/// <summary>
        /// Web Method that is used to retrieve <c>SDMX</c> structure based on a <c>SDMX</c> query
        /// </summary>
        /// <param name="request">
        /// The <c>SDMX</c> query
        /// </param>
        /// <returns>
        /// The queried structure in <c>SDMX</c> SDMX-ML v2.1  format
        /// </returns>
        public Message DefaultHandler(Message request)
        {
            var soapOperation = request.GetSoapOperation();
            if (soapOperation != SoapOperation.Null)
            {
                // TODO handle those.
                throw _messageFaultBuilder.BuildException(new SdmxNotImplementedException("Method not implemented"), soapOperation.ToString());
            }

            throw _messageFaultBuilder.BuildException(new SdmxSyntaxException(string.Format(CultureInfo.InvariantCulture, "Syntax error: invalid operation {0}", soapOperation)), soapOperation.ToString());
        }