Added a signer class for System.Net.Http.HttpClient

Author: jaaufauvre

Mastercard.Developer.OAuth1Signer.Core/Signers/NetHttpClientSigner.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Net.Http;
+using System.Net.Http.Headers;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace Mastercard.Developer.OAuth1Signer.Core.Signers
+{
+    /// <summary>
+    /// Utility class for signing System.Net.Http.HttpClient request objects.
+    /// </summary>
+    public class NetHttpClientSigner : BaseSigner
+    {
+        public NetHttpClientSigner(string consumerKey, RSA signingKey) : base(consumerKey, signingKey)
+        {
+        }
+
+        public NetHttpClientSigner(string consumerKey, RSA signingKey, Encoding encoding) : base(consumerKey, signingKey, encoding)
+        {
+        }
+
+        public void Sign(HttpRequestMessage request)
+        {
+            if (request == null) throw new ArgumentNullException(nameof(request));
+
+            string payload = null;
+            var httpContent = request.Content;
+            if (httpContent != null)
+            {
+                // Read the body
+                var bodyTask = httpContent.ReadAsStringAsync();
+                bodyTask.Wait();
+                payload = bodyTask.Result;
+            }
+
+            // Generate the header and add it to the request
+            var methodString = request.Method.ToString();
+            var header = OAuth.GetAuthorizationHeader(request.RequestUri.AbsoluteUri, methodString, payload, Encoding, ConsumerKey, SigningKey);
+            request.Headers.Authorization = new AuthenticationHeaderValue("OAuth", header.Replace("OAuth", string.Empty));
+        }
+    }
+}

Mastercard.Developer.OAuth1Signer.Tests/Signers/NetHttpClientSignerTest.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Net.Http;
+using Mastercard.Developer.OAuth1Signer.Core.Signers;
+using Mastercard.Developer.OAuth1Signer.Tests.Test;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace Mastercard.Developer.OAuth1Signer.Tests.Signers
+{
+    [TestClass]
+    public class NetHttpClientSignerTest
+    {
+        [TestMethod]
+        public void TestSign_ShouldAddOAuth1HeaderToRequest()
+        {
+            // GIVEN
+            var signingKey = TestUtils.GetTestPrivateKey();
+            const string consumerKey = "Some key";
+            var request = new HttpRequestMessage
+            {
+                Method = HttpMethod.Post,
+                RequestUri = new Uri("https://api.mastercard.com/service"),
+                Content = new StringContent("{\"foo\":\"bår\"}") // "application/json; charset=utf-8"
+            };
+
+            // WHEN
+            var instanceUnderTest = new NetHttpClientSigner(consumerKey, signingKey);
+            instanceUnderTest.Sign(request);
+
+            // THEN
+            Assert.IsNotNull(request.Headers.Authorization);
+        }
+    }
+}

README.md

@@ -83,11 +83,41 @@ These classes will modify the provided request object in-place and will add the
 
 Usage briefly described below, but you can also refer to the test project for examples. 
 
++ [System.Net.Http.HttpClient](#system-net-http-httpclient)
 + [RestSharp Portable](#restsharp-portable)
 
+#### System.Net.Http.HttpClient <a name="system-net-http-httpclient"></a>
+
+The `NetHttpClientSigner` class is located in the `Mastercard.Developer.OAuth1Signer.Core` package. 
+
+Usage:
+```cs
+var baseUri = new Uri("https://api.mastercard.com/");
+var httpClient = new HttpClient(new RequestSignerHandler(ConsumerKey, signingKey)) { BaseAddress = baseUri };
+var postTask = httpClient.PostAsync(new Uri("/service", UriKind.Relative), new StringContent("{\"foo\":\"bår\"}");
+
+// (...)
+
+internal class RequestSignerHandler : HttpClientHandler
+{
+    private readonly NetHttpClientSigner signer;
+
+    public RequestSignerHandler(string consumerKey, RSA signingKey)
+    {
+        signer = new NetHttpClientSigner(consumerKey, signingKey);
+    }
+
+    protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+    {
+        signer.Sign(request);
+        return base.SendAsync(request, cancellationToken);
+    }
+}
+```
+
 #### RestSharp Portable <a name="restsharp-portable"></a>
 
-The `RestSharpSigner` class is provided by the `Mastercard.Developer.OAuth1Signer.RestSharp` package. 
+The `RestSharpSigner` class is located in the `Mastercard.Developer.OAuth1Signer.RestSharp` package. 
 
 Usage:
 ```cs
@@ -128,7 +158,7 @@ config.json:
 
 ##### Usage of the RestSharpOAuth1Authenticator
 
-`RestSharpOAuth1Authenticator` is provided in the `Mastercard.Developer.OAuth1Signer.RestSharp` package. 
+`RestSharpOAuth1Authenticator` is located in the `Mastercard.Developer.OAuth1Signer.RestSharp` package. 
 
 ```cs
 var config = Configuration.Default;