WebAPI ServiceStack

formatter.cs

using System;
using System.IO;
using System.Net;
using System.Net.Http;
using System.Net.Http.Formatting;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;
using EnsureThat;
using iLogMyDay.Core.Serialization;

namespace iLogMyDay.WebApp.Core
{
    public class ServiceStackFormatter : MediaTypeFormatter
    {
        protected readonly ISerializer Serializer;

        public ServiceStackFormatter(ISerializer serializer)
        {
            Ensure.That(serializer, "serializer").IsNotNull();
            Serializer = serializer;

            SupportedMediaTypes.Add(new MediaTypeWithQualityHeaderValue("application/json"));
            SupportedMediaTypes.Add(new MediaTypeWithQualityHeaderValue("text/json"));

            SupportedEncodings.Add(new UTF8Encoding(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true));
            SupportedEncodings.Add(new UnicodeEncoding(bigEndian: false, byteOrderMark: true, throwOnInvalidBytes: true));
        }

        public override bool CanReadType(Type type)
        {
            return true;
        }

        public override bool CanWriteType(Type type)
        {
            return true;
        }

        public override Task<object> ReadFromStreamAsync(Type type, Stream readStream, HttpContent content, IFormatterLogger formatterLogger)
        {
            return Task<object>.Factory.StartNew(() => Serializer.Deserialize(type, readStream));
        }

        public override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content, TransportContext transportContext)
        {
            return Task.Factory.StartNew(() => Serializer.Serialize(type, value, writeStream));
        }
    }
}

gistfile1.cs

private static void SetCustomJsonFormatter(HttpConfiguration apiConfig)
{
    var jsonFormatter = new ServiceStackFormatter(WebAppRuntime.Instance.ObjectResolver.Resolve<ISerializer>());
    var foundFormatterIndex = false;
    for (var i = 0; i < apiConfig.Formatters.Count; i++)
    {
        var f = apiConfig.Formatters[i];
        if (f.SupportedMediaTypes.Any(m => m.MediaType.Contains("json")))
        {
            foundFormatterIndex = true;
            apiConfig.Formatters[i] = jsonFormatter;
            break;
        }
    }

    if (!foundFormatterIndex)
        apiConfig.Formatters.Insert(0, jsonFormatter);
}