Add signature handling for dLocal API requests (#485)

Author: armando-rodriguez-cko

src/CheckoutSdk/Forward/Requests/DestinationRequest.cs

@@ -1,3 +1,5 @@
+using Checkout.Forward.Requests.Signatures;
+
 namespace Checkout.Forward.Requests
 {
     public class DestinationRequest
@@ -17,5 +19,10 @@ public class DestinationRequest
         ///     payment instrument you specified. For example, {{card_number}} (Required, max 16384 characters)
         /// </summary>
         public string Body { get; set; }
+        
+        /// <summary>
+        ///     Optional configuration to add a signature to the forwarded HTTP request (Optional).
+        /// </summary>
+        public AbstractSignature Signature { get; set; }
     }
 }

src/CheckoutSdk/Forward/Requests/Signatures/AbstractSignature.cs

@@ -0,0 +1,13 @@
+namespace Checkout.Forward.Requests.Signatures
+{
+    public abstract class AbstractSignature
+    {
+        protected AbstractSignature(SignatureType type) { Type = type; }
+
+        /// <summary>
+        ///     The identifier of the supported signature generation method or a specific third-party service.
+        ///     (Required)
+        /// </summary>
+        public SignatureType? Type { get; set; }
+    }
+}

src/CheckoutSdk/Forward/Requests/Signatures/DlocalParameters.cs

@@ -0,0 +1,10 @@
+namespace Checkout.Forward.Requests.Signatures
+{
+    public class DlocalParameters
+    {
+        /// <summary>
+        ///     The secret key used to generate the request signature. This is part of the dLocal API credentials.
+        /// </summary>
+        public string SecretKey { get; set; }
+    }
+}

src/CheckoutSdk/Forward/Requests/Signatures/DlocalSignature.cs

@@ -0,0 +1,14 @@
+namespace Checkout.Forward.Requests.Signatures
+{
+    public class DlocalSignature
+    {
+        /// <summary>
+        ///     The parameters required to generate an HMAC signature for the dLocal API. See their documentation for
+        ///     details.
+        ///     This method requires you to provide the X-Login header value in the destination request headers.
+        ///     When used, the Forward API appends the X-Date and Authorization headers to the outgoing HTTP request
+        ///     before forwarding.
+        /// </summary>
+        public DlocalParameters DlocalParameters { get; set; }
+    }
+}

src/CheckoutSdk/Forward/Requests/Signatures/SignatureType.cs

@@ -0,0 +1,10 @@
+using System.Runtime.Serialization;
+
+namespace Checkout.Forward.Requests.Signatures
+{
+    public enum SignatureType
+    {
+        [EnumMember(Value = "dlocal")]
+        Dlocal,
+    }
+}