/// <summary>
/// Detects the payload kind(s) from the message stream.
/// </summary>
/// <param name="messageInfo">The context information for the message.</param>
/// <param name="settings">Configuration settings of the OData reader.</param>
/// <returns>An enumerable of zero or one payload kinds depending on whether the metadata payload kind was detected or not.</returns>
private static IEnumerable <ODataPayloadKind> DetectPayloadKindImplementation(
ODataMessageInfo messageInfo,
ODataMessageReaderSettings settings)
{
var detectionInfo = new ODataPayloadKindDetectionInfo(messageInfo, settings);
try
{
using (var reader = ODataMetadataReaderUtils.CreateXmlReader(
messageInfo.MessageStream, detectionInfo.GetEncoding(), detectionInfo.MessageReaderSettings))
{
if (reader.TryReadToNextElement() &&
string.CompareOrdinal(EdmConstants.EdmxName, reader.LocalName) == 0 &&
reader.NamespaceURI == EdmConstants.EdmxOasisNamespace)
{
return(new ODataPayloadKind[] { ODataPayloadKind.MetadataDocument });
}
}
}
catch (XmlException)
{
// If we are not able to read the payload as XML it is not a metadata document.
// Return no detected payload kind below.
}
return(Enumerable.Empty <ODataPayloadKind>());
}
/// <summary>Constructor.</summary>
/// <param name="messageInfo">The context information for the message.</param>
/// <param name="messageReaderSettings">Configuration settings of the OData reader.</param>
public ODataMetadataInputContext(
ODataMessageInfo messageInfo,
ODataMessageReaderSettings messageReaderSettings)
: base(ODataFormat.Metadata, messageInfo, messageReaderSettings)
{
Debug.Assert(messageInfo.MessageStream != null, "messageInfo.MessageStream != null");
try
{
// Which encoding do we use when reading XML payloads
this.baseXmlReader = ODataMetadataReaderUtils.CreateXmlReader(messageInfo.MessageStream, messageInfo.Encoding, messageReaderSettings);
// We use the buffering reader here only for in-stream error detection (not for buffering).
this.xmlReader = new BufferingXmlReader(
this.baseXmlReader,
/*parentXmlReader*/ null,
messageReaderSettings.BaseUri,
/*disableXmlBase*/ false,
messageReaderSettings.MessageQuotas.MaxNestingDepth);
}
catch (Exception e)
{
// Dispose the message stream if we failed to create the input context.
if (ExceptionUtils.IsCatchableExceptionType(e))
{
messageInfo.MessageStream.Dispose();
}
throw;
}
}
