Challenging Node Js Test - 78+ MCQs: Node.js test: Evaluate Your Expertise with Node.js Questions and Answers

1. Explain the concept of 'callback hell' and how it can be mitigated in Node.js.

It is the simultaneous execution of multiple callbacks, and it can be mitigated by using asynchronous functions.

It is the nesting of callbacks, and it can be addressed by using promises or async/await.

It refers to a bug in the event loop, and it can be resolved by updating Node.js to the latest version.

It is the absence of callback functions, and it can be resolved by enabling strict mode.

2. What is the purpose of the 'os' module in Node.js?

To manage operating system processes in a Node.js application.

To optimize system performance through resource allocation.

To create custom operating systems using Node.js.

To gather information about the operating system environment.

3. Discuss the role of the 'jsonwebtoken' library in authentication for Node.js applications.

It is used for encrypting and decrypting database passwords.

It facilitates secure file uploads and downloads.

It is crucial for implementing OAuth 2.0.

It enables the creation and verification of JSON Web Tokens for user authentication.

4. How does Node.js handle unhandled exceptions in applications?

By automatically restarting the application.

By logging the exception and continuing with normal execution.

By crashing the application to prevent further damage.

By notifying the developer through email alerts.

5. What is the purpose of the 'querystring' module in Node.js?

To handle database queries in an Express.js application.

To parse and stringify URL query strings.

To create dynamic queries in a Node.js application.

To manage query parameters in HTTP requests.

6. How can you terminate a Node.js process?

Ctrl + C

Ctrl + Z

End Process command

Terminate() function

7. What is the purpose of the 'stream' module in Node.js?

Streaming media content

Handling file streams

Streamlining database queries

Managing network streams

8. Explain the concept of 'npm scripts' and their significance in Node.js projects.

npm scripts are used for installing Node.js packages globally.

npm scripts define custom commands for various project tasks, enhancing automation and consistency.

npm scripts are solely for managing project documentation.

npm scripts are deprecated, and developers are encouraged to use alternative tools.

9. What is the purpose of the 'async' and 'await' keywords in Node.js?

To manage asynchronous operations using callbacks.

To define asynchronous functions.

To handle exceptions in asynchronous code.

To simplify asynchronous code and make it more readable and maintainable.

10. How does error handling differ in synchronous and asynchronous code in Node.js?

In synchronous code, errors are typically handled using try-catch blocks, while in asynchronous code, errors are handled using callbacks or promises.

Error handling is the same in both synchronous and asynchronous code.

In synchronous code, errors are automatically caught by the event loop, while in asynchronous code, developers need to manually catch errors.

Error handling is not supported in Node.js applications.

11. How can you handle file uploads in an Express.js application?

By using the 'express-upload' middleware.

By including the 'multipart/form-data' content type in the form.

By manually parsing the request body in the route handler.

All of the above.

12. What is the purpose of the 'fs' module in Node.js?

Handling file system operations

Managing front-end styles

Facilitating server communication

Filtering scripts

13. In Node.js, how can you include external modules in your code?

Using import statement

Using require statement

Using include statement

Using module statement

14. Discuss the role of the 'Cluster' module in Node.js and its benefits.

It manages multiple Node.js applications simultaneously.

It enables parallel processing of tasks within a single Node.js instance.

It handles clustering of servers for improved performance and reliability.

It provides a visual representation of the application's performance.

15. How can you handle errors in asynchronous functions in Node.js?

Using try-catch blocks

Using error callbacks

Using error events

Errors cannot be handled in asynchronous functions

16. How can you handle asynchronous operations in Node.js?

Using callbacks

Using promises

Using async/await

All of the above

17. Which Node.js method is used to read environment variables?

process.env()

readEnv()

getEnv()

envRead()

18. What is the purpose of the 'Buffer' class in Node.js?

To handle file uploads in an Express.js application.

To store binary data directly in memory.

To manage database queries.

To control the flow of data in a stream.

19. What is the 'process.argv' property in Node.js?

It is used to access environment variables in a Node.js application.

It contains an array of command-line arguments passed to the Node.js process.

It represents the global object in Node.js.

