Serialize directly into compression stream when making compressed result

src/ServiceStack.Client/Support/NetDeflateProvider.cs

@@ -34,6 +34,10 @@ public string Inflate(byte[] gzBuffer)
             }
         }
 
+        public Stream GetDeflateStream(Stream outputStream)
+        {
+            return new DeflateStream(outputStream, CompressionMode.Compress);
+        }
     }
 }
 #endif

src/ServiceStack.Client/Support/NetGZipProvider.cs

@@ -32,6 +32,11 @@ public string GUnzip(byte[] gzBuffer)
                 return Encoding.UTF8.GetString(utf8Bytes, 0, utf8Bytes.Length);
             }
         }
+
+        public Stream GetGZipCompressionStream(Stream outputStream)
+        {
+            return new GZipStream(outputStream, CompressionMode.Compress);
+        }
     }
 }
 #endif

src/ServiceStack.Interfaces/Caching/IDeflateProvider.cs

@@ -1,9 +1,13 @@
+using System.IO;
+
 namespace ServiceStack.Caching
 {
     public interface IDeflateProvider
     {
         byte[] Deflate(string text);
 
         string Inflate(byte[] gzBuffer);
+
+        Stream GetDeflateStream(Stream outputStream);
     }
 }

src/ServiceStack.Interfaces/Caching/IGZipProvider.cs

@@ -1,9 +1,13 @@
+using System.IO;
+
 namespace ServiceStack.Caching
 {
     public interface IGZipProvider
     {
         byte[] GZip(string text);
 
         string GUnzip(byte[] gzBuffer);
+
+        Stream GetGZipCompressionStream(Stream outputStream);
     }
 }

src/ServiceStack/RequestExtensions.cs

@@ -1,4 +1,5 @@
 using System;
+using System.IO;
 using ServiceStack.Caching;
 using ServiceStack.Host;
 using ServiceStack.Web;
@@ -49,16 +50,32 @@ public static object ToOptimizedResult<T>(this IRequest request, T dto)
         {
             request.Response.Dto = dto;
 
-            string serializedDto = HostContext.ContentTypes.SerializeToString(request, dto);
             var compressionType = request.GetCompressionType();
             if (compressionType == null)
-                return (object)serializedDto;
+                return (object)HostContext.ContentTypes.SerializeToString(request, dto);
 
-            byte[] compressedBytes = serializedDto.Compress(compressionType);
-            return new CompressedResult(compressedBytes, compressionType, request.ResponseContentType)
+            using (var ms = new MemoryStream())
+            using (var compressionStream = GetCompressionStream(ms, compressionType))
             {
-                Status = request.Response.StatusCode
-            };
+                HostContext.ContentTypes.SerializeToStream(request, dto, compressionStream);
+                compressionStream.Close();
+
+                var compressedBytes = ms.ToArray();
+                return new CompressedResult(compressedBytes, compressionType, request.ResponseContentType)
+                {
+                    Status = request.Response.StatusCode
+                };
+            }
+        }
+
+        private static Stream GetCompressionStream(Stream outputStream, string compressionType)
+        {
+            if (compressionType == CompressionTypes.Deflate)
+                return StreamExt.DeflateProvider.GetDeflateStream(outputStream);
+            if (compressionType == CompressionTypes.GZip)
+                return StreamExt.GZipProvider.GetGZipCompressionStream(outputStream);
+
+            throw new NotSupportedException(compressionType);
         }
 
         /// <summary>