示例#1
0
        /// <inheritdoc/>
        public override bool CanWriteType(Type type)
        {
            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }

            if (Request != null)
            {
                ODataSerializerProvider serializerProvider = Request.GetRequestContainer()
                                                             .GetRequiredService <ODataSerializerProvider>();

                // See if this type is a SingleResult or is derived from SingleResult.
                bool isSingleResult = false;
                if (type.IsGenericType)
                {
                    Type genericType = type.GetGenericTypeDefinition();
                    Type baseType    = TypeHelper.GetBaseType(type);
                    isSingleResult = (genericType == typeof(SingleResult <>) || baseType == typeof(SingleResult));
                }

                return(ODataOutputFormatterHelper.CanWriteType(
                           type,
                           _payloadKinds,
                           isSingleResult,
                           new WebApiRequestMessage(Request),
                           (objectType) => serializerProvider.GetODataPayloadSerializer(objectType, Request)));
            }

            return(false);
        }
        /// <inheritdoc/>
        public override bool CanWriteType(Type type)
        {
            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }

            ODataSerializer serializer = _serializerProvider.GetODataPayloadSerializer(type);

            if (serializer == null)
            {
                return(false);
            }

            return(_payloadKinds.Contains(serializer.ODataPayloadKind));
        }
示例#3
0
        /// <inheritdoc/>
        public override Task WriteResponseBodyAsync(OutputFormatterWriteContext context, Encoding selectedEncoding)
        {
            Type type = context.ObjectType;

            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }
            type = TypeHelper.GetTaskInnerTypeOrSelf(type);

            HttpRequest request = context.HttpContext.Request;

            if (request == null)
            {
                throw Error.InvalidOperation(SRResources.WriteToStreamAsyncMustHaveRequest);
            }

            HttpResponse response = context.HttpContext.Response;

            if (typeof(Stream).IsAssignableFrom(type))
            {
                // Ideally, it should go into the "ODataRawValueSerializer",
                // However, OData lib doesn't provide the method to overwrite/copyto stream
                // So, Here's the workaround
                Stream objStream = context.Object as Stream;
                return(CopyStreamAsync(objStream, response));
            }

            Uri baseAddress = GetBaseAddressInternal(request);
            MediaTypeHeaderValue contentType = GetContentType(response.Headers[HeaderNames.ContentType].FirstOrDefault());

            Func <ODataSerializerContext> getODataSerializerContext = () =>
            {
                return(new ODataSerializerContext()
                {
                    Request = request,
                });
            };

            ODataSerializerProvider serializerProvider = request.GetRequestContainer().GetRequiredService <ODataSerializerProvider>();

            return(ODataOutputFormatterHelper.WriteToStreamAsync(
                       type,
                       context.Object,
                       request.GetModel(),
                       ResultHelpers.GetODataResponseVersion(request),
                       baseAddress,
                       contentType,
                       new WebApiUrlHelper(request.GetUrlHelper()),
                       new WebApiRequestMessage(request),
                       new WebApiRequestHeaders(request.Headers),
                       (services) => ODataMessageWrapperHelper.Create(new StreamWrapper(response.Body), response.Headers, services),
                       (edmType) => serializerProvider.GetEdmTypeSerializer(edmType),
                       (objectType) => serializerProvider.GetODataPayloadSerializer(objectType, request),
                       getODataSerializerContext));
        }
示例#4
0
        public override Task WriteResponseBodyAsync(OutputFormatterWriteContext context, Encoding selectedEncoding)
        {
            Type type = context.ObjectType;

            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }
            type = TypeHelper.GetTaskInnerTypeOrSelf(type);

            HttpRequest request = context.HttpContext.Request;

            if (request == null)
            {
                throw Error.InvalidOperation(SRResources.WriteToStreamAsyncMustHaveRequest);
            }

            try
            {
                HttpResponse         response    = context.HttpContext.Response;
                Uri                  baseAddress = GetBaseAddressInternal(request);
                MediaTypeHeaderValue contentType = GetContentType(response.Headers[HeaderNames.ContentType].FirstOrDefault());

