Python_爬虫_案例汇总：

1.豆瓣采集

#coding:utf-8
#采集豆瓣书信息和图片，写进数据库 

from urllib import request
# from bs4 import BeautifulSoup
from lxml import etree
import json,pymysql

# from my_pymysql import pymysql

url="https://book.douban.com/tag/%E5%B0%8F%E8%AF%B4"
headers={
    'Host':'book.douban.com',
    'Upgrade-Insecure-Requests':'1',
    'User-Agent':'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.140 Safari/537.36'
}
req = request.Request(url=url,headers=headers,method="GET")
content = request.urlopen(req).read().decode("utf-8")
content_dict=etree.HTML(content)    #格式化
# print(content_dict)
content_dict_allli = content_dict.xpath(r'//*[@id="subject_list"]/ul/li')  #拿到列表
info_all = ''

for li in content_dict_allli:     
    # 书名/标题
    title_list = li.xpath(r'div[2]/h2/a/@title')    #取标签里的内容，注意地址是相对地址，不能直接拿来用 （注：和bs4不一样）
    title =title_list[0]
    title=title.replace(" ",'')
    print(title)
    #信息 作者、出版社
    info_list = li.xpath(r'div[2]/div[1]/text()') 
    author = info_list[0].split('/')[0]
    author = author.replace('
','').replace(" ",'')
    chubanshe = info_list[0].split('/')[1]
    print(author)
    print(chubanshe)
    #评分
    pingfen_list = li.xpath(r'div[2]/div[2]/span[2]/text()')
    pingfen = pingfen_list[0]
    print(pingfen)

    #图片
    img_net_addr =li.xpath(r'div[1]/a/img/@src')
    img_net_addr = img_net_addr[0]
    print(img_net_addr)
    data = request.urlopen(img_net_addr).read()
    img_name =str('douban/') + title + str('.jpg')
    with open(img_name,'wb')as f:
        f.write(data)
        
    #数据库
    db = pymysql.connect(host='localhost',port=3306,user="root",password='root',db='douban',charset='utf8')    #
    cur=db.cursor()
    sql = "insert into douban(title,author,chubanshe,pingfen)values('%s','%s','%s','%s')"%(title,author,chubanshe,pingfen)
    cur.execute(sql)
    db.commit()

db.close()

2.链家

#coding:utf-8
#完成，，取出链家数据存到文件里
from urllib import request,error
from bs4 import BeautifulSoup
import pymysql

# from my_pymysql import pymysql  #引入数据库
#创建数据库
db = pymysql.connect(host='localhost',user='root',password='root',db='lianjia',charset='utf8')
cur = db.cursor()   #实例化游标

for i in range(1,33):
    req=request.urlopen('https://xa.lianjia.com/ershoufang/pg'+str(i)).read().decode('utf-8')
    req_bs4 = BeautifulSoup(req,'html.parser')  #建立对象，才能用bs4
    body_ul=req_bs4.find('ul',class_="sellListContent")
    try:
        s=''
        for li in body_ul:
            # info_all = li.find('div',class_="info clear").get_text()    #全部信息
            tit = li.find('div',class_="title").get_text()  #标题
            addr = li.find('div',class_="houseInfo").get_text() #地址
            pric = li.find('div',class_="totalPrice").get_text()    #价格
            s+=tit
            s+=addr
            s+=pric
            s+='

'
            print(i)    #提示采集的位置
             # 采集图片开始++++++++++++++++++++++++++++++++++++++++++++
            img = li.find("img", class_='lj-lazy')['data-original'] #图片地址
            img_format = img.split('.')[-1]  # 用点隔开，取图片的后缀
            img_name = 'lianjia/images/' + li.find("img", class_='lj-lazy')['alt'] + '.' + img_format  # 名字
            adr = request.urlopen(img).read()  # 读取图片地址，拿到字节流形式的图片，，写进去
            try:    #；空的话就跳过
                with open(img_name, 'wb')as f:
                    f.write(adr)
            except:
                pass
            # 采集图片完毕----------------------------
            #存到数据库
            sql = "insert into lianjia_hotel(title,address) values ('%s','%s')"%(tit,addr)
            cur.execute(sql)
            db.commit()
    except:
        print("本页完毕~")
#最后再关闭数据库
db.close()

