چیت‌شیت Node.js

1import { readFile } from "node:fs/promises";23const text = await readFile("./notes.txt", "utf8");

1import { writeFile } from "node:fs/promises";23await writeFile("./output.txt", "Generated locally\n", {4  encoding: "utf8",5});

1import { join, resolve } from "node:path";23const configPath = join(process.cwd(), "config", "app.json");4const absolutePath = resolve(configPath);

1const port = Number(process.env.PORT ?? 3000);23if (!Number.isInteger(port) || port < 1 || port > 65535) {4  throw new Error("PORT must be a valid TCP port");5}

1import { createServer } from "node:http";23const server = createServer((request, response) => {4  response.writeHead(200, { "content-type": "text/plain; charset=utf-8" });5  response.end("Hello from Node.js");6});78server.listen(3000, "127.0.0.1");

1async function loadData() {2  try {3    const response = await fetch("https://example.com/data");4    if (!response.ok) throw new Error(`HTTP ${response.status}`);5    return await response.json();6  } catch (error) {7    console.error("Unable to load data", error);8    throw error;9  }10}

1const timeout = setTimeout(() => {2  console.log("Timed out");3}, 1000);45clearTimeout(timeout);

1import { EventEmitter } from "node:events";23const events = new EventEmitter();4const onReady = () => console.log("ready");56events.once("ready", onReady);7events.emit("ready");

1import { createReadStream, createWriteStream } from "node:fs";2import { pipeline } from "node:stream/promises";34await pipeline(5  createReadStream("input.log"),6  createWriteStream("archive.log"),7);

1import test from "node:test";2import assert from "node:assert/strict";34test("adds two values", () => {5  assert.equal(2 + 3, 5);6});