                Func <ODataSerializerContext> getODataSerializerContext = () =>
                {
                    return(new ODataSerializerContext()
                    {
                        Request = request,
                    });
                };

                ODataSerializerProvider serializerProvider = request.GetRequestContainer().GetRequiredService <ODataSerializerProvider>();

                ODataOutputFormatterHelper.WriteToStream(
                    type,
                    context.Object,
                    request.GetModel(),
                    ResultHelpers.GetODataResponseVersion(request),
                    baseAddress,
                    contentType,
                    new WebApiUrlHelper(request.GetUrlHelper()),
                    new WebApiRequestMessage(request),
                    new WebApiRequestHeaders(request.Headers),
                    (services) => ODataMessageWrapperHelper.Create(response.Body, response.Headers, services),
                    (edmType) => serializerProvider.GetEdmTypeSerializer(edmType),
                    (objectType) => serializerProvider.GetODataPayloadSerializer(objectType, request),
                    getODataSerializerContext);

                return(TaskHelpers.Completed());
            }
            catch (Exception ex)
            {
                return(TaskHelpers.FromError(ex));
            }
        }
        /// <inheritdoc/>
        public override bool CanWriteType(Type type)
        {
            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }

            ODataSerializer serializer = ODataSerializerProvider.GetODataPayloadSerializer(type);

            return(serializer != null);
        }
示例#6
0
        private ODataPayloadKind?GetClrObjectResponsePayloadKind(Type type, IEdmModel model)
        {
            // SingleResult<T> should be serialized as T.
            if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(SingleResult <>))
            {
                type = type.GetGenericArguments()[0];
            }

            ODataSerializer serializer = _serializerProvider.GetODataPayloadSerializer(model, type, Request);

            return(serializer == null ? null : (ODataPayloadKind?)serializer.ODataPayloadKind);
        }
        /// <inheritdoc/>
        public override bool CanWriteType(Type type)
        {
            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }

            if (_request != null)
            {
                IEdmModel model = _request.GetEdmModel();
                if (model != null)
                {
                    ODataSerializer serializer = _serializerProvider.GetODataPayloadSerializer(model, type);
                    if (serializer != null)
                    {
                        return(_payloadKinds.Contains(serializer.ODataPayloadKind));
                    }
                }
            }

            return(false);
        }
        private static ODataPayloadKind?GetClrObjectResponsePayloadKind(Type type, bool isGenericSingleResult,
                                                                        ODataSerializerProvider serializerProvider, HttpRequest request)
        {
            // SingleResult<T> should be serialized as T.
            if (isGenericSingleResult)
            {
                type = type.GetGenericArguments()[0];
            }

            ODataSerializer serializer = serializerProvider.GetODataPayloadSerializer(type, request);

            return(serializer == null ? null : (ODataPayloadKind?)serializer.ODataPayloadKind);
        }
        private ODataSerializer GetSerializer(Type type, object value, ODataSerializerProvider serializerProvider)
        {
            ODataSerializer serializer;

            IEdmObject edmObject = value as IEdmObject;

            if (edmObject != null)
            {
                IEdmStructuredObject edmStructuredObject = edmObject as IEdmStructuredObject;
                if (edmStructuredObject != null)
                {
                    edmStructuredObject.SetModel(Request.GetModel());
                }

