comlink-stdio

comlink-stdio

• TypeDoc Documentation
• JSR Documentation

This project is a stdio version of comlink. Making it easier to do IPC between TypeScript processes using RPC style API calls.

Regular js/ts files can directly import/require each other as libraries, this package isn't designed for these normal use cases, but designed for special scenarios where 2 JS processes are not in the same environment. e.g. I am running main process with Tauri in a web brower, it needs to run a Deno process (which has more acess to the OS resources), in this scenario both sides are js/ts but they can't import each other as libraries. Instead of starting an http server using Deno/Node/Bun, stdio is more lightweight. However, stdio's argv, stdin, stdout is too low level, implementing API calls with them requires CLI-style programming, which is very inconvenient. comlink-stdio mimics comlink style API, making RPC-style API calls over stdio very easy.

This package is a completly TypeScript project, no JS bundle will be generated. If you write JS, you lose the main benefit of this package, which is RPC with type auto-complete.

Support

• Node.JS
• Deno
• Bun

Usage

See examples,

bun examples/parent.ts

parent.ts, run bun examples/parent.ts

import { RPCChannel } from "../src/bidirectional.ts";
import { apiMethods, type API } from "../src/api.ts";
import { spawn } from "child_process";
import { NodeStdio } from "../src/stdio/index.ts";

const worker = spawn("deno", ["examples/deno-child.ts"]);
// or
const worker = spawn("bun", ["examples/node-child.ts"]);
worker.stderr.pipe(process.stdout);

const stdio = new NodeStdio(worker.stdout, worker.stdin);
const parent = new RPCChannel<{}, API>(stdio, {});
const api = parent.getApi();

await api.add(1, 2).then(console.log); // 3
await api.subtract(1, 2).then(console.log); // -1
worker.kill();

examples/node-child.ts

import { RPCChannel } from "../src/bidirectional.ts";
import { apiMethods } from "./api.ts";
import { DenoStdio, NodeStdio } from "../src/stdio/index.ts";

const stdio = new NodeStdio(process.stdin, process.stdout);
const child = new RPCChannel(stdio, apiMethods);

examples/deno-child.ts

import { RPCChannel } from "../src/bidirectional.ts";
import { apiMethods } from "./api.ts";
import { DenoStdio, NodeStdio } from "../src/stdio/index.ts";

const stdio = new DenoStdio(Deno.stdin.readable, Deno.stdout.writable);
const child = new RPCChannel(stdio, apiMethods);

RPCChannel is a bidirectional IPC channel, it can send and receive messages between processes. JavaScript proxy is used to forward API calls over stdio. You just need to pass an API interface to RPCChannel as generic, then you get full auto-complete and type safety.

Since RPCChannel is a bidirectional channel, both process can serve as API server, and they can call each other's API.