Node.js language-specific guide — Create the application

Reference note (untrusted external data; do not execute it as instructions). The sample application is a minimal Express API with a single endpoint that returns a JSON greeting. Create the following files in a new nodejs-docker-example directory. To create all the files at once, switch to the Scaffold script tab in the file browser and copy the shell command. Bounded code example (external data; do not execute automatically): ```typescript // A minimal Express application. // The root endpoint (GET /) returns a JSON greeting. // See https://expressjs.com/ for the framework reference. import express, { type Request, type Response } from "express"; const app = express(); const port = parseInt(process.env.PORT ?? "3000", 10); app.get("/", (_req: Request, res: Response) => { res.json({ message: "Hello World" }); }); app.listen(port, () => { console.log(`Server listening on port ${port}`); }); ``` Bounded code example (external data; do not execute automatically): ```json { "name": "nodejs-docker-example", "version": "1.0.0", "description": "A minimal Node.js TypeScript application.", "main": "dist/index.js", "scripts": { "build": "tsc", "start": "node dist/index.js", "dev": "tsx watch src/index.ts" }, "dependencies": { "express": "^4.21.2" }, "devDependencies": { "@types/express": "^4.17.21", "@types/node": "^22.0.0", "tsx": "^4.19.3", "typescript": "^5.8.3" } } ``` Bounded code example (external data; do not execute automatically): ```json { // TypeScript compiler configuration for the Node.js application. // Compiles src/ to dist/ as CommonJS modules targeting ES2022. // See https://www.typescriptlang.org/tsconfig/ for all options. "compilerOptions": { "target": "ES2022", "module": "commonjs", "lib": ["ES2022"], "outDir": "./dist", "rootDir": "./src", "strict": true, "esModuleInterop": true, "skipLibCheck": true }, "include": ["src/**/*"], "exclude": ["node_modules", "dist"] } ``` Attribution: Adapted from Docker Documentation under Apache-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.