                IEdmTypeReference edmType = edmObject.GetEdmType();
                if (edmType == null)
                {
                    throw new SerializationException(Error.Format(SRResources.EdmTypeCannotBeNull,
                                                                  edmObject.GetType().FullName, typeof(IEdmObject).Name));
                }

                serializer = serializerProvider.GetEdmTypeSerializer(edmType);
                if (serializer == null)
                {
                    string message = Error.Format(SRResources.TypeCannotBeSerialized, edmType.ToTraceString(), typeof(ODataMediaTypeFormatter).Name);
                    throw new SerializationException(message);
                }
            }
            else
            {
                var applyClause = Request.ODataProperties().ApplyClause;
                // get the most appropriate serializer given that we support inheritance.
                if (applyClause == null)
                {
                    type = value == null ? type : value.GetType();
                }

                serializer = serializerProvider.GetODataPayloadSerializer(type, Request);
                if (serializer == null)
                {
                    string message = Error.Format(SRResources.TypeCannotBeSerialized, type.Name, typeof(ODataMediaTypeFormatter).Name);
                    throw new SerializationException(message);
                }
            }

            return(serializer);
        }
        /// <summary>
        /// Gets the serializer for the given result type.
        /// The proxy provider will get the real provider to return the serializer.
        /// </summary>
        /// <param name="model">The EDM model.</param>
        /// <param name="type">The type of result to serialize.</param>
        /// <param name="request">The HTTP request.</param>
        /// <returns>The serializer instance.</returns>
        public override ODataSerializer GetODataPayloadSerializer(
            IEdmModel model,
            Type type,
            HttpRequestMessage request)
        {
            this.api = request.GetApiInstance();

            if (this.api != null)
            {
                ODataSerializerProvider provider = api.Context.GetApiService <ODataSerializerProvider>();
                if (provider != null)
                {
                    return(provider.GetODataPayloadSerializer(model, type, request));
                }
            }

            // In case user uses his own controller or NonFound error for request
            return(DefaultRestierSerializerProvider.SingletonInstance.GetODataPayloadSerializer(model, type, request));
        }
示例#11
0
        private ODataSerializer GetSerializer(Type type, object value, IEdmModel model, ODataSerializerProvider serializerProvider)
        {
            ODataSerializer serializer;

            IEdmObject edmObject = value as IEdmObject;

            if (edmObject != null)
            {
                IEdmTypeReference edmType = edmObject.GetEdmType();
                if (edmType == null)
                {
                    throw new SerializationException(Error.Format(SRResources.EdmTypeCannotBeNull,
                                                                  edmObject.GetType().FullName, typeof(IEdmObject).Name));
                }

                serializer = serializerProvider.GetEdmTypeSerializer(edmType);
                if (serializer == null)
                {
                    string message = Error.Format(SRResources.TypeCannotBeSerialized, edmType.ToTraceString(), typeof(ODataJsonSerializer).Name);
                    throw new SerializationException(message);
                }
            }
            else
            {
                // TODO: Support $apply
                // Currently don't support $apply
                //var applyClause = Request.ODataProperties().ApplyClause;
                //// get the most appropriate serializer given that we support inheritance.
                //if (applyClause == null)
                //{
                //	type = value == null ? type : value.GetType();
                //}

                serializer = serializerProvider.GetODataPayloadSerializer(model, type, Request);
                if (serializer == null)
                {
                    string message = Error.Format(SRResources.TypeCannotBeSerialized, type.Name, typeof(ODataJsonSerializer).Name);
                    throw new SerializationException(message);
                }
            }

            return(serializer);
        }
        private IEnumerable <KeyValuePair <string, string> > GetResponseMessageHeaders(Type graphType, ODataFormat odataFormat, ODataVersion version)
        {
            IODataResponseMessage responseMessage = new ODataMessageWrapper();

            ODataMessageWriterSettings writerSettings = new ODataMessageWriterSettings()
            {
                BaseUri = new Uri(ODataFormatterConstants.DefaultNamespace),
                Version = version,
                Indent  = false
            };

            writerSettings.SetContentType(odataFormat);
            using (ODataMessageWriter messageWriter = new ODataMessageWriter(responseMessage, writerSettings))
            {
                ODataSerializer serializer = ODataSerializerProvider.GetODataPayloadSerializer(graphType);

