@shardeum-foundation/net

shardus-net

A library for sending and receiving JSON messages over raw TCP sockets.

Fundamentally, this is just a networked event emitter. Under the hood, the library is using a UUID system to correlate messages to their response handler in order to facilitate the simulation of a request/response system. Hence, the library can only be used to send data to and from other servers using this library (for now).

Installation

You can install shardus net via npm:

npm i gitlab:shardus/shardus-net

Local Development

If you're working on the shardus-net package, make sure to run the command npm run build manually to ensure both TypeScript and Rust files are generated.

For publishing a release to NPM, simply run npm run release command.

Usage

Javascript

const port = 1234
const address = 'localhost'

const sn = require('shardus-net')({ port, address })

Typescript

import * as ShardusNet from 'shardus-net'

const port = 1234
const address = 'localhost'
const sn = ShardusNet.createNetwork({ port, address })

sn.send

// If you want to send a one-way message, not expecting a response:
const destinationPort    = 53
const destinationAddress = 8.8.8.8
const data               = { algebraic: 'Yeah!' }

const protocol = await sn.send(destinationPort, destinationAddress, data)

// Note: the promise returned by sn.send will resolve once the data has been
//       successfully sent, and has nothing to do with a response.

// Now, if you _are_ expecting a response:
const destinationPort    = 53
const destinationAddress = 8.8.8.8
const data               = { mathematical: 'Alright!' }
const timeout            = 10000 // how long to wait for the response (in ms)

// Note: If the timeout is set to 0, the library will assume you're not waiting
//       for a response.

const onResponse = data => console.log(data)
const onTimeout  = () => throw new Error('timed out :(')

// You must be listening in order to receive responses, even if you don't
// do anything with incoming data. In a normal use case, you will already
// have a listener set up and do not need to execute this step.
await sn.listen(() => {})

const protocol = await sn.send(destinationPort, destinationAddress, data, timeout, onResponse, onTimeout)

// Assuming the server you send to bounces back the data (see below for how to do this),
// your console will log: "{ mathematical: 'Alright!' }"

sn.listen

const server = await sn.listen((data, remote, protocol, respond) => {
  // `remote` is an object with { address: <sender's address>, port: <origin port> }
  // Note: The port is of virtually no use -- it represents the port that data was
  //       send _from_, and you cannot send anything back to that port.

  // `data` is of course whatever you've been sent. You've got mail!

  // `respond` is the function you can use to send data back.

  // In this example, we'll use respond to simply bounce back the data we were
  // given. This completes the example from `send` above.
  await respond(data)
})

// You now have access to the "server" object, which contains the lower level
// net server, if you need it.

sn.stopListening

// When you want to spin down your listener, simply call stopListening and pass in
// the server object you were given when you started listening.

await sn.stopListening(servers)

Contributing

Contributions are very welcome! Everyone interacting in our codebases, issue trackers, and any other form of communication, including chat rooms and mailing lists, is expected to follow our code of conduct so we can all enjoy the effort we put into this project.

Special thanks to Aaron Sullivan ([e-mail]) for the contributions that became the base for this library. You can find them here at https://gitlab.com/Shardus/shardus-quic-net.git