Authentication - Basics

Basics Overview

At its core, basics is about doing one thing well inside your authentication project. Once you understand the pattern, you can apply it consistently across features and teams.

Good basics pays off across the whole codebase: fewer surprises, easier testing, and smoother onboarding. The snippet below is a solid starting point.

import express from 'express';
import jwt from 'jsonwebtoken';

const app = express();
app.use(express.json());

function authenticate(req, res, next) {
  const token = req.headers.authorization?.replace('Bearer ', '');
  try {
    req.user = jwt.verify(token, process.env.JWT_SECRET);
    next();
  } catch {
    res.status(401).json({ error: 'Unauthorized' });
  }
}

Authentication middleware verifies the caller's identity before protected handlers run.

Basics Example

// verify the caller on every protected request
function authenticate(req, res, next) {
  const token = req.headers.authorization?.replace('Bearer ', '');
  req.user = verifyToken(token); // throws if invalid
  next();
}

• Start from a minimal Basics example and grow it only as needed.
• Keep configuration explicit so Basics behaves the same in every environment.
• Name things clearly so teammates understand your Basics at a glance.
• Add tests around Basics early to lock in expected behaviour.

Authentication Cheatsheet

Quick authentication reference related to basics.

How Basics Works

Basics is part of proving who a user is and what they are allowed to do. Authentication verifies identity, while authorization decides access — and basics plays a specific role in that flow.

Authentication middleware verifies the caller's identity before protected handlers run.

• Never store or log plain-text passwords or secrets.
• Prefer short-lived tokens with refresh over long-lived ones.
• Always send credentials over HTTPS.
• Fail closed: deny access when anything is uncertain.

Security Guidance for Basics

Security is the whole point of basics. Small mistakes — weak hashing, tokens in localStorage, missing rate limits — are exactly what attackers look for, so follow proven defaults.

Common Mistakes

• Skipping error handling and edge cases when wiring up basics.
• Leaving basics untested, so regressions slip into production.
• Over-engineering basics before you actually need the extra flexibility.
• Ignoring documentation, which makes basics hard for the next developer to change.

Key Takeaways

• Basics is a core part of working effectively with authentication.
• Start small and keep basics focused on a single responsibility.
• Apply consistent patterns so basics scales across your project.
• Test and document basics to keep it maintainable over time.