1.0.3 • Public • Published

Webworker Transport for Mole RPC (JSON RPC Library)

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Offload intensive calculations to WebWorker with just several lines of code.

Mole-RPC is a tiny transport agnostic JSON-RPC 2.0 client and server which can work both in NodeJs, Browser, Electron etc.

This is WebWorker based transport but there are many more transports.

What is the reason of using JSON-RPC for WebWorkers?

People usually send data to WebWorker in a form like {id, method, params} in JSON format via postMessage. As a result they expect {id, result}. And this is what JSON RPC is. id is required when you send several request and need to map results and requests.

So, why to write own solution every time? This transport allows you use JSON RPC for calling methods in WebWorkers. Moreover, it will handle all of edge-cases like errors processing, timeouts, batch calls, bidirectional communication etc.

Mole-RPC has zero dependencies and is a very small library.

Usage example (with simplified API)


import expose from 'mole-rpc-transport-webworker/expose';

const sum = (a, b) => a + b;
const multiply = (a, b) => a * b;

expose({ sum, multiply }).catch(console.error);


import createClient from 'mole-rpc-transport-webworker/createClient';

async function main() {
  const client = createClient(new Worker('worker.js'));
  const result = await client.sum(2, 3);

main().then(console.log, console.error);

You can pass extra Mole-RPC options to createClient as second parameter.

For example

const client = createClient(new Worker('worker.js'), { 
  requestTimeout: 1000 

More examples

Simple API for sending work to your web worker (recommended).

See examples/simple-send-work-to-webworker

Standard API for sending work to your web worker.

See examples/send-work-to-webworker

Bidirectional connection

Each side works as client and server the same time.

See examples/bidirectional-calls

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npm i mole-rpc-transport-webworker

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  • koorchik