0CLZyOw1jkmYN7ZwJxWzd+sDYRFGpLEffqc+dKye24gFImbU72did4PC7ysTY";
+
+        public string CssIntegrityKey => "sha384-zgFNrGzbwuX5qJLys75cOUIGru/BoEzhGMyC07I3OSdHqXuhUfoDPVG03G+61oF4";
+
         public AdyenUrlManager(EnvironmentType environment, string liveEndpointUrlPrefix)
         {
             _environment = environment;

src/Helper.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.Specialized;
+using System.IO;
 using System.Linq;
 using System.Security.Cryptography;
 using System.Text;
@@ -20,15 +21,13 @@ public static bool IsAjaxRequest()
             return "application/json".Equals(Context.Current.Request.Headers["Content-Type"], StringComparison.OrdinalIgnoreCase);
         }
 
-        public static ContentOutputResult EndRequest<T>(T obj) => EndRequest(Converter.SerializeCompact(obj));
+        public static StreamOutputResult EndRequest<T>(T obj) => EndRequest(Converter.SerializeCompact(obj));
 
-        public static ContentOutputResult EndRequest(string json)
+        public static StreamOutputResult EndRequest(string json) => new StreamOutputResult
         {
-            if (!string.IsNullOrEmpty(json))
-                return new() { Content = json };
-
-            return ContentOutputResult.Empty;
-        }
+            ContentStream = new MemoryStream(Encoding.UTF8.GetBytes(json ?? string.Empty)),
+            ContentType = "application/json"
+        };
 
         public static string GetCallbackUrl(string baseUrl, NameValueCollection parameters)
         {
@@ -40,7 +39,8 @@ public static string GetCallbackUrl(string baseUrl, NameValueCollection paramete
                 {
                     query[key] = parameters[key];
                 }
-                uriBuilder.Query = query.ToString();
+
+                uriBuilder.Query = string.Join("&", query.AllKeys.Select(key => $"{key}={query[key]}"));
             }
 
             return uriBuilder.Uri.ToString();

src/WebRequestHelper.cs

@@ -2,6 +2,7 @@
 using System.Linq;
 using System.Net;
 using System.Net.Http;
+using System.Net.Http.Headers;
 using System.Net.Security;
 using System.Security.Cryptography.X509Certificates;
 using System.Text;
@@ -29,9 +30,11 @@ public static string Request(string endpoint, string json, EnvironmentType envir
                 handler.ServerCertificateCustomValidationCallback = ServerCertificateValidationCallback;
                 using (var client = new HttpClient(handler))
                 {
+                    client.DefaultRequestHeaders.CacheControl = new CacheControlHeaderValue
+                    {
+                        NoCache = true
+                    };
                     var content = new StringContent(json, Encoding.UTF8, "application/json");
-                    content.Headers.Add("Accept-Charset", "UTF-8");
-                    content.Headers.Add("Cache-Control", "no-cache");
                     content.Headers.Add("x-api-key", apiKey);
                     using (HttpResponseMessage response = client.PostAsync(endpoint, content).GetAwaiter().GetResult())
                     {
@@ -52,7 +55,7 @@ public static string ReadRequestInputStream()
             {
                 using (var readStream = new StreamReader(receiveStream, Encoding.UTF8))
                 {
-                    return readStream.ReadToEnd();
+                    return readStream.ReadToEndAsync().GetAwaiter().GetResult();
                 }
             }
         }