Utility Process API

import { createParentPortHandler } from 'electron-messageport-trpc/utility';

createParentPortHandler(opts)

Attaches a tRPC request handler to the utility process’s parentPort. This allows the main process (or, via brokering, a renderer) to call tRPC procedures running in a utility process.

Parameters

interface CreateParentPortHandlerOptions<TRouter extends AnyRouter> {
  router: TRouter;
  parentPort: ParentPort;
  createContext?: () => Promise<unknown>;
}

Parameter	Type	Required	Description
router	AnyRouter	Yes	Your tRPC router instance
parentPort	ParentPort	Yes	The utility process parent port from electron
createContext	() => Promise<unknown>	No	Factory function called for every request

Returns

A { handlers: PortHandler[] } object. Each transferred port creates one handler.

Example

utility-worker.ts

import { createParentPortHandler } from 'electron-messageport-trpc/utility';
import { initTRPC } from '@trpc/server';

const t = initTRPC.create();

const router = t.router({
  heavyComputation: t.procedure.query(async () => {
    // Runs in a separate thread, not blocking the main process
    return performExpensiveWork();
  }),
});

createParentPortHandler({
  router,
  parentPort: process.parentPort,
});

// main process
import { MessageChannelMain, utilityProcess } from 'electron';
import { createTRPCClient } from '@trpc/client';
import { mainPortLink } from 'electron-messageport-trpc/main';

const child = utilityProcess.fork('utility-worker.js');
const { port1, port2 } = new MessageChannelMain();

child.postMessage({ type: 'connect' }, [port1]);

const client = createTRPCClient({
  links: [mainPortLink({ port: port2 })],
});

Use Cases

• CPU-intensive computation without blocking the main process
• File processing in a background thread
• Database operations isolated from the main process
• Renderer-to-utility brokering when the main process should only hand off a port