/// <summary>
/// Read the start of the top-level data wrapper in JSON responses.
/// </summary>
/// <param name="payloadKind">The kind of payload we are reading; this guides the parsing of the metadata URI.</param>
/// <param name="duplicatePropertyNamesChecker">The duplicate property names checker.</param>
/// <param name="isReadingNestedPayload">true if we are deserializing a nested payload, e.g. an entry, a feed or a collection within a parameters payload.</param>
/// <param name="allowEmptyPayload">true if we allow a comletely empty payload; otherwise false.</param>
/// <returns>The parsed metadata URI.</returns>
/// <remarks>
/// Pre-Condition: JsonNodeType.None: assumes that the JSON reader has not been used yet when not reading a nested payload.
/// Post-Condition: The reader is positioned on the first property of the payload after having read (or skipped) the metadata URI property.
/// Or the reader is positioned on an end-object node if there are no properties (other than the metadata URI which is required in responses and optional in requests).
/// </remarks>
internal Task ReadPayloadStartAsync(
ODataPayloadKind payloadKind,
DuplicatePropertyNamesChecker duplicatePropertyNamesChecker,
bool isReadingNestedPayload,
bool allowEmptyPayload)
{
DebugUtils.CheckNoExternalCallers();
this.JsonReader.AssertNotBuffering();
Debug.Assert(isReadingNestedPayload || this.JsonReader.NodeType == JsonNodeType.None, "Pre-Condition: JSON reader must not have been used yet when not reading a nested payload.");
return(TaskUtils.GetTaskForSynchronousOperation(() =>
{
string metadataUriAnnotationValue = this.ReadPayloadStartImplementation(
payloadKind,
duplicatePropertyNamesChecker,
isReadingNestedPayload,
allowEmptyPayload);
// The metadata URI is only recognized in non-error response top-level payloads.
// If the payload is nested (for example when we read URL literals) we don't recognize the metadata URI.
// Top-level error payloads don't need and use the metadata URI.
if (!isReadingNestedPayload && payloadKind != ODataPayloadKind.Error)
{
this.metadataUriParseResult = this.jsonLightInputContext.PayloadKindDetectionState == null
? null
: this.jsonLightInputContext.PayloadKindDetectionState.MetadataUriParseResult;
if (this.metadataUriParseResult == null && metadataUriAnnotationValue != null)
{
this.metadataUriParseResult = ODataJsonLightMetadataUriParser.Parse(
this.Model,
metadataUriAnnotationValue,
payloadKind,
this.Version,
this.MessageReaderSettings.ReaderBehavior);
}
}
#if DEBUG
this.metadataUriParseResultReady = true;
#endif
}));
}
/// <summary>
/// Creates a metadata URI parser and parses the metadata URI read from the payload.
/// </summary>
/// <param name="model">The model to use when resolving the target of the URI.</param>
/// <param name="metadataUriFromPayload">The string value of the odata.metadata annotation read from the payload.</param>
/// <param name="payloadKind">The payload kind we expect the metadata URI to conform to.</param>
/// <param name="version">The OData version to use for determining the set of built-in functions available.</param>
/// <param name="readerBehavior">Reader behavior if the caller is a reader, null if no reader behavior is available.</param>
/// <returns>The result from parsing the metadata URI.</returns>
internal static ODataJsonLightMetadataUriParseResult Parse(
IEdmModel model,
string metadataUriFromPayload,
ODataPayloadKind payloadKind,
ODataVersion version,
ODataReaderBehavior readerBehavior)
{
DebugUtils.CheckNoExternalCallers();
if (metadataUriFromPayload == null)
{
throw new ODataException(ODataErrorStrings.ODataJsonLightMetadataUriParser_NullMetadataDocumentUri);
}
// Create an absolute URI from the payload string
Uri metadataUri = new Uri(metadataUriFromPayload, UriKind.Absolute);
ODataJsonLightMetadataUriParser parser = new ODataJsonLightMetadataUriParser(model, metadataUri);
parser.TokenizeMetadataUri();
parser.ParseMetadataUri(payloadKind, readerBehavior, version);
return(parser.parseResult);
}
