Fixes for Downloading ReleaseAsset zip File octokit#854

This commit  addressed the `BuildResponse`  wasn't handling
response `content-type` `application/octet-stream` for binary items.

Octokit.Tests.Integration/Clients/ReleasesClientTests.cs

@@ -1,6 +1,9 @@
 using System;
 using System.Collections.Generic;
+using System.IO;
+using System.IO.Compression;
 using System.Linq;
+using System.Text;
 using System.Threading.Tasks;
 using Octokit;
 using Octokit.Tests.Integration;
@@ -188,8 +191,45 @@ public async Task CanDownloadAnAsset()
 
             var response = await _github.Connection.Get<object>(new Uri(asset.Url), new Dictionary<string, string>(), "application/octet-stream");
 
-            Assert.Equal("This is a plain text file.", response.Body);
+            Assert.Contains("This is a plain text file.", Encoding.ASCII.GetString((byte[]) response.Body));
         }
+        [IntegrationTest]
+        public async Task CanDownloadBinaryAsset()
+        {
+            var releaseWithNoUpdate = new NewRelease("0.1") { Draft = true };
+            var release = await _releaseClient.Create(_context.RepositoryOwner, _context.RepositoryName, releaseWithNoUpdate);
+
+            var stream = Helper.LoadFixture("hello-world.zip");
+
+            var newAsset = new ReleaseAssetUpload("hello-world.zip"
+                , "application/octet-stream"
+                , stream
+                , null);
+
+            var result = await _releaseClient.UploadAsset(release, newAsset);
+
+            Assert.True(result.Id > 0);
+
+            var asset = await _releaseClient.GetAsset(_context.RepositoryOwner, _context.RepositoryName, result.Id);
+
+            Assert.Equal(result.Id, asset.Id);
+
+            var response = await _github.Connection.Get<object>(new Uri(asset.Url), new Dictionary<string, string>(), "application/octet-stream");
+
+            var textContent = String.Empty;
+
+            using (var zipstream = new MemoryStream((byte[]) response.Body))
+            using(var archive = new ZipArchive(zipstream))
+            {
+                var enttry = archive.Entries[0];
+                var data = new byte[enttry.Length];
+                await enttry.Open().ReadAsync(data, 0, data.Length);
+                textContent = Encoding.ASCII.GetString(data);
+            }
+
+            Assert.Contains("This is a plain text file.",textContent );
+        }
+
 
         public void Dispose()
         {

Octokit.Tests.Integration/Octokit.Tests.Integration.csproj

@@ -38,6 +38,8 @@
   <ItemGroup>
     <Reference Include="System" />
     <Reference Include="System.Core" />
+    <Reference Include="System.IO.Compression" />
+    <Reference Include="System.IO.Compression.FileSystem" />
     <Reference Include="System.Net.Http" />
     <Reference Include="System.Reactive.Core, Version=2.2.5.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
       <SpecificVersion>False</SpecificVersion>
@@ -144,6 +146,7 @@
   </ItemGroup>
   <ItemGroup>
     <None Include="app.config" />
+    <EmbeddedResource Include="fixtures\hello-world.zip" />
     <None Include="packages.config">
       <SubType>Designer</SubType>
     </None>

Octokit/Http/HttpClientAdapter.cs

@@ -70,16 +70,22 @@ protected async virtual Task<IResponse> BuildResponse(HttpResponseMessage respon
 
             object responseBody = null;
             string contentType = null;
+
+            // We added support for downloading images,zip-files and application/octet-stream. 
+            // Let's constrain this appropriately.
+            var binaryContentTypes = new[] {"application/zip"
+                ,"application/x-gzip",
+                "application/octet-stream"};
+
             using (var content = responseMessage.Content)
             {
                 if (content != null)
                 {
                     contentType = GetContentMediaType(responseMessage.Content);
 
-                    // We added support for downloading images and zip-files. Let's constrain this appropriately.
-                    if (contentType != null && (contentType.StartsWith("image/")
-                        || contentType.Equals("application/zip", StringComparison.OrdinalIgnoreCase)
-                        || contentType.Equals("application/x-gzip", StringComparison.OrdinalIgnoreCase)))
+                    if (contentType != null && (contentType.StartsWith("image/") ||
+                        binaryContentTypes
+                        .Any(item => item.Equals(contentType,StringComparison.OrdinalIgnoreCase))))
                     {
                         responseBody = await responseMessage.Content.ReadAsByteArrayAsync().ConfigureAwait(false);
                     }