use a stream rather than byte array in responder (#519)

src/Ocelot/Errors/Middleware/ExceptionHandlerMiddleware.cs

@@ -1,15 +1,14 @@
-using System;
-using System.Linq;
-using System.Threading.Tasks;
-using Ocelot.Configuration.Repository;
-using Ocelot.Infrastructure.Extensions;
-using Ocelot.Infrastructure.RequestData;
-using Ocelot.Logging;
-using Ocelot.Middleware;
-
 namespace Ocelot.Errors.Middleware
 {
     using Configuration;
+    using System;
+    using System.Linq;
+    using System.Threading.Tasks;
+    using Ocelot.Configuration.Repository;
+    using Ocelot.Infrastructure.Extensions;
+    using Ocelot.Infrastructure.RequestData;
+    using Ocelot.Logging;
+    using Ocelot.Middleware;
     
     /// <summary>
     /// Catches all unhandled exceptions thrown by middleware, logs and returns a 500

src/Ocelot/Responder/HttpContextResponder.cs

@@ -36,7 +36,7 @@ namespace Ocelot.Responder
                 AddHeaderIfDoesntExist(context, new Header(httpResponseHeader.Key, httpResponseHeader.Value));
             }
 
-            var content = await response.Content.ReadAsByteArrayAsync();
+            var content = await response.Content.ReadAsStreamAsync();
 
             AddHeaderIfDoesntExist(context, new Header("Content-Length", new []{ content.Length.ToString() }) );
 
@@ -49,11 +49,11 @@ namespace Ocelot.Responder
                 return Task.CompletedTask;
             }, context);
 
-            using (Stream stream = new MemoryStream(content))
+            using(content)
             {
                 if (response.StatusCode != HttpStatusCode.NotModified && context.Response.ContentLength != 0)
                 {
-                    await stream.CopyToAsync(context.Response.Body);
+                    await content.CopyToAsync(context.Response.Body);
                 }
             }
         }