Node.js

Question 1

What is Node.js?

Answer 1

built on chrome’s JavaScript runtime for building fast and scalable network applications. uses event-driven non-blocking I/O model. JavaScript without the browser

Question 2

What can Node.js be used for?

Answer 2

you can do anything with networking with it, though not suggested for 3d graphics, can only be back-end

Question 3

What is a REPL?

Answer 3

read-eval-print loop, interactive toplevel or language shell. Takes single user inputs, executers them, and returns the result to the user, and is executed piecewise. Ex. console

Question 4

When was Node.js created?

Answer 4

May 27, 2009

Question 5

What back end languages have you heard of?

Answer 5

ruby, python, php, sql (a database for languages), java, JavaScript

Question 6

What is a computer process?

Answer 6

a process contains a program code and its activity, it is executers in one or many threads.

Question 7

Roughly how many computer processes are running on your host operating system (Task Manager or Activity Monitor)?

Answer 7

Currently I have 226

Question 8

Why should a full stack Web Developer know that computer processes exist?

Answer 8

A full stack web developer helps make multiple processes work together to form one application, so knowing about computer processes is important, especially since we’re using clients, servers, and databases

Question 9

How do you access the process object in the Node.js program?

Answer 9

node and the node command process, cause it’s global

Question 10

What is the data type of process.argv in Node.js?

Answer 10

array of strings

Question 11

What is a JavaScript module?

Answer 11

a file containing related code, used to be called scripts

Question 12

What values are passed into a Node.js module’s local scope?

Answer 12

exports, module, __filename, __dirname, require

Question 13

Give two examples of truly global variables in a Node.js program.

Answer 13

None of them are truly global, but __filename, __dirname, exports, module, and require are global in the scope of modules

Question 14

Give two examples of truly global variables in a Node.js program.

Answer 14

None of them are truly global, but __filename, __dirname, exports, module, and require are global in the scope of modules. console & process are truly global

Question 15

What is the purpose of module.exports in a Node.js module?

Answer 15

export a file to another file

Question 16

How do you import functionality into a Node.js module from another Node.js module?

Answer 16

require function, require()

Question 17

What is the JavaScript Event Loop?

Answer 17

constant process of callstack being put back on the callstack queue

Question 18

What is different between “blocking” and “non-blocking” with respect to how code is executed?

Answer 18

non-blocking is when the queue is cleared and can continue, blocking is when something is on the callstack

Question 19

What is directory?

Answer 19

a folder, a collection of files created for a purpose

Question 20

What is a relative file path?

Answer 20

location that is relative to a current directory

Question 21

What is an absolute file path?

Answer 21

contains the root element and the complete directory list required to locate a file

Question 22

What module does Node.js include for manipulating the file system?

Answer 22

fs (file system) module

Question 23

What method is available in Node.js fs module for writing data to a file?

Answer 23

writeFile method

Question 24

What is a client?

Answer 24

wants data

Question 25

What is a server?

Answer 25

gives data

Question 26

Which HTTP method does a browser issue to a web server when you visit a URL?

Answer 26

GET

Question 27

What is the first line of an HTTP request message?

Answer 27

method, request target, target

Question 28

What is on the first line of an HTTP response message?

Answer 28

http version number, status code, reason phrase

Question 29

What are HTTP headers?

Answer 29

additional information of key value pairs to give. let client and the server pass additional information with an http request or response

Question 30

Is a body required for a valid HTTP message?

Answer 30

No, Get for without body, Post for with body

Question 31

What is NPM?

Answer 31

package manager (website, registry, command line)

Question 32

What is a package?

Answer 32

packages is a directory with one or more files in them, including package.json

Question 33

How can you create a package.json with npm?

Answer 33

cd /path/to/package , npm init –yes

Question 34

What is a dependency and how do you add one to a package?

Answer 34

npm install , packages required by your application in production.

Question 35

What happens when you add a dependency to a package with npm?

Answer 35

npm will download dependencies and devDependencies that are listed in package. json that meet the semantic version requirements listed for each.