Python-网络编程

一、模拟网络编程

1、在服务器创建接口：导入flask模块（python面向web开发的框架）

2、客户端给服务器发送请求：导入requests模块（发送网络请求）

二、服务器创建接口

import flask
from flask import request
import pymysql


def connect_mysql(sql):
    conn = pymysql.connect(host='127.0.0.1', user='root', password='123456', db='mytable', charset='utf8')
    cur = conn.cursor()
    cur.execute(sql)
    data = cur.fetchall()
    if 'select' not in sql:
        conn.commit()
    cur.close()
    conn.commit()
    return data

server = flask.Flask(__name__)  #创建web接口


@server.route('/login', methods=['get','post'])  #登录页，methods默认为get请求
def login():
    cookie = request.cookies.get('sign')         #获取cookies中指定key对应的value
    # print(request.cookies)                     #获取请求发过来的cookies
    username = request.values.get('username','') #获取请求参数data中指定key对应的value
    password = request.values.get('password','')
    # username = request.json.get('username')    #获取请求参数json中指定key对应的value
    # password = request.json.get('password')
    sql = 'select * from userinfo where username = "%s" and password = "%s"'%(username, password)
    if username and password and cookie:
        if connect_mysql(sql) and cookie == '1': #暂将cookie写死，仅模拟传参
            return '{"msg":"登录成功","code":"200"}'
        else:
            return '{"msg":"用户名密码错误或cookie错误","code":"301"}'
    else:
        return '{"msg":"缺少参数","code":300}'

server.run(port=8000,debug=True) #启动server,port默认为5000

三、客户端发送请求

import requests

url = 'http://127.0.0.1:8000/login'
data = {'username': 'xsj', 'password': '123456'}
cookie = {'sign': '1'}
r = requests.get(url, data=data, json=data, cookies=cookie) #data必须是dict类型；请求中可添加json/cookies等参数
print(r.status_code)  #打印返回码
print(r.text)    #以字符串形式，打印请求结果
print(r.content) #以二进制形式，打印请求结果
print(r.json())  #返回结果是json类型时，可获取json类型
print(r.url)     #打印请求url
print(r.headers) #打印headers