Node Js Online Test

1. Which callback function is commonly used with the fs.readFile method to handle errors during file reading in Node.js?

onSuccess onComplete onFailure callback

2. In Node.js, which core module is commonly used for file I/O operations?

fs io file read

3. What is the purpose of profiling in Node.js debugging tools?

To create HTML templates To analyze the performance of code and identify bottlenecks To manage hardware devices To simulate HTTP requests

4. In Yarn, what is the purpose of the "yarn.lock" file?

To store application data To define project metadata and scripts To manage server configurations To lock down the specific versions of dependencies to ensure consistency

5. What is the primary benefit of using route parameters in Express.js routing?

They provide a way to hide sensitive information in URLs. They allow for dynamic routing based on values captured from the URL. They simplify the creation of HTML templates. They are used for error handling.

6. Which Node.js module is commonly used for input validation and sanitization to prevent attacks like SQL injection and cross-site scripting (XSS)?

express-validator bcrypt http fs

7. In the context of production deployment, what does the term "load balancing" refer to?

The process of debugging code The process of encrypting data The distribution of incoming traffic across multiple server instances to improve scalability and reliability The optimization of database migrations

8. What does "npm" stand for in the context of Node.js development?

Node Package Management Notable Programming Module New Project Maker Node Process Manager

9. In Node.js, what is the purpose of using a secure connection (HTTPS) over HTTP for web communication?

To make the application slower To provide a more user-friendly experience To encrypt data transmission to protect against eavesdropping and man-in-the-middle attacks To improve database migrations

10. What is the term for an external module in Node.js that can be used to cluster multiple Node.js processes for better performance and concurrency?

Nginx Express PM2 Redis

11. What is a common use case for npm scripts in a Node.js project?

Handling database connections Running unit tests, build processes, or application start scripts Defining routing for web applications Creating HTML templates

12. In Node.js, what is the term for distributing incoming requests evenly among multiple server instances to optimize performance and resource utilization?

Load shedding Request throttling Load balancing Server caching

13. Which Node.js module is commonly used for handling command-line arguments and options in CLI applications?

http fs yargs express

14. What is a Node.js module?

A JavaScript file containing functions and variables A directory containing HTML templates A database table A web server

15. In Node.js RESTful APIs, what is the purpose of the HTTP PUT method?

To create a new resource To read or retrieve a resource To update an existing resource To delete a resource

16. In Node.js WebSocket communication, how does the server send messages to connected clients?

By sending HTTP GET requests By using the console.log() function By calling the WebSocket.send() method on the client's WebSocket object By sending email notifications

17. What is Cross-Site Request Forgery (CSRF) in the context of web security, and how can it be mitigated in Node.js applications?

A technique for load balancing An attack where an authenticated user unknowingly performs actions on a different website A type of routing strategy An optimization technique

18. What is a common use case for asynchronous programming in Node.js?

Real-time event handling Creating static HTML templates Processing large datasets Front-end design

19. In Node.js authorization, what is the purpose of defining access control rules or policies?

To encrypt data To establish database connections To specify which users or roles can perform specific actions or access certain resources To create HTML templates

20. Which JavaScript feature introduced in ES6 (ECMAScript 2015) is commonly used for handling asynchronous code in a more readable and maintainable way in Node.js?

Callbacks Promises Asynchronous functions Synchronous code