fix AllowSynchronousIO required

Author: damienbod

src/WebApiContrib.Core.Formatter.Protobuf/ProtobufInputFormatter.cs

@@ -1,4 +1,5 @@
 using System;
+using System.IO;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc.Formatters;
 using Microsoft.Net.Http.Headers;
@@ -31,15 +32,19 @@ public static RuntimeTypeModel Model
             get { return model.Value; }
         }
 
-        public override Task<InputFormatterResult> ReadRequestBodyAsync(InputFormatterContext context)
+        public override async Task<InputFormatterResult> ReadRequestBodyAsync(InputFormatterContext context)
         {
             var type = context.ModelType;
             var request = context.HttpContext.Request;
             MediaTypeHeaderValue requestContentType = null;
             MediaTypeHeaderValue.TryParse(request.ContentType, out requestContentType);
 
-            object result = Model.Deserialize(context.HttpContext.Request.Body, null, type);
-            return InputFormatterResult.SuccessAsync(result);
+            MemoryStream stream = new MemoryStream();
+            await request.Body.CopyToAsync(stream);
+
+            stream.Position = 0;
+            object result = Model.Deserialize(stream, null, type);
+            return await InputFormatterResult.SuccessAsync(result);
         }
 
         protected override bool CanReadType(Type type)

src/WebApiContrib.Core.Formatter.Protobuf/ProtobufOutputFormatter.cs

@@ -1,5 +1,7 @@
 using System;
+using System.IO;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Formatters;
 using Microsoft.Net.Http.Headers;
 using ProtoBuf.Meta;
@@ -9,15 +11,15 @@ namespace WebApiContrib.Core.Formatter.Protobuf
     public class ProtobufOutputFormatter :  OutputFormatter
     {
         private readonly ProtobufFormatterOptions _options;
-
-        public ProtobufOutputFormatter(ProtobufFormatterOptions protobufFormatterOptions)
-        {
-            ContentType = "application/x-protobuf";
-            _options = protobufFormatterOptions ?? throw new ArgumentNullException(nameof(protobufFormatterOptions));
-            foreach (var contentType in protobufFormatterOptions.SupportedContentTypes)
-            {
-                SupportedMediaTypes.Add(new MediaTypeHeaderValue(contentType));
-            }
+
+        public ProtobufOutputFormatter(ProtobufFormatterOptions protobufFormatterOptions)
+        {
+            ContentType = "application/x-protobuf";
+            _options = protobufFormatterOptions ?? throw new ArgumentNullException(nameof(protobufFormatterOptions));
+            foreach (var contentType in protobufFormatterOptions.SupportedContentTypes)
+            {
+                SupportedMediaTypes.Add(new MediaTypeHeaderValue(contentType));
+            }
         }
 
         private static Lazy<RuntimeTypeModel> model = new Lazy<RuntimeTypeModel>(CreateTypeModel);
@@ -36,12 +38,16 @@ private static RuntimeTypeModel CreateTypeModel()
             return typeModel;
         }
 
-        public override Task WriteResponseBodyAsync(OutputFormatterWriteContext context)
+        public override async Task WriteResponseBodyAsync(OutputFormatterWriteContext context)
         {
             var response = context.HttpContext.Response;
-    
-            Model.Serialize(response.Body, context.Object);
-            return Task.FromResult(response);
+
+            MemoryStream stream = new MemoryStream();
+            Model.Serialize(stream, context.Object);
+
+            stream.Position = 0;
+            var sr = new StreamReader(stream);
+            await response.WriteAsync(sr.ReadToEnd());
         }
     }
 }