What is the main advantage of using asynchronous programming in Node.js?

• Limited scalability

• Synchronous execution

• Non-blocking I/O operations

• Increased complexity

Explain the concept of RESTful APIs in one sentence.

• A set of rules and constraints for communication between systems over HTTP.

• A protocol for transferring files between systems

• A programming language used to build APIs

• A method for securing APIs using encryption keys

How can you handle errors in Node.js applications?

• Implement try-catch blocks, promises with .catch(), event emitters, and error middleware in Express.js

• Ignore errors and hope for the best

• Manually restart the server every time an error occurs

• Use Python instead of Node.js

Name one security best practice when working with Node.js applications.

• Ignore security vulnerabilities

• Implement input validation

• Use outdated libraries

• Disable logging

What is the role of the 'next' function in middleware?

• To terminate the middleware chain

• To return an error message

• To skip the current middleware function

• To pass control to the next middleware function in the stack.

How can you prevent SQL injection attacks in Node.js applications?

• Use parameterized queries with prepared statements, input validation, and sanitize user inputs.

• Trust all user inputs without any sanitization

• Ignore input validation and directly execute user inputs

• Use plain text queries without any validation

What is the purpose of the 'body-parser' middleware in Node.js?

• It sends the request body to a remote server

• It parses the incoming request body and makes it available under req.body property.

• It encrypts the request body for security purposes

• It generates random data for the request body

How can you securely store sensitive information such as API keys in Node.js applications?

• Use environment variables and dotenv package

• Use a plain text file to store API keys

• Save API keys in a public GitHub repository

• Store API keys directly in code

What is the significance of the 'req' and 'res' objects in middleware functions?

• The 'req' object is used for database queries

• The 'req' object represents the server's response

• The 'res' object represents the HTTP request

• The 'req' object represents the HTTP request and the 'res' object represents the HTTP response.

What is the purpose of using 'helmet' middleware in Node.js applications?

• To enhance security by setting various HTTP headers to protect against web vulnerabilities.

• To improve performance by caching static assets

• To handle user authentication and authorization

• To automatically generate API documentation