public void WriteRecord(Message <TKey, TValue> message, IBufferWriter <byte> output)
{
// Record...
// length: varint
// attributes: int8
// bit 0~7: unused
// timestampDelta: varint
// offsetDelta: varint
// keyLength: varint
// key: byte[]
// valueLen: varint
// value: byte[]
// Headers => [Header]
// Header...
// headerKeyLength: varint
// headerKey: String
// headerValueLength: varint
// Value: byte[]
using var buffer = new MemoryBufferWriter();
buffer.WriteByte(0); // attributes: int8 - bit 0~7: unused
buffer.WriteVarInt((uint)0); // timestampDelta: varint
buffer.WriteVarInt((uint)0); // offsetDelta: varint
buffer.WritePrefixed(keySerializer, message.Key, BufferWriterExtensions.PrefixType.VarInt);
buffer.WritePrefixed(valueSerializer, message.Value, BufferWriterExtensions.PrefixType.VarInt);
// headers
buffer.WriteVarInt((ulong)message.HeadersCount);
message.ForEachHeader(h =>
{
buffer.WriteCompactString(h.Key);
buffer.WritePrefixed(h.Value.AsSpan(), BufferWriterExtensions.PrefixType.VarInt);
});
output.WriteVarInt(buffer.Length);
buffer.CopyTo(output);
}