                // get the OData specific headers for the payloadkind
                ODataUtils.SetHeadersForPayload(messageWriter, serializer.ODataPayloadKind);
            }

            return(responseMessage.Headers);
        }
示例#13
0
        private ODataSerializer GetSerializer(Type type, object value, IEdmModel model, ODataSerializerProvider serializerProvider, HttpRequest request)
        {
            ODataSerializer serializer;

            IEdmObject edmObject = value as IEdmObject;

            if (edmObject != null)
            {
                IEdmTypeReference edmType = edmObject.GetEdmType();
                if (edmType == null)
                {
                    throw new SerializationException(Error.Format(SRResources.EdmTypeCannotBeNull,
                                                                  edmObject.GetType().FullName, typeof(IEdmObject).Name));
                }

                serializer = serializerProvider.GetEdmTypeSerializer(edmType);
                if (serializer == null)
                {
                    string message = Error.Format(SRResources.TypeCannotBeSerialized, edmType.ToTraceString(), typeof(ODataOutputFormatter).Name);
                    throw new SerializationException(message);
                }
            }
            else
            {
                // get the most appropriate serializer given that we support inheritance.
                type       = value == null ? type : value.GetType();
                serializer = serializerProvider.GetODataPayloadSerializer(model, type, request);
                if (serializer == null)
                {
                    string message = Error.Format(SRResources.TypeCannotBeSerialized, type.Name, typeof(ODataOutputFormatter).Name);
                    throw new SerializationException(message);
                }
            }

            return(serializer);
        }
示例#14
0
        public override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content,
                                                TransportContext transportContext, CancellationToken cancellationToken)
        {
            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }
            if (writeStream == null)
            {
                throw Error.ArgumentNull("writeStream");
            }
            if (Request == null)
            {
                throw Error.InvalidOperation(SRResources.WriteToStreamAsyncMustHaveRequest);
            }
            if (cancellationToken.IsCancellationRequested)
            {
                return(TaskHelpers.Canceled());
            }

            try
            {
                HttpConfiguration configuration = Request.GetConfiguration();
                if (configuration == null)
                {
                    throw Error.InvalidOperation(SRResources.RequestMustContainConfiguration);
                }

                HttpContentHeaders contentHeaders = (content == null) ? null : content.Headers;
                UrlHelper          urlHelper      = Request.GetUrlHelper() ?? new UrlHelper(Request);

                Func <ODataSerializerContext> getODataSerializerContext = () =>
                {
                    return(new ODataSerializerContext()
                    {
                        Request = Request,
                        Url = urlHelper,
                    });
                };

                ODataSerializerProvider serializerProvider = Request.GetRequestContainer()
                                                             .GetRequiredService <ODataSerializerProvider>();

                ODataOutputFormatterHelper.WriteToStream(
                    type,
                    value,
                    Request.GetModel(),
                    ResultHelpers.GetODataResponseVersion(Request),
                    GetBaseAddressInternal(Request),
                    contentHeaders == null ? null : contentHeaders.ContentType,
                    new WebApiUrlHelper(urlHelper),
                    new WebApiRequestMessage(Request),
                    new WebApiRequestHeaders(Request.Headers),
                    (services) => ODataMessageWrapperHelper.Create(writeStream, contentHeaders, services),
                    (edmType) => serializerProvider.GetEdmTypeSerializer(edmType),
                    (objectType) => serializerProvider.GetODataPayloadSerializer(objectType, Request),
                    getODataSerializerContext);

                return(TaskHelpers.Completed());
            }
            catch (Exception ex)
            {
                return(TaskHelpers.FromError(ex));
            }
        }
示例#15
0
        public void GetODataPayloadSerializer_ThrowsArgumentNull_Type()
        {
            // Arrange
            var request = RequestFactory.Create();

