/WCFWebApi/src/Microsoft.ApplicationServer.Http/Microsoft/ApplicationServer/Http/Dispatcher/HttpMessageFormatter.cs

// <copyright>

//   Copyright (c) Microsoft Corporation.  All rights reserved.

// </copyright>



namespace Microsoft.ApplicationServer.Http.Dispatcher

{

    using System;

    using System.Net.Http;

    using System.ServiceModel.Channels;

    using System.ServiceModel.Dispatcher;

    using Microsoft.ApplicationServer.Http.Channels;

    using Microsoft.Server.Common;



    /// <summary>

    /// Abstract base class that defines methods to deserialize request messages

    /// and serialize response messages for the

    /// <see cref="HttpBinding">HttpBinding</see>.

    /// </summary>

    public abstract class HttpMessageFormatter : IDispatchMessageFormatter

    {

        /// <summary>

        /// Deserializes a message into an array of parameters.

        /// </summary>

        /// <param name="message">The incoming message.</param>

        /// <param name="parameters">The objects that are passed to the operation as parameters.</param>

        void IDispatchMessageFormatter.DeserializeRequest(Message message, object[] parameters)

        {

            if (message == null)

            {

                throw Fx.Exception.ArgumentNull("message");

            }



            HttpRequestMessage request = message.ToHttpRequestMessage();

            if (request == null)

            {

                throw Fx.Exception.AsError(

                    new InvalidOperationException(

                        Http.SR.HttpMessageFormatterNullMessage(this.GetType().Name, typeof(HttpRequestMessage).Name, "DeserializeRequest")));

            }



            this.DeserializeRequest(request, parameters);

        }



        /// <summary>

        /// Serializes a reply message from a specified message version, array of parameters, and a return value.

        /// </summary>

        /// <param name="messageVersion">The SOAP message version.</param>

        /// <param name="parameters">The out parameters.</param>

        /// <param name="result">The return value.</param>

        /// <returns>The serialized reply message.</returns>

        Message IDispatchMessageFormatter.SerializeReply(

                                              MessageVersion messageVersion, 

                                              object[] parameters, 

                                              object result)

        {

            if (messageVersion != MessageVersion.None)

            {

                throw Fx.Exception.AsError(

                    new NotSupportedException(

                        Http.SR.HttpMessageFormatterMessageVersion(this.GetType(), typeof(MessageVersion), "None")));

            }



            HttpResponseMessage response = this.SerializeReply(parameters, result);

            Fx.Assert(response != null, "Response cannot be null.");

            return response.ToMessage();

        }



        /// <summary>

        /// Deserializes a message into an array of parameters.

        /// </summary>

        /// <param name="request">The incoming message.</param>

        /// <param name="parameters">The objects that are passed to the operation as parameters.</param>

        public void DeserializeRequest(HttpRequestMessage request, object[] parameters)

        {

            if (request == null)

            {

                throw Fx.Exception.ArgumentNull("request");

            }



            if (parameters == null)

            {

                throw Fx.Exception.ArgumentNull("parameters");

            }



            this.OnDeserializeRequest(request, parameters);

        }



        /// <summary>

        /// Serializes a reply message from an array of parameters and a return value into the

        /// given <paramref name="result"/>.

        /// </summary>

        /// <param name="parameters">The out parameters.</param>

        /// <param name="result">The return value.</param>

        /// <returns>The <see cref="HttpResponseMessage"/> to return.  It cannot be <c>null</c>.</returns>

        public HttpResponseMessage SerializeReply(object[] parameters, object result)

        {

            if (parameters == null)

            {

                throw Fx.Exception.ArgumentNull("parameters");

            }



            HttpResponseMessage responseMessage = this.OnSerializeReply(parameters, result);

            if (responseMessage == null)

            {

                throw Fx.Exception.AsError(

                    new InvalidOperationException(

                        Http.SR.HttpMessageFormatterNullMessage(this.GetType(), typeof(HttpResponseMessage).Name, "SerializeReply")));

            }



            return responseMessage;

        }



        /// <summary>

        /// Deserializes a message into an array of parameters.

        /// </summary>

        /// <param name="message">The incoming message.</param>

        /// <param name="parameters">The objects that are passed to the operation as parameters.</param>

        protected abstract void OnDeserializeRequest(HttpRequestMessage message, object[] parameters);



        /// <summary>

        /// Serializes a reply message from an array of parameters and a return value into the

        /// given <paramref name="result"/>.

        /// </summary>

        /// <param name="parameters">The out parameters.</param>

        /// <param name="result">The return value.</param>

        /// <returns>The <see cref="HttpResponseMessage"/> to return.  It cannot be <c>null</c>.</returns>

        protected abstract HttpResponseMessage OnSerializeReply(object[] parameters, object result);

    }

}