Express application structure - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main purpose of the app.js file in an Express application?

The app.js file sets up the Express app, configures middleware, routes, and error handling. It is the central place where the app is created and configured.

beginner

Why do Express apps often have a routes folder?

The routes folder organizes route handlers by grouping related URL paths and their logic. This keeps the code clean and easier to maintain.

intermediate

What is the role of middleware in Express application structure?

Middleware functions run during the request-response cycle. They can modify requests, responses, or end the cycle. Middleware helps add features like logging, parsing, and authentication.

beginner

How does the public folder fit into an Express app structure?

The public folder holds static files like images, CSS, and JavaScript that the browser can access directly. Express serves these files using built-in middleware.

beginner

What is the purpose of the views folder in an Express app?

The views folder contains template files that generate HTML dynamically. These templates are rendered by the app to send web pages to users.

Which file usually starts the Express server?

A server.js

B app.js

C routes.js

D index.html

The server.js file typically imports the app and starts the server listening on a port.

Where should you put your route definitions in an Express app?

A In the <code>node_modules</code> folder

B In the <code>public</code> folder

C In the <code>views</code> folder

D In the <code>routes</code> folder

Routes are organized in the routes folder to keep the app structure clean.

What does middleware do in Express?

A Handles HTTP requests and responses

B Stores static files

C Creates HTML templates

D Manages database connections

Middleware functions process requests and responses during the app's request-response cycle.

Which folder contains static assets like images and CSS?

A views

B routes

C public

D config

The public folder holds static files served directly to the browser.

What is the purpose of the views folder?

A To store route handlers

B To store template files for rendering HTML

C To store static files

D To store middleware functions

The views folder contains templates that generate HTML pages dynamically.

Describe the typical folder structure of an Express application and the role of each main folder.

Think about where you put code for routes, templates, and static files.

Explain how middleware fits into the Express application structure and why it is important.

Middleware is like helpers that run between receiving a request and sending a response.