web框架之初识Django

import socket

server = socket.socket()
server.bind(('127.0.0.1', 8080))
server.listen(5)
"""
请求首行
b'GET / HTTP/1.1\r\n
请求头
Host: 127.0.0.1:8080\r\n
Connection: keep-alive\r\n
Cache-Control: max-age=0\r\n
Upgrade-Insecure-Requests: 1\r\n
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.97 Safari/537.36\r\n
Sec-Fetch-User: ?1\r\n
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3\r\n
Sec-Fetch-Site: none\r\n
Sec-Fetch-Mode: navigate\r\n
Accept-Encoding: gzip, deflate, br\r\n
Accept-Language: zh-CN,zh;q=0.9\r\n
Cookie: csrftoken=aOZSalMQkKGbzstfjcw3O9sDoegdywL8AD7PzhidAyx3tXShN7oQtxN1MMnS6GVX\r\n
\r\n(******)
请求体
"""
while True:
    conn, addr = server.accept()  # 阻塞态
    data = conn.recv(1024)
    # print(data)
    conn.send(b'HTTP/1.1 200 OK\r\n\r\n')
    data_str = data.decode('utf-8')
    current_path = data_str.split('\r\n')[0].split(' ')[1]
    # print(current_path)
    if current_path == '/index':
        # conn.send(b'index')
        with open(r'01 纯手撸的前端页面.html','rb') as f:
            conn.send(f.read())
    elif current_path == '/login':
        conn.send(b'login')
    else:
        conn.send(b'404 error')
    conn.close()

from wsgiref.simple_server import make_server
from urls import urls
from views import *

def run(env,response):
    """
    :param env: 请求相关的所有数据 将http数据全部提前处理成了字典的形式 供调用者使用
    :param response: 响应相关的所有数据
    :return: 给前端真正的数据
    """
    # print(env)
    response('200 OK',[('xxx','zgh'),])
    current_path = env.get('PATH_INFO')
    # print(current_path)
    # if current_path == '/index':
    #     return [b'index']
    # elif current_path == '/login':
    #     return [b'login']
    # 定义一个存储函数名的标志位
    func = None
    for url in urls:  # url =  ('/login',login)  ('/index',index)
        if current_path == url[0]:  # 用户敲的后缀名 你后端有对应的处理业务
            func = url[1]  # 将匹配上的函数名赋值给func变量
            break  # 一旦用户匹配上了对应的业务接口 立刻结束匹配
    # 判断func是否被赋值
    if func:
        res = func(env)
    else:
        res = error(env)
    return [res.encode('utf-8'),]


if __name__ == '__main__':
    server = make_server('127.0.0.1',8080,run)  # 实时监听本机8080端口
    # 一旦有请求来了 会统一交给run函数处理(调用run函数并传参run(env,response))
    server.serve_forever()  # 启动服务端

from views import *

urls = [
    ('/login',login),
    ('/index',index),
    ('/reg',reg),
    ('/xxx',xxx),
    ('/get_time',get_time),
    ('/get_userdict',get_userdict),
    ('/get_data',get_data),
]

def login(env):
    return 'login'

def index(env):
    return 'index'

def reg(env):
    return 'reg'

def xxx(env):
    # return 'xxx'
    with open(r'templates/02 xxx.html','r',encoding='utf-8') as f:
        return f.read()

def error(env):
    return '404 error'


import time
def get_time(env):
    ctime = time.strftime('%Y-%m-%d %X')
    # 后端数据 如何传递给html页面（利用字符串的替换）
    with open(r'templates/03 get_time.html','r',encoding='utf-8') as f:
        data = f.read()
    data = data.replace('sadadadasdsadsad',ctime)
    return data


from jinja2 import Template
def get_userdict(env):
    user_dic = {'username':'jason','age':18,'hobby':['read','book','run']}
    with open(r'templates/04 get_user.html','r',encoding='utf-8') as f:
        data = f.read()
    temp = Template(data)
    res = temp.render(userDic = user_dic)  # 将user_dic传递给html页面 页面上通过userDic就能够拿到后端传递过来的值
    return res

import pymysql
def get_data(env):
    conn = pymysql.connect(
        host = '127.0.0.1',
        port = 3306,
        user = 'root',
        password = '123qwe',
        db = 'day49',
        charset = 'utf8',
        autocommit = True
    )
    cursor = conn.cursor(pymysql.cursors.DictCursor)  # 将查出来的数据组织成一个字典
    sql = "select * from userinfo"  # 关键性的数据 不要自己手动拼接
    affect_rows = cursor.execute(sql)  # sql注入:就是利用MySQL注释语法
    # print(affect_rows)
    user_list = cursor.fetchall()
    # print(user_list)
    # return 'hahahahha'
    with open(r'templates/05 get_data.html','r',encoding='utf-8') as f:
        data = f.read()
    temp = Template(data)
    res = temp.render(user_list = user_list)
    return res

def login(request):
    user_dic = {'username':'xiaozhu','password':'123'}
    return render(request,'login.html',{'user_info':user_dic})

def home(request):
    #return redirect('/login')如果重定向为本站的其他页面则可直接写本站其他页面的后缀
    return redirect('https://www.cnblogs.com/ghylpb/')#如果重定向为其他网站则直接写其它网站的网址即可