ResponseBodyWriter.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DataWeb / Server / System / Data / Services / ResponseBodyWriter.cs / 1305376 / ResponseBodyWriter.cs

                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//  
//      Provides a base class for DataWeb services.
//  
// 
// @owner  [....]
//--------------------------------------------------------------------- 

namespace System.Data.Services
{
    using System; 
    using System.Collections;
    using System.Data.Services.Providers; 
    using System.Data.Services.Serializers; 
    using System.Diagnostics;
    using System.IO; 
    using System.Text;

    /// 
    /// Use this class to encapsulate writing the body of the outgoing response 
    /// for a data request.
    ///  
    internal class ResponseBodyWriter 
    {
        /// Encoding, if available. 
        private readonly Encoding encoding;

        /// Whether  has already moved.
        private readonly bool hasMoved; 

        /// Host for the request being processed. 
        private readonly IDataService service; 

        /// Enumerator for results. 
        private readonly IEnumerator queryResults;

        /// Description of request made to the system.
        private readonly RequestDescription requestDescription; 

        /// Content format for response. 
        private readonly ContentFormat responseFormat; 

        /// If the target is a Media Resource, this holds the read stream for the Media Resource. 
        private Stream mediaResourceStream;

        /// Initializes a new  that can write the body of a response.
        /// Encoding, if available. 
        /// Whether  has already moved.
        /// Service for the request being processed. 
        /// Enumerator for results. 
        /// Description of request made to the system.
        /// Content format for response. 
        internal ResponseBodyWriter(
            Encoding encoding,
            bool hasMoved,
            IDataService service, 
            IEnumerator queryResults,
            RequestDescription requestDescription, 
            ContentFormat responseFormat) 
        {
            Debug.Assert(responseFormat != ContentFormat.Unknown, "responseFormat != ContentFormat.Unknown"); 
            this.encoding = encoding;
            this.hasMoved = hasMoved;
            this.service = service;
            this.queryResults = queryResults; 
            this.requestDescription = requestDescription;
            this.responseFormat = responseFormat; 
 
            if (this.requestDescription.TargetKind == RequestTargetKind.MediaResource)
            { 
                // Note that GetReadStream will set the ResponseETag before it returns
                this.mediaResourceStream = service.StreamProvider.GetReadStream(this.queryResults.Current, this.service.OperationContext);
            }
        } 

        /// Gets the absolute URI to the service. 
        internal Uri AbsoluteServiceUri 
        {
            get { return this.service.OperationContext.AbsoluteServiceUri; } 
        }

        /// Gets the  for this response.
        internal DataServiceHostWrapper Host 
        {
            get { return this.service.OperationContext.Host; } 
        } 

        /// Gets the  for this response. 
        internal DataServiceProviderWrapper Provider
        {
            get { return this.service.Provider; }
        } 

        /// Writes the request body to the specified . 
        /// Stream to write to. 
        internal void Write(Stream stream)
        { 
            Debug.Assert(stream != null, "stream != null");
            IExceptionWriter exceptionWriter = null;

            try 
            {
                switch (this.responseFormat) 
                { 
                    case ContentFormat.Binary:
                        Debug.Assert( 
                            this.requestDescription.TargetKind == RequestTargetKind.OpenPropertyValue ||
                            this.requestDescription.TargetKind == RequestTargetKind.PrimitiveValue ||
                            this.requestDescription.TargetKind == RequestTargetKind.MediaResource,
                            this.requestDescription.TargetKind + " is PrimitiveValue or OpenPropertyValue or StreamPropertyValue"); 

                        BinarySerializer binarySerializer = new BinarySerializer(stream); 
                        exceptionWriter = binarySerializer; 
                        if (this.requestDescription.TargetKind == RequestTargetKind.MediaResource)
                        { 
                            Debug.Assert(this.mediaResourceStream != null, "this.mediaResourceStream != null");

                            binarySerializer.WriteRequest(this.mediaResourceStream, this.service.StreamProvider.StreamBufferSize);
                        } 
                        else
                        { 
                            binarySerializer.WriteRequest(this.queryResults.Current); 
                        }
 
                        break;

                    case ContentFormat.Text:
                        Debug.Assert( 
                            this.requestDescription.TargetKind == RequestTargetKind.OpenPropertyValue ||
                            this.requestDescription.TargetKind == RequestTargetKind.PrimitiveValue, 
                            this.requestDescription.TargetKind + " is PrimitiveValue or OpenPropertyValue"); 

