Fast RPC for browser and Node.js based on TCP, WebSocket, and MDSF

143
10
JavaScript
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JSTP / JavaScript Transfer Protocol

JSTP is an RPC protocol and framework which provides two-way asynchronous data
transfer with support of multiple parallel non-blocking interactions that is so
transparent that an app may not even distinguish between local async functions
and remote procedures.

And, as a nice bonus, there’s a blazing fast JSON5
implementation bundled in!

This project is bound by a Code of Conduct.

Installation

JSTP works in Node.js and web browsers:

$ npm install --save @metarhia/jstp

Or, alternatively, there is
jstp.umd.js
UMD bundle.

We also have official client-side implementations for
Swift and
Java
that work effortlessly on iOS and Android πŸŽ‰

There is also an interactive CLI provided by this package:

$ npm install -g @metarhia/jstp
$ jstp-cli

Getting Started

Server:

'use strict';

const jstp = require('@metarhia/jstp');

// Application is the core high-level abstraction of the framework. An app
// consists of a number of interfaces, and each interface has its methods.
const app = new jstp.Application('testApp', {
  someService: {
    sayHi(connection, name, callback) {
      callback(null, `Hi, ${name}!`);
    },
  },
});

// Let's create a TCP server for this app. Other available transports are
// WebSocket and Unix domain sockets. One might notice that an array of
// applications is passed the `createServer()`. That's because it can serve
// any number of applications.
const server = jstp.net.createServer([app]);
server.listen(3000, () => {
  console.log('TCP server listening on port 3000 πŸš€');
});

Client:

'use strict';

const jstp = require('@metarhia/jstp');

// Create a TCP connection to server and connect to the `testApp` application.
// Clients can have applications too for full-duplex RPC,
// but we don't need that in this example. Client is `null` in this example,
// this implies that username and password are both `null`
// here β€” that is, the protocol-level authentication is not leveraged in this
// example. The next argument is an array of interfaces to inspect and build
// remote proxy objects for. Remaining arguments are for
// net.connect (host and port) and last argument is a callback
// to be called on successful connection or error.
jstp.net.connectAndInspect(
  'testApp',
  null,
  ['someService'],
  3000,
  'localhost',
  handleConnect
);

function handleConnect(error, connection, app) {
  if (error) {
    console.error(`Could not connect to the server: ${error}`);
    return;
  }

  // The `app` object contains remote proxy objects for each interface that has
  // been requested which allow to use remote APIs as regular async functions.
  // Remote proxies are also `EventEmitter`s: they can be used to `.emit()`
  // events to another side of a connection and listen to them using `.on()`.
  app.someService.sayHi('JSTP', (error, message) => {
    if (error) {
      console.error(`Oops, something went wrong: ${error}`);
      return;
    }
    console.log(`Server said "${message}" 😲`);
  });
}

Project Maintainers

Kudos to @tshemsedinov for the initial idea
and proof-of-concept implementation. Current project team is: