express

Question 1

What is Express useful for?

Question 2

How does Express fit into a full-stack web application?

Question 3

How do you add express to your package dependencies?

Answer 3

npm install express

Question 4

What Express application method starts the server and binds it to a network PORT?

Answer 4

the app.listen method and port is often used to identify specific services.

Question 5

What is Express middleware?

Question 6

What is Express middleware useful for?

Question 7

How do you mount a middleware with an Express application?

Question 8

Which objects does an Express application pass to your middleware to manage the request/response lifecycle of the server?

Question 9

What is an API endpoint?

Answer 9

what you send in the request path it’s everything after the colon

Question 10

What is the appropriate “Content-Type” header for HTTP messages that contain JSON in their bodies?

Question 11

What is the significance of an HTTP request’s method?

Answer 11

it tells you what you are doing with the information

Question 12

Is a server required to do a request?

Answer 12

NO, it’s all convention

Question 13

Where does express and node fit in the three tier architecture?

Answer 13

in the backend or server

Question 14

What does the function app.get do?

Answer 14

it checks if the path matches (or endpoint) and if so it runs the function app.use

Question 15

What does app.use mean?

Answer 15

it mounts a middleware function

Question 16

When does express run the middleware?

Answer 16

when the path runs through the network port

Question 17

What is the middleware?

Answer 17

app.use is a callback function or middleware they are the same thing

Question 18

If there are multiple middleware, do they all execute?

Answer 18

only if they call next( ) if not the chain ends. if there are no response it sends an error.

Question 19

What is the difference between app.use and app.get?

Answer 19

app.get is a structured call that uses app.use

Question 20

What is the difference between res.send, res.json and res.sendStatus?

Answer 20

res.send is the general one, res.json JSON stringifies the data and calls res. send to send out the data, and res.sendStatus sends the status code.

Question 21

What is the purpose of the Express Static middleware?

Question 22

What does express.static() return?

Answer 22

it returns a middleware function

Question 23

What are several examples of static files?

Answer 23

images, css files, html files, json files, basically anything where it treated like a read file

Question 24

What is a good way to serve application images using Express?

Answer 24

using express.static