Sanitization methods in Express - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of sanitization methods in Express?

Sanitization methods clean user input to remove harmful or unwanted characters, helping prevent security issues like injection attacks.

beginner

Name a popular Express middleware used for sanitizing input data.

express-validator is a popular middleware that provides sanitization and validation methods for Express applications.

beginner

How does the .trim() sanitization method work in express-validator?

The .trim() method removes whitespace from both ends of a string, making input cleaner and more consistent.

intermediate

What does the .escape() sanitization method do?

The .escape() method replaces HTML special characters like <, >, &, ' and " with their safe encoded equivalents to prevent HTML injection.

intermediate

Why should you use sanitization methods along with validation in Express apps?

Validation checks if input meets rules (like length or format), while sanitization cleans the input to remove harmful parts. Using both keeps data safe and reliable.

Which Express middleware is commonly used for sanitizing user input?

A morgan

B body-parser

C cors

D express-validator

express-validator provides both validation and sanitization methods for Express apps.

What does the .trim() method do in sanitization?

A Removes whitespace from both ends of a string

B Converts string to lowercase

C Removes all numbers from a string

D Encodes HTML entities

.trim() removes spaces or tabs from the start and end of the input string.

Why is .escape() important in sanitization?

A It removes all punctuation

B It prevents HTML injection by encoding special characters

C It converts strings to uppercase

D It validates email format

.escape() replaces characters like < and > with safe codes to avoid HTML injection.

Which of these is NOT a sanitization method in express-validator?

A .isEmail()

B .toInt()

C .normalizeEmail()

D .trim()

.isEmail() is a validation method, not sanitization.

What is the main goal of sanitization in Express apps?

A To style the webpage

B To speed up server response

C To clean input data and remove harmful characters

D To store data in a database

Sanitization cleans input to keep the app safe from attacks and errors.

Explain how sanitization methods help keep an Express app secure.

Think about how bad input can cause problems and how cleaning it helps.

List and describe three common sanitization methods used in express-validator.

Focus on methods that clean strings and make input safe.