It is a shorthand for 'argument vector' and is used to pass arguments to functions.

20. Which event is emitted when a new client connects to a Node.js server?

client.connect

server.connection

http.request

net.connection

21. Which module is commonly used for logging in Node.js applications?

log4js

console

debug

logging

22. What is the role of the 'events' module in Node.js?

Managing server events

Handling user interactions

Generating random events

Creating event-driven applications

23. Which command is used to install dependencies specified in 'package.json' in Node.js?

npm install

node install

npm dependencies

install package

24. Explain the concept of middleware chaining in Express.js.

It refers to connecting multiple Express.js applications to form a chain of middleware functions.

It involves linking multiple middleware functions together in a specific order to process incoming requests.

It is a technique for chaining multiple routes in an Express.js application.

Middleware chaining is not applicable in Express.js.

25. What is the event-driven architecture in Node.js?

A pattern for handling synchronous tasks

A design pattern for data storage

A way to handle multiple user inputs

A system where events trigger callbacks

26. How can you include external modules in Node.js?

Using the import statement

Through the require function

With the include directive

By importing from the global namespace

27. What is the significance of the 'Promisify' utility in Node.js development?

It converts synchronous functions into asynchronous ones.

It is used for creating promises in JavaScript.

It is part of the 'util' module for handling utilities.

It simplifies error handling in asynchronous code.

28. Which HTTP method is used for updating a resource in a Node.js RESTful API?

GET

POST

PUT

DELETE

29. What is the 'require' function in Node.js used for?

To import external modules and make them available in the current module.

To define new functions within a module.

To create a new instance of a class.

To include CSS styles in a Node.js application.

30. What does REPL stand for in the context of Node.js?

Read-Eval-Print Loop

Realtime Execution Programming Language

Repeating Event Processing Loop

Remote Environment Programming Language

31. What is the purpose of the 'vm' module in Node.js?

To handle virtual memory in a Node.js application.

To create and run scripts in isolated environments.

To manage view models in an Express.js application.

To validate modules before importing them.

32. How can you perform unit testing in a Node.js application?

By using the 'assert' module that comes with Node.js.

By employing third-party testing frameworks such as 'Mocha' or 'Jest'.

By creating custom testing functions within the application.

All of the above.

33. Differentiate between 'process.nextTick()' and 'setImmediate()' in Node.js.

'process.nextTick()' executes callback functions in the current event loop cycle, while 'setImmediate()' executes them in the next cycle.

'setImmediate()' is used for file system operations, whereas 'process.nextTick()' is for network-related tasks.

'setImmediate()' is deprecated in Node.js, and 'process.nextTick()' is the recommended alternative.

'process.nextTick()' is asynchronous, and 'setImmediate()' is synchronous.

34. What is the purpose of the 'express' module in Node.js?

Database management

Web application framework

Data encryption

User authentication

35. What is the purpose of the 'npm audit' command in Node.js development?

To install audit-related packages.

To analyze and report on project dependencies for known security vulnerabilities.

To create an audit trail for code changes.

To execute unit tests for the entire project.

36. How does the 'EventEmitter' class contribute to event handling in Node.js?

It is used for error handling in asynchronous operations.

It facilitates communication between parent and child processes.

It provides a mechanism for emitting and listening to events.

It manages file system events exclusively.

37. What is the purpose of the 'cluster' module in Node.js?

Creating clustered network architecture

Handling network requests

Managing server clusters

Cluster analysis of data

38. Explain the concept of 'streaming' in Node.js and its applications.

Streaming refers to playing audio and video files in a web browser.

It is the process of continuously transferring data in chunks, enhancing efficiency and reducing memory usage.

Streaming is applicable only to file system operations.

It is the mechanism for handling user authentication in real-time.

39. Examine the purpose of the 'module.exports' object in Node.js.

To export functions and variables from a module

To import modules in the global scope

To manage asynchronous operations

To execute code in a child process

40. In the context of Node.js, what is the purpose of the 'middleware'?

To execute code after the response has been sent.

To handle routing in the application.

To process data before reaching the route handler.

To manage database connections.

Node.js MCQ Test 2