public void WriteMessage(
HubMessage message,
IBufferWriter <byte> output,
IReadOnlyDictionary <Type, int> protobufTypeToIndexMap
)
{
var itemsMetadata = CreateItems(message)
.Select(item => ItemMetadata.Create(item, protobufTypeToIndexMap))
.ToList();
var metadata = new MessageMetadata
{
Items = { itemsMetadata }
};
var metadataByteSize = metadata.CalculateSize();
var totalByteSize = 4 // Total byte size (int)
+ 4 + metadataByteSize // Metadata byte size (int) and metadata itself
+ itemsMetadata
.Select(itemMetadata => itemMetadata.CalculateTotalSizeBytes())
.Sum(); // Total bytes of the protobuf models
var byteArray = ArrayPool <byte> .Shared.Rent(totalByteSize);
try
{
using (var outputStream = new MemoryStream(byteArray))
{
// Total byte size
outputStream.Write(BitConverter.GetBytes(totalByteSize), 0, 4);
// Metadata byte size
outputStream.Write(BitConverter.GetBytes(metadataByteSize), 0, 4);
// Metadata
metadata.WriteTo(outputStream);
// Other protobufs
foreach (var protobufItem in metadata.Items.SelectMany(item => item.NonNullProtobufs))
{
protobufItem.WriteTo(outputStream);
}
}
output.Write(new ReadOnlySpan <byte>(byteArray, 0, totalByteSize));
}
finally
{
ArrayPool <byte> .Shared.Return(byteArray);
}
}
