/// <summary>
/// Constructs a Message for the given <code>payload</code> and <code>meta data</code>. The given <code>metaData</code> is
/// merged with the MetaData from the correlation data of the current unit of work, if present.
/// </summary>
/// <param name="declaredPayloadType">The declared type of message payload</param>
/// <param name="payload">The payload for the message</param>
/// <param name="metaData">The meta data for the message</param>
public GenericMessage(Type declaredPayloadType,
T?payload,
IImmutableDictionary <string, object> metaData) : this(
IdentifierFactory.GetInstance().GenerateIdentifier(),
declaredPayloadType,
payload,
CurrentUnitOfWork <IMessage <T>, T> .CorrelationData().MergedWith(MetaData.From(metaData))
)
{
}