// custom deserializer with no dependency on the Serializer subsystem
// order of fields is important for backwards compat and must be the same as the order in Serialize, don't change!
// This method is static because the entry type differentiator is not the first field, and we need to read several
// fields before we can decide what type to create. This is for legacy reasons, since the early versions of the
// catalog file only contained one type of entry (stream metadata).
internal static Metadata Deserialize(BufferReader metadataBuffer)
{
var name = metadataBuffer.ReadString();
var id = metadataBuffer.ReadInt32();
var typeName = metadataBuffer.ReadString();
var version = metadataBuffer.ReadInt32();
var serializerTypeName = metadataBuffer.ReadString();
var serializerVersion = metadataBuffer.ReadInt32();
var customFlags = metadataBuffer.ReadUInt16();
var kind = (MetadataKind)metadataBuffer.ReadUInt16();
if (kind == MetadataKind.StreamMetadata)
{
var result = new PsiStreamMetadata(name, id, typeName, version, serializerTypeName, serializerVersion, customFlags);
result.Deserialize(metadataBuffer);
return(result);
}
else if (kind == MetadataKind.TypeSchema)
{
var result = new TypeSchema(name, id, typeName, version, serializerTypeName, serializerVersion);
result.Deserialize(metadataBuffer);
return(result);
}
else
{
// kind == MetadataKind.RuntimeInfo
var result = new RuntimeInfo(name, id, typeName, version, serializerTypeName, serializerVersion);
return(result);
}
}
/// <summary>
/// Returns the metadata associated with the specified stream, if the stream is persisted to a store.
/// </summary>
/// <param name="pipeline">The current pipeline</param>
/// <param name="streamName">The name of the stream to retrieve metadata about</param>
/// <param name="metadata">Upon return, this parameter contains the metadata associated with the stream, or null if the stream is not persisted</param>
/// <returns>True if the stream is persisted to a store, false otherwise</returns>
public static bool TryGetMetadata(Pipeline pipeline, string streamName, out PsiStreamMetadata metadata)
{
if (string.IsNullOrEmpty(streamName))
{
metadata = null;
return(false);
}
return(pipeline.ConfigurationStore.TryGet(StreamMetadataNamespace, streamName, out metadata));
}
/// <summary>
/// Update supplemental stream metadata from another stream metadata.
/// </summary>
/// <param name="other">Other stream metadata from which to copy supplemental metadata.</param>
/// <returns>Updated stream metadata.</returns>
internal PsiStreamMetadata UpdateSupplementalMetadataFrom(PsiStreamMetadata other)
{
this.SupplementalMetadataTypeName = other.SupplementalMetadataTypeName;
this.supplementalMetadataBytes = other.supplementalMetadataBytes;
return(this);
}
/// <summary>
/// Returns the metadata associated with the specified stream, if the stream is persisted to a store.
/// </summary>
/// <typeparam name="T">The type of stream messages</typeparam>
/// <param name="source">The stream to retrieve metadata about</param>
/// <param name="metadata">Upon return, this parameter contains the metadata associated with the stream, or null if the stream is not persisted</param>
/// <returns>True if the stream is persisted to a store, false otherwise</returns>
public static bool TryGetMetadata <T>(IProducer <T> source, out PsiStreamMetadata metadata)
{
return(Store.TryGetMetadata(source.Out.Pipeline, source.Out.Name, out metadata));
}