            // Act & Assert
            ExceptionAssert.ThrowsArgumentNull(
                () => _serializerProvider.GetODataPayloadSerializer(type: null, request: request),
                "type");
        }
        public override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content, TransportContext transportContext)
        {
            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }

            if (writeStream == null)
            {
                throw Error.ArgumentNull("writeStream");
            }

            HttpContentHeaders contentHeaders = content == null ? null : content.Headers;

            return(TaskHelpers.RunSynchronously(() =>
            {
                // Get the format and version to use from the ODataServiceVersion content header or if not available use the
                // values configured for the specialized formatter instance.
                ODataVersion version;
                ODataFormat odataFormat;
                if (contentHeaders == null)
                {
                    version = _defaultODataVersion;
                    odataFormat = ODataFormatterConstants.DefaultODataFormat;
                }
                else
                {
                    version = GetODataVersion(contentHeaders, ODataFormatterConstants.ODataServiceVersion) ?? _defaultODataVersion;
                    odataFormat = GetODataFormat(contentHeaders);
                }

                ODataSerializer serializer = ODataSerializerProvider.GetODataPayloadSerializer(type);
                if (serializer == null)
                {
                    throw Error.InvalidOperation(SRResources.TypeCannotBeSerialized, type.Name, typeof(ODataMediaTypeFormatter).Name);
                }

                if (IsClient)
                {
                    // TODO: Bug 467617: figure out the story for the operation name on the client side and server side.
                    string operationName = (value != null ? value.GetType() : type).Name;

                    // serialize a request
                    IODataRequestMessage requestMessage = new ODataMessageWrapper(writeStream);
                    ODataResponseContext responseContext = new ODataResponseContext(requestMessage, odataFormat, version, new Uri(ODataFormatterConstants.DefaultNamespace), operationName);

                    ODataMessageWriterSettings writerSettings = new ODataMessageWriterSettings()
                    {
                        BaseUri = responseContext.BaseAddress,
                        Version = responseContext.ODataVersion,
                        Indent = responseContext.IsIndented,
                        DisableMessageStreamDisposal = true,
                    };

                    writerSettings.SetContentType(responseContext.ODataFormat);
                    using (ODataMessageWriter messageWriter = new ODataMessageWriter(requestMessage, writerSettings, Model))
                    {
                        ODataSerializerWriteContext writeContext = new ODataSerializerWriteContext(responseContext);
                        serializer.WriteObject(value, messageWriter, writeContext);
                    }
                }
                else
                {
                    UrlHelper urlHelper = Request.GetUrlHelper();
                    NameValueCollection queryStringValues = Request.RequestUri.ParseQueryString();

                    IEdmEntitySet targetEntitySet = null;
                    ODataUriHelpers.TryGetEntitySetAndEntityType(Request.RequestUri, Model, out targetEntitySet);

                    ODataQueryProjectionNode rootProjectionNode = null;
                    if (targetEntitySet != null)
                    {
                        // TODO: Bug 467621: Move to ODataUriParser once it is done.
                        rootProjectionNode = ODataUriHelpers.GetODataQueryProjectionNode(queryStringValues["$select"], queryStringValues["$expand"], targetEntitySet);
                    }

                    // serialize a response
                    Uri baseAddress = new Uri(Request.RequestUri, Request.GetConfiguration().VirtualPathRoot);

                    // TODO: Bug 467617: figure out the story for the operation name on the client side and server side.
                    // This is clearly a workaround. We are assuming that the operation name is the last segment in the request uri
                    // which works for most cases and fall back to the type name of the object being written.
                    // We should rather use uri parser semantic tree to figure out the operation name from the request url.
                    string operationName = ODataUriHelpers.GetOperationName(Request.RequestUri, baseAddress);
                    operationName = operationName ?? type.Name;

                    IODataResponseMessage responseMessage = new ODataMessageWrapper(writeStream);
                    ODataResponseContext responseContext = new ODataResponseContext(responseMessage, odataFormat, version, baseAddress, operationName);