#写到一个txt文件里面
# with open('lianjia/lianjia.txt','w',encoding="utf-8")as f:
#     f.write(s)

3.今日头条

from selenium import webdriver
from lxml import etree
from pyquery import PyQuery as pq
import time

driver = webdriver.Chrome()
driver.maximize_window()
driver.get('https://www.toutiao.com/')
driver.implicitly_wait(10)
driver.find_element_by_link_text('科技').click()
driver.implicitly_wait(10)
for x in range(3):
    js="var q=document.documentElement.scrollTop="+str(x*500)
    driver.execute_script(js)
    time.sleep(2)

time.sleep(5)
page = driver.page_source
doc = pq(page)
doc = etree.HTML(str(doc))
contents = doc.xpath('//div[@class="wcommonFeed"]/ul/li')
print(contents)
for x in contents:
    title = x.xpath('div/div[1]/div/div[1]/a/text()')
    if title:
        title = title[0]
        with open('toutiao.txt','a+',encoding='utf8')as f:
            f.write(title+'
')
        print(title)
    else:
        pass

4.微信群信息(包括成员)和联系人

# -*- coding:utf-8 -*-
'''
扫码登陆微信后获取该微信账号的微信群(包括群内人员)和通讯录联系人信息【注：好像不全】
'''

import os
import re
import time
import sys
import subprocess
import requests
import xml.dom.minidom
import json


# 微信登陆
class WebwxLogin(object):
    def __init__(self):
        self.session = requests.session()
        self.headers = {
            'User-Agent': 'Mozilla/5.0 (Windows NT 5.1; rv:33.0) Gecko/20100101 Firefox/33.0'}
        self.QRImgPath = os.path.split(os.path.realpath(__file__))[0] + os.sep + 'webWeixinQr.jpg'
        self.uuid = ''
        self.tip = 0
        self.base_uri = ''
        self.redirect_uri = ''
        self.skey = ''
        self.wxsid = ''
        self.wxuin = ''
        self.pass_ticket = ''
        self.deviceId = 'e000000000000000'
        self.BaseRequest = {}
        self.ContactList = []
        self.My = []
        self.SyncKey = ''

    def getUUID(self):

        url = 'https://login.weixin.qq.com/jslogin'
        params = {
            'appid': 'wx782c26e4c19acffb',
            'redirect_uri': 'https://wx.qq.com/cgi-bin/mmwebwx-bin/webwxnewloginpage',
            'fun': 'new',
            'lang': 'zh_CN',
            '_': int(time.time() * 1000),  # 时间戳
        }

        response = self.session.get(url, params=params)
        target = response.content.decode('utf-8')

        pattern = r'window.QRLogin.code = (d+); window.QRLogin.uuid = "(S+?)"'
        ob = re.search(pattern, target)  # 正则提取uuid

        code = ob.group(1)
        self.uuid = ob.group(2)

        if code == '200':  # 判断请求是否成功
            return True

        return False

    def showQRImage(self):

        url = 'https://login.weixin.qq.com/qrcode/' + self.uuid
        response = self.session.get(url)

        self.tip = 1

        with open(self.QRImgPath, 'wb') as f:
            f.write(response.content)
            f.close()
        # 打开二维码
        if sys.platform.find('darwin') >= 0:
            subprocess.call(['open', self.QRImgPath])  # 苹果系统
        elif sys.platform.find('linux') >= 0:
            subprocess.call(['xdg-open', self.QRImgPath])  # linux系统
        else:
            os.startfile(self.QRImgPath)  # windows系统

        print('请使用微信扫描二维码登录')

    def checkLogin(self):

        url = 'https://login.weixin.qq.com/cgi-bin/mmwebwx-bin/login?tip=%s&uuid=%s&_=%s' % (
            self.tip, self.uuid, int(time.time() * 1000))

        response = self.session.get(url)
        target = response.content.decode('utf-8')

        pattern = r'window.code=(d+);'
        ob = re.search(pattern, target)
        code = ob.group(1)

