Replace all other uses of hardcoded HTTP header strings to declare/use entries in the AcceptHeaders helper class

Left test methods alone as it isn't good practice to share these definitions between Test and Implementation classes

Octokit/Clients/MiscellaneousClient.cs

@@ -109,10 +109,9 @@ namespace Octokit
         /// <returns>A list of licenses available on the site</returns>
         public async Task<IReadOnlyList<LicenseMetadata>> GetAllLicenses()
         {
-            const string previewAcceptsHeader = "application/vnd.github.drax-preview+json";
             var endpoint = new Uri("licenses", UriKind.Relative);
 
-            var response = await _connection.Get<LicenseMetadata[]>(endpoint, null, previewAcceptsHeader)
+            var response = await _connection.Get<LicenseMetadata[]>(endpoint, null, AcceptHeaders.LicensesApiPreview)
                 .ConfigureAwait(false);
             return new ReadOnlyCollection<LicenseMetadata>(response.Body);
         }
@@ -124,10 +123,9 @@ namespace Octokit
         /// <returns>A <see cref="License" /> that includes the license key, text, and attributes of the license.</returns>
         public async Task<License> GetLicense(string key)
         {
-            const string previewAcceptsHeader = "application/vnd.github.drax-preview+json";
             var endpoint = new Uri("licenses/" + Uri.EscapeUriString(key), UriKind.Relative);
 
-            var response = await _connection.Get<License>(endpoint, null, previewAcceptsHeader)
+            var response = await _connection.Get<License>(endpoint, null, AcceptHeaders.LicensesApiPreview)
                 .ConfigureAwait(false);
             return response.Body;
         }

Octokit/Clients/ReleasesClient.cs

@@ -37,7 +37,7 @@ namespace Octokit
             Ensure.ArgumentNotNullOrEmptyString(name, "repository");
 
             var endpoint = ApiUrls.Releases(owner, name);
-            return ApiConnection.GetAll<Release>(endpoint, null, "application/vnd.github.v3");
+            return ApiConnection.GetAll<Release>(endpoint, null, AcceptHeaders.ReleaseApi);
         }
 
         /// <summary>
@@ -78,7 +78,7 @@ namespace Octokit
             Ensure.ArgumentNotNull(data, "data");
 
             var endpoint = ApiUrls.Releases(owner, name);
-            return ApiConnection.Post<Release>(endpoint, data, "application/vnd.github.v3");
+            return ApiConnection.Post<Release>(endpoint, data, AcceptHeaders.ReleaseApi);
         }
 
         /// <summary>
@@ -140,7 +140,7 @@ namespace Octokit
             Ensure.ArgumentNotNullOrEmptyString(name, "name");
 
             var endpoint = ApiUrls.ReleaseAssets(owner, name, id);
-            return ApiConnection.GetAll<ReleaseAsset>(endpoint, null, "application/vnd.github.v3");
+            return ApiConnection.GetAll<ReleaseAsset>(endpoint, null, AcceptHeaders.ReleaseApi);
         }
 
         /// <summary>
@@ -165,7 +165,7 @@ namespace Octokit
                 return ApiConnection.Post<ReleaseAsset>(
                     endpoint,
                     data.RawData,
-                    "application/vnd.github.v3",
+                    AcceptHeaders.ReleaseApi,
                     data.ContentType,
                     data.Timeout.GetValueOrDefault());
             }
@@ -173,7 +173,7 @@ namespace Octokit
             return ApiConnection.Post<ReleaseAsset>(
                 endpoint,
                 data.RawData,
-                "application/vnd.github.v3",
+                AcceptHeaders.ReleaseApi,
                 data.ContentType);
         }
 

Octokit/Helpers/AcceptHeaders.cs

@@ -2,6 +2,14 @@
 {
     public static class AcceptHeaders
     {
+        public const string DefaultJson = "application/vnd.github.quicksilver-preview+json; charset=utf-8, application/vnd.github.v3+json; charset=utf-8";
+
+        public const string DefaultHtml = "application/vnd.github.html";
+
+        public const string ReleaseApi = "application/vnd.github.v3";
+
+        public const string LicensesApiPreview = "application/vnd.github.drax-preview+json";
+
         public const string ProtectedBranchesApiPreview = "application/vnd.github.loki-preview+json";
     }
 }

Octokit/Http/Connection.cs

@@ -519,7 +519,7 @@ namespace Octokit
 
         async Task<IApiResponse<string>> GetHtml(IRequest request)
         {
-            request.Headers.Add("Accept", "application/vnd.github.html");
+            request.Headers.Add("Accept", AcceptHeaders.DefaultHtml);
             var response = await RunRequest(request, CancellationToken.None);
             return new ApiResponse<string>(response, response.Body as string);
         }

Octokit/Http/JsonHttpPipeline.cs

@@ -11,7 +11,7 @@ namespace Octokit.Internal
     /// </summary>
     public class JsonHttpPipeline
     {
-        private const string v3ApiVersion = "application/vnd.github.quicksilver-preview+json; charset=utf-8, application/vnd.github.v3+json; charset=utf-8";
+        private const string v3ApiVersion = AcceptHeaders.DefaultJson;
 
         readonly IJsonSerializer _serializer;