                    ODataMessageWriterSettings writerSettings = new ODataMessageWriterSettings()
                    {
                        BaseUri = responseContext.BaseAddress,
                        Version = responseContext.ODataVersion,
                        Indent = responseContext.IsIndented,
                        DisableMessageStreamDisposal = true,
                    };
                    if (contentHeaders != null && contentHeaders.ContentType != null)
                    {
                        writerSettings.SetContentType(contentHeaders.ContentType.ToString(), Encoding.UTF8.WebName);
                    }

                    using (ODataMessageWriter messageWriter = new ODataMessageWriter(responseMessage, writerSettings, ODataDeserializerProvider.EdmModel))
                    {
                        ODataSerializerWriteContext writeContext = new ODataSerializerWriteContext(responseContext)
                        {
                            EntitySet = targetEntitySet,
                            UrlHelper = urlHelper,
                            RootProjectionNode = rootProjectionNode,
                            CurrentProjectionNode = rootProjectionNode
                        };

                        serializer.WriteObject(value, messageWriter, writeContext);
                    }
                }
            }));
        }
示例#17
0
        /// <inheritdoc/>
        public override bool CanWriteResult(OutputFormatterCanWriteContext context)
        {
            if (context == null)
            {
                throw Error.ArgumentNull("context");
            }

            // Ensure we have a valid request.
            HttpRequest request = context.HttpContext.Request;

            if (request == null)
            {
                throw Error.InvalidOperation(SRResources.ReadFromStreamAsyncMustHaveRequest);
            }

            // Ignore non-OData requests.
            if (request.ODataFeature().Path == null)
            {
                return(false);
            }

            // The following base.CanWriteResult(context) will change the context.ContentType
            // If this formatter can't write the result, we should reset the context.ContentType to its original value.
            // So that, the other formatter can make a descison based on the original content type.
            // Be noted: in .NET 5, the context.ContentType is a new StringSegment everytime when goes into each formatter
            // formatterContext.ContentType = new StringSegment();
            // So, in .NET 5, we don't need to reset the contentType to backupContentType.
            StringSegment backupContentType = context.ContentType;

            // Allow the base class to make its determination, which includes
            // checks for SupportedMediaTypes.
            bool suportedMediaTypeFound = false;

            if (SupportedMediaTypes.Any())
            {
                suportedMediaTypeFound = base.CanWriteResult(context);
            }

            // See if the request satisfies any mappings.
            IEnumerable <MediaTypeMapping> matchedMappings = (MediaTypeMappings == null) ? null : MediaTypeMappings
                                                             .Where(m => (m.TryMatchMediaType(request) > 0));

            // Now pick the best content type. If a media mapping was found, use that and override the
            // value specified by the controller, if any. Otherwise, let the base class decide.
            if (matchedMappings != null && matchedMappings.Any())
            {
                context.ContentType = matchedMappings.First().MediaType.ToString();
            }
            else if (!suportedMediaTypeFound)
            {
                context.ContentType = backupContentType;
                return(false);
            }

            // We need the type in order to write it.
            Type type = context.ObjectType ?? context.Object?.GetType();

            if (type == null)
            {
                context.ContentType = backupContentType;
                return(false);
            }
            type = TypeHelper.GetTaskInnerTypeOrSelf(type);

            ODataSerializerProvider serializerProvider = request.GetRequestContainer().GetRequiredService <ODataSerializerProvider>();

