Getting started with website development under the PythonWeb framework Flask

This article mainly introduces the Portal instance for website development under the PythonWeb framework Flask. This article provides a registration page, logon page, and upload page. For more information, see 1. Introduction to Flask

Flask is a Web development microframework implemented by Python. Official website: http://flask.pocoo.org/

II. Demo

1. code structure

The code is as follows:

.
── Blog. py
── Static
│ ── Css
│ ── Index.css
│ ── Images
│ ── Cat.jpg
│ └ ── Sheying1229.jpg
│ ── Js
└ ── Templates
── Index.html
── Login.html
── Regist.html
── Upload.html

5 directories, 8 files

2. main program blog. py

The code is as follows:

#! /Usr/bin/python
# Coding: utf8

From flask import Flask, render_template, url_for, request, redirect, make_response, session
Import OS, MySQLdb

App = Flask (_ name __)
App. secret_key = 'afjlsjfowflajflkajfkjfkaljf'
User_list = ['Jim ', 'Max', 'py']

Imagepath = OS. path. join (OS. getcwd (), "static/images ")

@ App. route ('/')
Def index ():
Username = request. cookies. get ('Username ')
If not username:
Username = U' log on first'
Islogin = session. get ('islogin ')
Nav_list = [u 'homepage ', u 'economical', u 'cultural ', u 'tech', u 'entertaining ']
Blog = {'Title': 'Welcome to my blog ', 'content': 'Hello, welcome to my blog .'}
Blogtag = {'javascript ': 10, "python": 20, "shell": 5}
Img = url_for ('static ', filename = "images/cat.jpg ")
Return render_template('index.html ', nav_list = nav_list, username = username, blog = blog, blogtag = blogtag, img = img, islogin = islogin)

@ App. route ('/reg', methods = ['GET', 'post'])
Def regist ():
If request. method = 'Post ':
Username = request. form ['username']
Conn = MySQLdb. connect (user = 'root', passwd = 'admin', host = '2017. 0.0.1 ')
Conn. select_db ('blog ')
Curr = conn. cursor ()
SQL = 'Insert into 'user' ('id', 'Username') values (% d, "% s") '% (1, username)
Curr.exe cute (SQL)
Conn. commit ()
Curr. close ()
Conn. close ()
Return "user % s regist OK! "% Request. form ['username']
Else:
# Request. args ['username']
Return render_template('regist.html ')

@ App. route ('/upload', methods = ['GET', 'post'])
Def upload ():
If request. method = 'Post ':
Username = request. form ['username']
File = request. files ['IMG ']
Filename = file. filename
File. save (OS. path. join (imagepath, filename ))
Return "" % filename
Else:
Return render_template('upload.html ')

@ App. route ('/login/', methods = ['GET', 'post'])
Def login ():
If request. method = 'Post ':
Username = request. form. get ('Username ')
If username in user_list:
Response = make_response (redirect ('/'))
Response. set_cookie ('username', value = username, max_age = 300)
Session ['islogin'] = '1'
Return response
Else:
Session ['islogin'] = '0'
Return redirect ('/login /')
Else:
Return render_template('login.html ')

If _ name _ = '_ main __':
App. run (debug = True, host = '0. 0.0.0 ', port = 5000)

It mainly includes the homepage, registration, logon, and upload pages.

Blog. py shows common functions and usage of Flask: routing, database operations, cookie, session, redirect, form, file upload, debugging, IP address and port of the Web server, static file reading.

3rd, the first page template index.html

The code is as follows:

Flask DEMO

{% If islogin = '1' %}
Welcome, {username }}!
{% Else %}
{Username }}!
{% Endif %}

{% For nav in nav_list %}

• {Nav }}

{% Endfor %}

{Blog ['title']}

{Blog ['content']}

{% For key, value in blogtag. items () %}

• {Key }}( {value }})

{% Endfor %}

This template mainly shows how to read various types of variables in the Flask template.

Login.html

The code is as follows:

Login

Login

The combination of blog. py mainly shows how the form submits values, cookie and session applications.

5 forbidden registration page regist.html

The code is as follows:

Regist

Regist

Combined with blog. py, it mainly shows database operations.

6、upload page upload.html

The code is as follows:

Upload

Upload

The combination of blog. py mainly shows how to upload files.

7. running effect