Web/Apps 2018

Node.js is best used for:

CPU intensive applications

Scalable network applications

Relational database applications

All of the above

According to the NodeSource article, what problem arises from "long polling"?

Latency

Increases server load

Needs to work synchronously

We register the event handlers in a React client in the life cycle method componentWillMount

True

False

In addition to Node's http server what else are we hooking socket.io into the server

Error middleware

Builtin middleware

Dotenv

Express

Refreshing the browser causes a disconnect to fine the server

True

False

If you're going to handle databases with Node.js, what other software should you include?

Message queing

REST infastructure

Caching

Text messaging

If we want to send a message to all clients in a room, we could use this syntax on the server: io.to('someroom').emit('somemessahe',..

True

False

What syntax do we provide in app.js to contain all subsequent socket.io event emitters and handlers?

Let io = socketIO(server)

Io.on('connection', (socket) => {..

Var socket = io()

Let server = http.createServer(app)

After a connection was established, what event did the client first fire?

Request

Respond

Join

Welcome

What package(s) were installed to support socket IO?

Socket.io-server

Socket.io-client

Socket.io

Which type of applications should you use a traditional web server like ASP.Net MVC for?

How many connection can a typical web server handle?

400

4000

1 million

2000

How many connections can a node.js server handle?

1 million

4000

2 million

200

Describe how socket.io works in conjunction with an http server

It just "attaches" to the server as middleware

It acts as the http server

It calls the server as a client

In addition to the http server what framework are we hooking socket.io into?

Express

Node.js

Socket.io-server

AJAX

On the client, what is the “global socket variable” known as?

EventHandler

EventEmitter

.env

Event

What method is used on both the client and the server to invoke an event?

Attach

Emit

Connect

What is the npm package name for the socket io version we’re using?

Socket.io

Socket

What is Heroku?

A cloud platform that lets companies build, deliver, monitor and scale apps

A command line tool for Git

A package manager

What git command is used to create a new archive?

Git init

Git status

Git add .

Git commit

What git command tells us what files need to be added to the archive?

Git init

Git status

Git add .

Git commit

What git command will add all files to the archive?

Git init

Git status

Git add .

Git commit

What git command will finalize the adding of files to the archive?

Git init

Git status

Git add .

Git commit

What adjustments are required before we port our app to Heroku?

What does SSH Keys stand for?

Secure Shell Keys

Super Slippery Honey Keys

Secure Secret Host Keys

What is the purpose of an ssh key?

Ensures that unauthorized users cannot place files in our Heroku

Ensures that your app is public on Heroku

Ensures that unauthorized users can't see your new app

What time zone does Heroku us by default?

EST

GMT

MDT

MGMT

What Heroku command do we use to change the time zone?

Heroku config:add TZ="America/Detroit" --app yourname-appname

Heroku config:add TZ="America/Detroit" --time xxxxxx-traficlights

Git config:add TZ="America/Detroit" --app xxxxxx-traficlights

What does the floor method do?

Rounds a number up to the nearest integer

Rounds a number down to its nearest integer

How would you return a random number between 1 and 10?

Math.random((Math.floor() * 10) + 1)

Math.floor((Math.random() * 10) + 1)

Math.floor((Math.random())

Math.floor((Math.random() * 10)

How do we render random colors in our casestudy?

Very carefully

Using the math functions to generate a random index of a color in a json file

Using the math functions to generate 6 random chars and append them to be a random hex value

Using the random color function

How would you use format the current time as 4:47:39 pm?

Moment().format('h:mm:ss a')

Now().format('h:mm:ss a')

Moment().now().format(hour minute second)

Moment().format('h.m.s.a')

What syntax is used by the client to establish a connection to a server in socket.io?

Const socket = io.connect();

Io.on('connection', (socket) =>

This.state.socket.emit('connection',

Socket.on('connection', this.connection);

What syntax is used by the server to handle the connection of a client?

Const socket = io.connect();

Io.on('connection', (socket) =>

This.state.socket.emit('connection',

Socket.on('connection', this.connection);

What syntax is used on the server to join a particular room?

Socket.join(clientData.roomName);

Socket.on('join', (clientData) =>

Io.on('join', (socket) =>

What syntax is used on the server to send a message to a single user?

Io.to(socket.id).emit('welcome', msg) ;

Socket.broadcast.to(clientData).emit('welcome', msg);

Io.emit('currentusers', userinfo )

What syntax is used on the server to send a message to all users in the room?

Io.to(socket.id).emit('room', msg) ;

Socket.broadcast.to(clientData.roomName).emit('joined', msg);

Io.emit('currentusers', userinfo )

What syntax is used on the server to send a message to all users in all rooms?

Io.to(socket.id).emit('newMsg', msg) ;

Socket.broadcast.to(clientData.roomName).emit('joined', msg);

Io.emit('currentusers', userinfo )

What React lifecycle method is used to register event handlers for socket.io server generated messages?

ComponentDidMount

Constructor

Connect

What syntax is used in the method to register a method for a server generated ‘welcome’?

Socket.io('welcome', this.onWelcome);

Socket.on( this.onWelcome, 'welcome');

Socket.io(this.onWelcome, 'welcome');

Socket.on('welcome', this.onWelcome);

What does CORS stand for?

Control Origin Region System

Cross-Origin Resourcing Sharing

Code Optimization Resource Sharing

What three headers do we have to set to fix CORS errors?

How did we distinguish between individual

Key attribute

User attribute

ViewDialog attribute

Users attribute

How was the individual user's data made available in the

Key attribute

User attribute

ViewDialog attribute

Users attribute

How does the

Key attribute

User attribute

ViewDialog attribute

Users attribute

What does this line of .css code do: height: calc(80vh - 70px);

Calc is how you do math in css

80vh divides the current viewport and use 80/100 of it regardless of what device we're on

80 px past the center - 70 px

Only sets the height for vh devices

What does PWA stand for?

Public Web App

Peng Wan App sun

Progressive Windows App

Progressive Web App

What is the purpose of the web manifest?

to install web applications to the homescreen of a device

To please evan laureson

A package file

What is a service worker?

AppCache

A server slave

Business speak for a web developer

A script that your browser runs in the background, separate from a web page

What are we using our service worker for?

To boost our PWA score

To create a custom offline page

To manage the server

Performance

Unlock and Upgrade

Remove all limits from your Quizzes

Web/Apps 2018

More Quizzes