Skip to main content

Don't Stop 'Til You Get

 Don't Stop 'Til You Get

Today, we're going to learn about an alternative way of getting data from forms to the webserver.


So far, we've used post, which (kinda) packages up all the data from the form and sends it to the server.


We can think of this as the form controlling when the data is sent.


With the get method, the request for the data comes from the webserver. It effectively says gimme that data to the form.


You've probably seen get in use before. If you've ever seen a URL with a ? after the website name, then a bunch of = and maybe & symbols, then that website is using get.


So What's The Difference?

I'm glad you asked!


With post, the data in the form can't be seen by your web browser. Once it's sent, it's gone. This means that you can't bookmark or share a URL based on post data because it will be different for each user. Ever tried to drop those SO subtle present hints by sharing a shopping cart link? Only to get a link that doesn't show any shopping cart? Yep, that's the problem with post. The link for you will be different than the one for other users.


Get data encodes the data in the URL so we can bookmark & share it and get the same results from the page.


👉 Let's add some code to our Flask boilerplate to show how this works.


from flask import Flask

app = Flask(__name__)

@app.route('/', methods=["GET"])

def index():

  return 'Hello from Flask'

app.run(host='0.0.0.0', port=81)

 

👉 View the page in your broswer and add a variable or two to the end of the URL like this: 



  



Personalization
If I set my flask code up so that my request.args is assigned to a variable get, then I can use some selection to do some cool personalization.

from flask import Flask, request
app = Flask(__name__)
@app.route('/', methods=["GET"])
def index():
  get = request.args
  if get["name"].lower() == "david":
    return "Hello baldie"
app.run(host='0.0.0.0', port=81)


Look at what this does in the browser:

Return 'no data'
👉 I also need a return "No data" line in case there is no data present.

The reason that return "No data" is not in an else is due to the way that return works.

When a subroutine encounters a return, it exits the sub. So if our name is 'david', then the sub will return 'hello baldie' and then exit. Instead of carrying on to the return "No data".

from flask import Flask, request
app = Flask(__name__)
@app.route('/', methods=["GET"])
def index():
  get = request.args
  if get["name"].lower() == "david":
    return "Hello baldie"
  return "No data"
app.run(host='0.0.0.0', port=81)






Comments

Post a Comment

Popular posts from this blog

Web Scraping

 Web Scraping Some websites don't have lovely APIs for us to interface with. If we want data from these pages, we have to use a tecnique called scraping. This means downloading the whole webpage and poking at it until we can find the information we want. You're going to use scraping to get the top ten restaurants near you. Get started 👉 Go to a website like Yelp and search for the top 10 reastaurants in your location. Copy the URL.   url = "https://www.yelp.co.uk/search?find_desc=Restaurants&find_loc=San+Francisco%2C+CA%2C+United+States"   Import libraries 👉 Import your libraries. Beautiful soup is a specialist library for extracting the contents of HTML and helping us parse them. Run the Repl once your imports are sorted because we want the Beautiful Soup library to be installed (it'll run quicker this way). import requests from bs4 import BeautifulSoup url = "https://www.yelp.co.uk/search?find_desc=Restaurants&find_loc=San+Francisco%2C+CA%2C+Unite...
Post a Comment
Read more

It's Called Hashing,Hashing, Printing the Hash , Salty, Second User ,

 It's Called Hashing One of the big issues with storing usernames and passwords in a database is what happens if we're hacked? If those passwords are stored as text, our users' security is compromised. Probably across multiple sites because they ignored our advice and used the same password for everything!!!!! Hashing  In reality, organizations don't store your actual password. They store a hash of your password. A hash is produced by turning your password into a sequence of numbers, then passing it though a hashing algorithm (some mathematical process that is very difficult to reverse engineer). The data spit out of this hashing algorithm is what's stored instead of your actual password. 👉 So let's do it. I'm using the built-in hash function to create a numerical hash of the password  password = "baldy1" password = hash(password) print(password) # This will output a really long number  👉 Now let's store that hashed version in our database in...
Post a Comment
Read more

Hide & Remove,Come Back!,

 Hide & Remove DISCLAIMER: I promise the good stuff is coming back. We have to go through the valley to get to the mountain, right? Sometimes, we want to remove a button, image or piece of text from the screen. To do this, we use pack_forget(). 👉 We'll start with our default tkinter program. import tkinter as tk window = tk.Tk() window.title("Hello World")  window.geometry("300x200")  hello = tk.Label(text = "Hello World")  hello.pack()  button = tk.Button(text = "Click me!")  button.pack() tk.mainloop() 👉 Now I'm going to add a new subroutine to hide the label and call it on a button click. import tkinter as tk window = tk.Tk() window.title("Hello World")  window.geometry("300x200")  # New subroutine def hideLabel():   hello.pack_forget() # Removes the 'hello' label hello = tk.Label(text = "Hello World")  hello.pack()  button = tk.Button(text = "Click me!", command = hideLabel) # Call...
Post a Comment
Read more