Node Js Online Test

1. In Node.js, what is the purpose of the res object in an HTTP request handler function?

To store client requests To define the server's routing To represent the HTTP response that will be sent back to the client To read data from files

2. What HTTP methods are commonly used in RESTful APIs to perform CRUD (Create, Read, Update, Delete) operations on resources?

GET, POST, PUT, DELETE CREATE, FETCH, MODIFY, DELETE READ, WRITE, UPDATE, REMOVE REQUEST, RECEIVE, UPDATE, REMOVE

3. Which Node.js function is used to add a callback to the "next tick queue" for execution in the next iteration of the event loop?

setTimeout setImmediate process.nextTick setInterval

4. What is a "memory leak" in the context of Node.js performance?

A type of routing issue A situation where an application fails to release memory after it is no longer needed, leading to memory consumption growth A method for managing hardware devices A performance-enhancing feature of Node.js

5. In the context of Node.js performance, what is "caching"?

A method for managing hardware devices Storing frequently accessed data in memory to reduce redundant computations and speed up responses The process of creating static HTML templates A type of routing strategy

6. 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

7. Which Node.js testing library is commonly used for E2E testing of web applications?

Jest Puppeteer Chai Axios

8. Which tool is commonly used for memory profiling in Node.js applications?

Postman Chrome Developer Tools Apache JMeter Load Impact

9. In Node.js, how is the connection to a PostgreSQL database typically established using the pg module?

By calling the pg.connect() method By specifying the database connection details in a JavaScript file By using the pg.createConnection() method and passing connection options By defining a new PostgreSQL class

10. 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

11. Which Node.js module is commonly used for connecting to MongoDB databases?

mongo mysql mongodb mongoose

12. Which built-in debugging tool is available in Node.js for inspecting code execution and troubleshooting?

Chrome Developer Tools Visual Studio Code Node Inspector Jasmine

13. Which testing framework is commonly used for unit testing in Node.js?

Mocha Express Sequelize WebSocket

14. What is asynchronous programming in Node.js?

A programming style that uses only synchronous functions A programming style that avoids using functions altogether A programming style that allows non-blocking execution of tasks, often involving callbacks or promises A programming style that focuses on single-threaded execution

15. Which HTTP status code should be returned when a requested resource is not found in a Node.js web application?

200 OK 201 Created 404 Not Found 500 Internal Server Error

16. What is a key advantage of using streams in Node.js for I/O operations?

Streams are only suitable for handling small amounts of data. Streams automatically handle error handling and data validation. Streams allow data to be processed piece by piece, reducing memory consumption and improving performance. Streams can only be used for reading data, not writing data.

17. In Express.js, how is routing typically defined for handling HTTP requests?

Using the app.middleware method Using the app.route method Using the app.use method Using the app.process method

18. What is the primary advantage of using a RESTful API design in Node.js?

It uses a binary protocol for faster data transfer. It allows for real-time communication between the server and client. It provides a uniform and scalable approach to web service development, making it easy to consume data and interact with resources. It requires minimal server configuration.

19. What is the purpose of the WebSocket.on('message') event in Node.js WebSocket communication?

To log errors To close the WebSocket connection To handle incoming messages from the WebSocket clients To establish a secure connection

20. Which Node.js module is commonly used for connecting to MySQL databases?

mongo mysql postgresql mongoose