Beispiel #1
0
        /// <summary>
        /// Synchronizely get the query set count from the server by executing the $count=value query
        /// </summary>
        /// <param name="context">The context</param>
        /// <returns>The server side count of the query set</returns>
        internal long GetQuerySetCount(DataServiceContext context)
        {
            Debug.Assert(null != context, "context is null");
            Version requestVersion = this.QueryComponents(context.Model).Version;

            if (requestVersion == null)
            {
                requestVersion = Util.ODataVersion4;
            }

            QueryResult               response       = null;
            QueryComponents           qc             = this.QueryComponents(context.Model);
            Uri                       requestUri     = qc.Uri;
            DataServiceRequest <long> serviceRequest = new DataServiceRequest <long>(requestUri, qc, null);

            HeaderCollection headers = new HeaderCollection();

            // Validate and set the request DSV header
            headers.SetRequestVersion(requestVersion, context.MaxProtocolVersionAsVersion);
            context.Format.SetRequestAcceptHeaderForCount(headers);

            string httpMethod = XmlConstants.HttpMethodGet;
            ODataRequestMessageWrapper request = context.CreateODataRequestMessage(
                context.CreateRequestArgsAndFireBuildingRequest(httpMethod, requestUri, headers, context.HttpStack, null /*descriptor*/),
                null /*descriptor*/);

            response = new QueryResult(this, Util.ExecuteMethodName, serviceRequest, request, new RequestInfo(context), null, null);

            try
            {
                response.ExecuteQuery();

                if (HttpStatusCode.NoContent != response.StatusCode)
                {
                    StreamReader sr = new StreamReader(response.GetResponseStream());
                    long         r  = -1;
                    try
                    {
                        r = XmlConvert.ToInt64(sr.ReadToEnd());
                    }
                    finally
                    {
                        sr.Close();
                    }

                    return(r);
                }
                else
                {
                    throw new DataServiceQueryException(Strings.DataServiceRequest_FailGetCount, response.Failure);
                }
            }
            catch (InvalidOperationException ex)
            {
                QueryOperationResponse operationResponse = null;
                operationResponse = response.GetResponse <long>(MaterializeAtom.EmptyResults);
                if (null != operationResponse)
                {
                    operationResponse.Error = ex;
                    throw new DataServiceQueryException(Strings.DataServiceException_GeneralError, ex, operationResponse);
                }

                throw;
            }
        }