Lecture 9

Question 1

what is DNS? (2)

Answer 1

1 domain name server

2 the process through which human-readable domain names (www.digicert.com) are translated into a computer-readable IP address (216.168. 246.55)

Question 2

Explain the request response cycle

Answer 2

1. computer makes a request from the server
2. server processes the request
3. server issues a response

Question 3

Response status codes (4)

Answer 3

2xx - Success
3xx - Redirect (example we get directed to google.com without a www)
4xx - Client Error (your fault!)
5xx - Server Error (not your fault!)

Question 4

what are GET and POST requests

Answer 4

GET is used to request data from a specified resource

POST request - Useful for writing data

Question 5

what is a post request? + example

Answer 5

POST requests can transmit data of any type

Example of POST response is posting a photo on facebook.

Question 6

API

(4)

Answer 6

1 Application programming interface
2 Allows you to get data from another application without needing to understand how the application works
3 Can often send data back in different formats
4 Examples of companies with APIs: GitHub, Spotify, Google

Question 7

request module + syntax

Answer 7

allows you to send HTTP requests in Python

!pip install requests

Question 8

requests get method (3) + syntax

Answer 8

1 retrieves information from the server using a given URL. The GET method sends the encoded user information appended to the page request.

2 The page and the encoded information are separated by the ‘?’ character.

3 not suitable for sending sensitive information

requests.get(url, params={key: value}, args)

Question 9

ok method + syntax

Answer 9

returns True if status_code is less than 400, otherwise False

x.ok

where x is a variable containing a get request eg

x=requests.get(url)

Question 10

.text method

Answer 10

returns the content of the response, in unicode. Basically, it refers to Binary Response content. (???)

Question 11

headers ()

Answer 11

1 HTTP headers let the server know additional information about the reqeuest

2 All the headers are NOT case-sensitive

3 headers fields are separated by colon, key-value pairs.

ex: Headers = { “Authorization” : ”our_unique_secret_token” }

Question 12

.status_code method

Answer 12

returns status code of a get request

Question 13

what does the headers argument do in the response module?

Answer 13

import requests
url = “https://icanhazdadjoke.com/search”
response = requests.get(url, headers={‘Accept’:’text/plain’})
print(response.text)

headers={‘Accept’:’text/plain’} This argument returns a plain text version.

Question 14

JSON (2)

Answer 14

1 stands for JavaScript Object Notation.

2 Python can convert it very quickly to a valid python code.

Question 15

why do we want json. in dictionary form and how do we do it?

Answer 15

prints the JSON data in the Python dictionary format as seen in the output.

In this way, we can parse JSON responses in Python. and access them via dictionary format.

syntax: x.json()

where x is a variable storing a get request

Question 16

What’s a Query String?

Answer 16

1 A way to pass data to the server as part of a GET request

2 A query string is a set of characters tacked onto the end of a URL.

3 The query string begins after the question mark (?) and can include one or more parameters. Each parameter is represented by a unique key-value pair or a set of two linked data items. An equals sign (=) separates each key and value. An ampersand (&) separates multiple parameters.

Question 17

define endpoint

Answer 17

endpoint is a specific location within an API that accepts requests and sends back response

Question 18

what is unicode?

Answer 18

(eg the Unicode Standard) is a universal text encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world’s writing systems that can be digitized

Question 19

what is a payload?

Answer 19

a data package that is sent between a client and server in a web API.