/// <summary>
/// Parses the first 8 or 9 bytes from multiple buffers and returns a FrameHeader
/// </summary>
public static FrameHeader ParseResponseHeader(ProtocolVersion version, byte[] buffer1, byte[] buffer2)
{
var headerBuffer = new byte[!version.Uses2BytesStreamIds() ? 8 : 9];
Buffer.BlockCopy(buffer1, 0, headerBuffer, 0, buffer1.Length);
Buffer.BlockCopy(buffer2, 0, headerBuffer, buffer1.Length, headerBuffer.Length - buffer1.Length);
return(ParseResponseHeader(version, headerBuffer, 0));
}
/// <summary>
/// Gets the size of the protocol header, depending on the version of the protocol
/// </summary>
/// <param name="version">Version of the protocol used</param>
public static byte GetSize(ProtocolVersion version)
{
if (version.Uses2BytesStreamIds())
{
return(9);
}
return(8);
}
public static int GetHeaderSize(this ProtocolVersion version)
{
if (version.Uses2BytesStreamIds())
{
return(9);
}
return(8);
}
/// <summary>
/// Writes the frame header, leaving body length to 0
/// </summary>
public void WriteFrameHeader(byte flags, short streamId, byte opCode)
{
byte[] header;
if (!_version.Uses2BytesStreamIds())
{
//8 bytes for the header, dedicating 1 for the streamId
if (streamId > 127)
{
throw new ArgumentException("StreamId must be smaller than 128 under protocol version " + _version);
}
header = new byte[]
{
(byte)_version,
flags,
(byte)streamId,
opCode,
//Reserved for the body length
0, 0, 0, 0
};
Write(header);
return;
}
//9 bytes for the header, dedicating 2 for the streamId
var streamIdBytes = BeConverter.GetBytes(streamId);
header = new byte[]
{
(byte)_version,
flags,
streamIdBytes[0],
streamIdBytes[1],
opCode,
//Reserved for the body length
0, 0, 0, 0
};
Write(header);
}
/// <summary>
/// Creates a new instance of <see cref="PoolingOptions"/> using the default amount of connections
/// and settings based on the protocol version.
/// <para>
/// For modern server versions (Apache Cassandra 2.1+) the amount of core connections are set to 1,
/// setting 2 for max local connections.
/// </para>
/// </summary>
/// <returns>A new instance of <see cref="PoolingOptions"/></returns>
/// <seealso cref="ProtocolVersion"/>
public static PoolingOptions Create(ProtocolVersion protocolVersion = ProtocolVersion.MaxSupported)
{
if (!protocolVersion.Uses2BytesStreamIds())
{
//New instance of pooling options with default values
return(new PoolingOptions());
}
//New instance of pooling options with default values for high number of concurrent requests
return(new PoolingOptions()
.SetCoreConnectionsPerHost(HostDistance.Local, 1)
.SetMaxConnectionsPerHost(HostDistance.Local, 2)
.SetCoreConnectionsPerHost(HostDistance.Remote, 1)
.SetMaxConnectionsPerHost(HostDistance.Remote, 1)
.SetMaxSimultaneousRequestsPerConnectionTreshold(HostDistance.Local, 1500)
.SetMaxSimultaneousRequestsPerConnectionTreshold(HostDistance.Remote, 1500));
}
/// <summary>
/// Parses the first 8 or 9 bytes and returns a FrameHeader
/// </summary>
public static FrameHeader ParseResponseHeader(ProtocolVersion version, byte[] buffer, int offset)
{
var header = new FrameHeader()
{
_versionByte = buffer[offset++],
Flags = (HeaderFlag)buffer[offset++]
};
if (!version.Uses2BytesStreamIds())
{
//Stream id is a signed byte in v1 and v2 of the protocol
header.StreamId = (sbyte)buffer[offset++];
}
else
{
header.StreamId = BeConverter.ToInt16(buffer, offset);
offset += 2;
}
header.Opcode = buffer[offset++];
header.BodyLength = BeConverter.ToInt32(Utils.SliceBuffer(buffer, offset, 4));
return(header);
}
/// <summary>
/// Gets a buffer containing 8 bytes for header and 4 bytes for the body.
/// For result + void response message (protocol v2)
/// </summary>
private static byte[] GetResultBuffer(short streamId, ProtocolVersion version = ProtocolVersion.V2)
{
var header = (byte)((int)version | 0x80);
if (version.Uses2BytesStreamIds())
{
var bytes = BeConverter.GetBytes(streamId);
return(new byte[]
{
//header
header, 0, bytes[0], bytes[1], ResultResponse.OpCode, 0, 0, 0, 4,
//body
0, 0, 0, 1
});
}
return(new byte[]
{
//header
header, 0, (byte)streamId, ResultResponse.OpCode, 0, 0, 0, 4,
//body
0, 0, 0, 1
});
}
