Node/Express Pocket Map

The Glovebox Reference

Driving at 100mph doesn’t leave much time to read documentation. Keep this map in your glovebox.

Fig 1: Your Guide to the Node.js Galaxy (and Express).

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Quick-Start Ignition

const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;

app.listen(PORT, () => console.log(`Driving on ${PORT}`));

Routing & Traffic

Method	Syntax	Use Case
GET	app.get('/path', handler)	Read/Retrieve
POST	app.post('/path', handler)	Create/Send
PUT	app.put('/path', handler)	Update (Replace)
DELETE	app.delete('/path', handler)	Destroy
Catch-All	app.all('*', handler)	404/Dead Ends

Accessing Data

• Route Params: /users/:id -> req.params.id
• Query Strings: /search?q=foo -> req.query.q
• Headers: req.get('Content-Type')

Responses (The Cargo)

• res.send("Text"): Quick text/HTML.
• res.json({ id: 1 }): API Data (Standard).
• res.sendFile("/abs/path/file.html"): Serve file.
• res.status(404): Set status code.

Middleware

// 1. Write it
const check = (req, res, next) => {
  if (ok) next();
  else res.status(403).send('No');
};

// 2. Use it (Global)
app.use(check);

// 3. Use it (Route)
app.get('/safe', check, handler);

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Extra Bits & Bytes

📘 Intro to Express.js Study Guide (PDF)

Express.js Github Repo

Express All In One Lifeline App - Demo Repo

⏭ Next Stop:

Rev up your templating engines.