unicast

Unicast implementation of UDP Datagram sockets.

Usage

const unicast = require('unicast')
const fs = require('fs')

const socket = unicast.createSocket({
  type: 'udp4',
  port: 2222,
  remotePort: 1111,
  remoteAddress: '127.0.0.1'
})

// now the `socket` can receive packets ONLY
// from 127.0.0.1:1111

socket.pipe(fs.createWriteStream('log.txt', { encoding: 'utf8' }))

API

• createSocket(socket: dgram.Socket, options: Options): Socket
• createSocket(options: Options): Socket

Creates an unicast UDP Datagram socket. A createSocket() function also accept all options for dgram.createSocket(). If socket is provided, these options will be ignored.

• options.remotePort: number

The numeric representation of the remote port.

• options.remoteAddress: string

The string representation of the remote IP address.

• options.socket: dgram.Socket

An optional internal dgram socket used as transport layer.

• options.port: number [default = 0]

The string representation of the local IP address. If port is not specified or is 0, the operating system will attempt to bind to a random port.

• options.address: string [default = 0.0.0.0]

The string representation of the local IP address. If address is not specified or is 0.0.0.0, the operating system will attempt to listen on all addresses.

• options.closeTransport: boolean [default = true]

The internal socket will be closed when the unicast.Socket is being closed. You can change this behavior with this option.

• options.messagesFilter: function(socket: Socket, message: Buffer, rinfo: Object): bool

Custom filter of an incoming messages. By default it check the remote IP address and the remote port.

• class Socket

This class is an abstraction of an unicast UDP socket. A Socket is also a duplex stream, so it can be both readable and writable, and it is also a EventEmitter.

• socket.close()

Close the underlying socket and stop listening for data on it.

• socket.unshift(message: Buffer): bool

The socket.unshift() method pushes a chunk of data back into the internal buffer. This is useful in certain situations where a stream is being consumed by code that needs to "un-consume" some amount of data that it has optimistically pulled out of the source, so that the data can be passed on to some other party.

• socket.process(message: Buffer): bool

The socket.process() method helps to handle a chunk of data from an another source. Almost the same as socket.unshift() but pushes a chunk of data into the end of the internal buffer.

• socket.localAddress: string

The string representation of the local IP address. For example, 74.125.127.100 or 2001:4860:a005::68.

• socket.localPort: number

The numeric representation of the local port. For example, 80 or 21.

• get/set socket.remoteAddress: string

The string representation of the remote IP address. For example, 74.125.127.100 or 2001:4860:a005::68.

• get/set socket.remotePort: number

The numeric representation of the remote port. For example, 80 or 21.

License

MIT, 20!8 (c) Dmitriy Tsvettsikh