Top built in modules

Question 1

What are the top 5 built in modules commonly used in node projects?

Answer 1

1. fs
2. path
3. os
4. events
5. http

Question 2

Explain the role of the fs module and name some functions of it.

Answer 2

Provides a set of methods to interact with the file system.

readFile()
writeFile()
appendFile()
unlink()
readdir()
mkdir()
rmdir()

Question 3

Explain the role of the path module and name some functions of it.

Answer 3

Provides utilities for joining, resolving, parsing, formatting, normalizing and manipulating paths.

join()
parse()
resolve()
extname()
dirname()

Question 4

Explain the role of the os module and name some functions of it.

Answer 4

Provides a set of methods for interacting with the operating system.

type()
userInfo()
totalmem()
freemem()

Question 5

Explain the role of the events module. Explain how to handle events in Node?

Answer 5

Used to handle events.

EventEmitter class of events module is used to register listeners and emit events.

Event listener is a function that will be executed when a particular event occurs.

on() method is used to register event listeners.

Question 6

What are Event Arguments?

Answer 6

When we emit an event we can pass additional information in the form of parameters/arguments.

myEmitter.emit(“event”, “argument1”, “argument2”);

Question 7

What is the difference between a function and an event?

Answer 7

Events represent an action and functions performr a specific task.

Events will call functions internally.

Question 8

What is the role of the http module in Node?

Answer 8

HTTP server for processing HTTP requests and responses.

The http module creates a server that listens on a port for requests and gives responses back to the client.

Question 9

What is the role of the createServer() method in the http module?

Answer 9

Creates an HTTP server.