Flask
Introduction
Quick tour of the python framework flask. Most of this has been taken from https://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-i-hello-world
Getting Started
from app import app
@app.route('/')
@app.route('/index')
def index():
user = {'username': 'Miguel'}
return '''
<html>
<head>
<title>Home Page - Microblog</title>
</head>
<body>
<h1>Hello, ''' + user['username'] + '''!</h1>
</body>
</html>'''
Routing
Templates
So flask like others such pug or egs has templates. Very similar indeed. It supports inheritance for navigation and footers
from flask import render_template
from app import app
@app.route('/')
@app.route('/index')
def index():
user = {'username': 'Miguel'}
posts = [
{
'author': {'username': 'John'},
'body': 'Beautiful day in Portland!'
},
{
'author': {'username': 'Susan'},
'body': 'The Avengers movie was so cool!'
}
]
return render_template('index.html', title='Home', user=user, posts=posts)
And the template
<html>
<head>
{% if title %}
<title>{{ title }} - Microblog</title>
{% else %}
<title>Welcome to Microblog</title>
{% endif %}
</head>
<body>
<h1>Hi, {{ user.username }}!</h1>
{% for post in posts %}
<div><p>{{ post.author.username }} says: <b>{{ post.body }}</b></p></div>
{% endfor %}
</body>
</html>
Forms
Flask uses Flask-WTF for forms which is a wrapper for WTFForms. To configure this we need a secret key which is attached to requests to help prevent CSRF. This is stored in the root or the project e.g. config.py and loaded by the
import os
class Config(object):
SECRET_KEY = os.environ.get('SECRET_KEY') or 'you-will-never-guess'
And in __init__.py
from flask import Flask
from config import Config
app = Flask(__name__)
app.config.from_object(Config)
from app import routes