                        TextSerializer textSerializer = new TextSerializer(stream, this.encoding); 
                        exceptionWriter = textSerializer;
                        textSerializer.WriteRequest(this.queryResults.Current);
                        break;
 
                    case ContentFormat.Atom:
                    case ContentFormat.Json: 
                    case ContentFormat.PlainXml: 
                        Debug.Assert(this.requestDescription.TargetKind != RequestTargetKind.PrimitiveValue, "this.requestDescription.TargetKind != RequestTargetKind.PrimitiveValue");
                        Debug.Assert(this.requestDescription.TargetKind != RequestTargetKind.OpenPropertyValue, "this.requestDescription.TargetKind != RequestTargetKind.OpenPropertyValue"); 
                        Debug.Assert(this.requestDescription.TargetKind != RequestTargetKind.Metadata, "this.requestDescription.TargetKind != RequestTargetKind.Metadata");

                        if (this.requestDescription.TargetKind == RequestTargetKind.ServiceDirectory)
                        { 
                            if (this.responseFormat == ContentFormat.Json)
                            { 
                                JsonServiceDocumentSerializer serviceSerializer = new JsonServiceDocumentSerializer(stream, this.Provider, this.encoding); 
                                exceptionWriter = serviceSerializer;
                                serviceSerializer.WriteRequest(); 
                                break;
                            }
                            else
                            { 
                                AtomServiceDocumentSerializer serviceSerializer = new AtomServiceDocumentSerializer(stream, this.AbsoluteServiceUri, this.Provider, this.encoding);
                                exceptionWriter = serviceSerializer; 
                                serviceSerializer.WriteRequest(this.service); 
                            }
                        } 
                        else
                        {
                            Serializer serializer;
                            if (ContentFormat.Json == this.responseFormat) 
                            {
                                serializer = new JsonSerializer(this.requestDescription, stream, this.AbsoluteServiceUri, this.service, this.encoding, this.Host.ResponseETag); 
                            } 
                            else if (ContentFormat.PlainXml == this.responseFormat)
                            { 
                                serializer = new PlainXmlSerializer(this.requestDescription, this.AbsoluteServiceUri, this.service, stream, this.encoding);
                            }
                            else
                            { 
                                Debug.Assert(
                                    this.requestDescription.TargetKind == RequestTargetKind.OpenProperty || 
                                    this.requestDescription.TargetKind == RequestTargetKind.Resource, 
                                    "TargetKind " + this.requestDescription.TargetKind + " == Resource || OpenProperty -- POX should have handled it otherwise.");
                                serializer = new SyndicationSerializer( 
                                    this.requestDescription,
                                    this.AbsoluteServiceUri,
                                    this.service,
                                    stream, 
                                    this.encoding,
                                    this.Host.ResponseETag, 
                                    new Atom10FormatterFactory()); 
                            }
 
                            exceptionWriter = serializer;
                            Debug.Assert(exceptionWriter != null, "this.exceptionWriter != null");
                            serializer.WriteRequest(this.queryResults, this.hasMoved);
                        } 

                        break; 
 
                    default:
                        Debug.Assert( 
                            this.responseFormat == ContentFormat.MetadataDocument,
                            "responseFormat(" + this.responseFormat + ") == ContentFormat.MetadataDocument -- otherwise exception should have been thrown before");
                        Debug.Assert(this.requestDescription.TargetKind == RequestTargetKind.Metadata, "this.requestDescription.TargetKind == RequestTargetKind.Metadata");
                        MetadataSerializer metadataSerializer = new MetadataSerializer(stream, this.AbsoluteServiceUri, this.Provider, this.encoding); 
                        exceptionWriter = metadataSerializer;
                        metadataSerializer.WriteRequest(this.service); 
                        break; 
                }
            } 
            catch (Exception exception)
            {
                if (!WebUtil.IsCatchableExceptionType(exception))
                { 
                    throw;
                } 
 
                // Only JSON and XML are supported.
                string contentType = (this.responseFormat == ContentFormat.Json) ? XmlConstants.MimeApplicationJson : XmlConstants.MimeApplicationXml; 
                ErrorHandler.HandleDuringWritingException(exception, this.service, contentType, exceptionWriter);
            }
            finally
            { 
                WebUtil.Dispose(this.queryResults);
                WebUtil.Dispose(this.mediaResourceStream); 
            } 
        }
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.


                        

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