            // See if this type is a SingleResult or is derived from SingleResult.
            bool isSingleResult = false;

            if (type.IsGenericType)
            {
                Type genericType = type.GetGenericTypeDefinition();
                Type baseType    = TypeHelper.GetBaseType(type);
                isSingleResult = (genericType == typeof(SingleResult <>) || baseType == typeof(SingleResult));
            }

            bool result = ODataOutputFormatterHelper.CanWriteType(
                type,
                _payloadKinds,
                isSingleResult,
                new WebApiRequestMessage(request),
                (objectType) => serializerProvider.GetODataPayloadSerializer(objectType, request));

            if (!result)
            {
                context.ContentType = backupContentType;
            }

            return(result);
        }
示例#18
0
        public override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content, TransportContext transportContext)
        {
            if (type == null)
            {
                throw Error.ArgumentNull("type");
            }

            if (writeStream == null)
            {
                throw Error.ArgumentNull("writeStream");
            }

            if (Request == null)
            {
                throw Error.NotSupported(SRResources.WriteToStreamAsyncMustHaveRequest);
            }

            HttpContentHeaders contentHeaders = content == null ? null : content.Headers;

            return(TaskHelpers.RunSynchronously(() =>
            {
                // Get the format and version to use from the ODataServiceVersion content header or if not available use the
                // values configured for the specialized formatter instance.
                ODataVersion version;
                if (contentHeaders == null)
                {
                    version = _defaultODataVersion;
                }
                else
                {
                    version = GetODataVersion(contentHeaders, ODataFormatterConstants.ODataServiceVersion) ?? _defaultODataVersion;
                }

                // get the most appropriate serializer given that we support inheritance.
                type = value == null ? type : value.GetType();
                ODataSerializer serializer = ODataSerializerProvider.GetODataPayloadSerializer(type);
                if (serializer == null)
                {
                    throw Error.InvalidOperation(SRResources.TypeCannotBeSerialized, type.Name, typeof(ODataMediaTypeFormatter).Name);
                }

                UrlHelper urlHelper = Request.GetUrlHelper();

                IEdmEntitySet targetEntitySet = null;
                ODataUriHelpers.TryGetEntitySetAndEntityType(Request.RequestUri, Model, out targetEntitySet);

                // serialize a response
                Uri baseAddress = new Uri(Request.RequestUri, Request.GetConfiguration().VirtualPathRoot);

                // TODO: Bug 467617: figure out the story for the operation name on the client side and server side.
                // This is clearly a workaround. We are assuming that the operation name is the last segment in the request uri
                // which works for most cases and fall back to the type name of the object being written.
                // We should rather use uri parser semantic tree to figure out the operation name from the request url.
                string operationName = ODataUriHelpers.GetOperationName(Request.RequestUri, baseAddress);
                operationName = operationName ?? type.Name;

                IODataResponseMessage responseMessage = new ODataMessageWrapper(writeStream);

                // TODO: Issue 483: http://aspnetwebstack.codeplex.com/workitem/483
                // We need to set the MetadataDocumentUri when this property is added to ODataMessageWriterSettings as
                // part of the JSON Light work.
                // This is required so ODataLib can coerce AbsoluteUri's into RelativeUri's when appropriate in JSON Light.
                ODataMessageWriterSettings writerSettings = new ODataMessageWriterSettings()
                {
                    BaseUri = baseAddress,
                    Version = version,
                    Indent = true,
                    DisableMessageStreamDisposal = true
                };

                if (contentHeaders != null && contentHeaders.ContentType != null)
                {
                    writerSettings.SetContentType(contentHeaders.ContentType.ToString(), Encoding.UTF8.WebName);
                }

                using (ODataMessageWriter messageWriter = new ODataMessageWriter(responseMessage, writerSettings, ODataDeserializerProvider.EdmModel))
                {
                    ODataSerializerContext writeContext = new ODataSerializerContext()
                    {
                        EntitySet = targetEntitySet,
                        UrlHelper = urlHelper,
                        ServiceOperationName = operationName,
                        SkipExpensiveAvailabilityChecks = serializer.ODataPayloadKind == ODataPayloadKind.Feed,
                        Request = Request
                    };

                    serializer.WriteObject(value, messageWriter, writeContext);
                }
            }));
        }