/src/MassTransit/Serialization/StringMessageSerializer.cs

// Copyright 2007-2016 Chris Patterson, Dru Sellers, Travis Smith, et. al.

//  

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use

// this file except in compliance with the License. You may obtain a copy of the 

// License at 

// 

//     http://www.apache.org/licenses/LICENSE-2.0 

// 

// Unless required by applicable law or agreed to in writing, software distributed

// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR 

// CONDITIONS OF ANY KIND, either express or implied. See the License for the 

// specific language governing permissions and limitations under the License.

namespace MassTransit.Serialization

{

    using System.Collections.Generic;

    using System.IO;

    using System.Linq;

    using System.Net.Mime;

    using System.Text;

    using System.Xml.Linq;

    using Newtonsoft.Json;

    using Newtonsoft.Json.Linq;





    /// <summary>

    /// A body serializer takes a byte array message body and just streams it out to the message

    /// unmodified.

    /// </summary>

    public class StringMessageSerializer :

        IMessageSerializer

    {

        readonly Encoding _encoding;

        string _body;



        public StringMessageSerializer(ContentType contentType, string body, Encoding encoding = null)

        {

            ContentType = contentType;

            _body = body;

            _encoding = encoding ?? Encoding.UTF8;

        }



        public ContentType ContentType { get; }



        public void Serialize<T>(Stream stream, SendContext<T> context)

            where T : class

        {

            byte[] body = _encoding.GetBytes(_body);



            stream.Write(body, 0, body.Length);

        }



        public void UpdateJsonHeaders(IDictionary<string, object> values)

        {

            var envelope = JObject.Parse(_body);



            var headersToken = envelope["headers"] ?? new JObject();

            var headers = headersToken.ToObject<Dictionary<string, object>>();



            foreach (KeyValuePair<string, object> payloadHeader in values)

            {

                headers[payloadHeader.Key] = payloadHeader.Value;

            }



            envelope["headers"] = JToken.FromObject(headers);



            _body = JsonConvert.SerializeObject(envelope, Formatting.Indented);

        }



        public void UpdateXmlHeaders(IDictionary<string, object> values)

        {

            using (var reader = new StringReader(_body))

            {

                var document = XDocument.Load(reader);



                var envelope = (from e in document.Descendants("envelope") select e).Single();



                var headers = (from h in envelope.Descendants("headers") select h).SingleOrDefault();

                if (headers == null)

                {

                    headers = new XElement("headers");

                    envelope.Add(headers);

                }



                foreach (KeyValuePair<string, object> payloadHeader in values)

                {

                    headers.Add(new XElement(payloadHeader.Key, payloadHeader.Value));

                }



                _body = document.ToString(SaveOptions.DisableFormatting);

            }

        }

    }

}