Detailed explanation of flask framework

python  web Framework for understanding ：

- django , Instead of , Heavy weapons .

Django: yes python The most widely used web One of the frames . There are very complete official documents , It provides a one-stop mature and reliable solution , Include cache ,ORM, Management backstage , Validation and form processing . Suitable for developing complex database driven websites . however , Because it provides a one-stop solution , The coupling degree of the system is high , It is not easy to replace the built-in functions , The learning curve is also relatively high .

There are many components inside ：ORM、Admin、 middleware 、Form、ModelForm、Session、 cache 、 The signal 、 CRSF;

- flask, short , Expandable , Rich third-party components .

A lightweight customizable framework , Use Python Language writing , More flexible than other similar frameworks 、 Light 、 Safe and easy to use . It can be well combined with MVC Model for development , Developers work together , In a short time, small teams can complete small and medium-sized websites with rich functions or Web Implementation of services . in addition ,Flask And strong customization , Users can add corresponding functions according to their own needs , While keeping the core functions simple, it can enrich and expand the functions , Its powerful plug-in library allows users to achieve personalized website customization , Develop powerful websites .

- tornado, short + Asynchronous non-blocking

It is a non blocking web The server , This is a clear difference from other frameworks , And the speed is quite fast , Thousands of connections can be processed per second . but Tornado It provides the basic modules that the website needs to use , The rest needs to be extended by developers .

flask install ： pip install flask

A complete program ：

Quick display of web pages hello world：

from flask import Flask

 # Configure the default : Take the directory where the current module is located as the root directory Static file directory (static) The template directory (templates)) ,

app = Flask(__name__)

# Bind the view function with the main path

@app.route('/index')

# Defined view function

def index():

    return 'hello world'

if __name__ == "__main__":

    # Simple test server

    app.run()

function ：

* Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)

Then open this website ： http://127.0.0.1:5000/ index

You can see that hello world