'use strict'; const fs = require('fs'); const crypto = require('crypto'); const {parentPort} = require('worker_threads'); const handlers = { hashFile: (algorithm, filePath) => new Promise((resolve, reject) => { const hasher = crypto.createHash(algorithm); fs.createReadStream(filePath) // TODO: Use `Stream.pipeline` when targeting Node.js 12. .on('error', reject) .pipe(hasher) .on('error', reject) .on('finish', () => { const {buffer} = hasher.read(); resolve({value: buffer, transferList: [buffer]}); }); }), hash: async (algorithm, input) => { const hasher = crypto.createHash(algorithm); if (Array.isArray(input)) { for (const part of input) { hasher.update(part); } } else { hasher.update(input); } const hash = hasher.digest().buffer; return {value: hash, transferList: [hash]}; } }; parentPort.on('message', async message => { try { const {method, args} = message; const handler = handlers[method]; if (handler === undefined) { throw new Error(`Unknown method '${method}'`); } const {value, transferList} = await handler(...args); parentPort.postMessage({id: message.id, value}, transferList); } catch (error) { const newError = {message: error.message, stack: error.stack}; for (const [key, value] of Object.entries(error)) { if (typeof value !== 'object') { newError[key] = value; } } parentPort.postMessage({id: message.id, error: newError}); } });