        if code == '201':  # 已扫描
            print('成功扫描,请在手机上点击确认登录')
            self.tip = 0
        elif code == '200':  # 已登录
            print('正在登录中...')
            regx = r'window.redirect_uri="(S+?)";'
            ob = re.search(regx, target)
            self.redirect_uri = ob.group(1) + '&fun=new'
            self.base_uri = self.redirect_uri[:self.redirect_uri.rfind('/')]
        elif code == '408':  # 超时
            pass

        return code

    def login(self):

        response = self.session.get(self.redirect_uri, verify=False)
        data = response.content.decode('utf-8')

        doc = xml.dom.minidom.parseString(data)
        root = doc.documentElement
        # 提取响应中的参数
        for node in root.childNodes:
            if node.nodeName == 'skey':
                self.skey = node.childNodes[0].data
            elif node.nodeName == 'wxsid':
                self.wxsid = node.childNodes[0].data
            elif node.nodeName == 'wxuin':
                self.wxuin = node.childNodes[0].data
            elif node.nodeName == 'pass_ticket':
                self.pass_ticket = node.childNodes[0].data

        if not all((self.skey, self.wxsid, self.wxuin, self.pass_ticket)):
            return False

        self.BaseRequest = {
            'Uin': int(self.wxuin),
            'Sid': self.wxsid,
            'Skey': self.skey,
            'DeviceID': self.deviceId,
        }

        return True

    def webwxinit(self):

        url = self.base_uri + 
              '/webwxinit?pass_ticket=%s&skey=%s&r=%s' % (
                  self.pass_ticket, self.skey, int(time.time() * 1000))
        params = {
            'BaseRequest': self.BaseRequest
        }

        h = self.headers
        h['ContentType'] = 'application/json; charset=UTF-8'
        response = self.session.post(url, data=json.dumps(params), headers=h, verify=False)
        data = response.content.decode('utf-8')
        print(data)

        dic = json.loads(data)
        self.ContactList = dic['ContactList']
        self.My = dic['User']

        SyncKeyList = []
        for item in dic['SyncKey']['List']:
            SyncKeyList.append('%s_%s' % (item['Key'], item['Val']))
        self.SyncKey = '|'.join(SyncKeyList)

        ErrMsg = dic['BaseResponse']['ErrMsg']

        Ret = dic['BaseResponse']['Ret']
        if Ret != 0:
            return False

        return True

    def webwxgetcontact(self):

        url = self.base_uri + 
              '/webwxgetcontact?pass_ticket=%s&skey=%s&r=%s' % (
                  self.pass_ticket, self.skey, int(time.time()))

        h = self.headers
        h['ContentType'] = 'application/json; charset=UTF-8'
        response = self.session.get(url, headers=h, verify=False)
        data = response.content.decode('utf-8')
        # print(data)

        dic = json.loads(data)
        MemberList = dic['MemberList']

        # 倒序遍历,不然删除的时候出问题..
        SpecialUsers = ["newsapp", "fmessage", "filehelper", "weibo", "qqmail", "tmessage", "qmessage", "qqsync",
                        "floatbottle", "lbsapp", "shakeapp", "medianote", "qqfriend", "readerapp", "blogapp",
                        "facebookapp", "masssendapp",
                        "meishiapp", "feedsapp", "voip", "blogappweixin", "weixin", "brandsessionholder",
                        "weixinreminder", "wxid_novlwrv3lqwv11", "gh_22b87fa7cb3c", "officialaccounts",
                        "notification_messages", "wxitil", "userexperience_alarm"]
        for i in range(len(MemberList) - 1, -1, -1):
            Member = MemberList[i]
            if Member['VerifyFlag'] & 8 != 0:  # 公众号/服务号
                MemberList.remove(Member)
            elif Member['UserName'] in SpecialUsers:  # 特殊账号
                MemberList.remove(Member)
            elif Member['UserName'].find('@@') != -1:  # 群聊
                MemberList.remove(Member)
            elif Member['UserName'] == self.My['UserName']:  # 自己
                MemberList.remove(Member)

        return MemberList

    def main(self):
        if not self.getUUID():
            print('获取uuid失败')
            return

        self.showQRImage()
        time.sleep(1)

        while self.checkLogin() != '200':
            pass

        os.remove(self.QRImgPath)

        if not self.login():
            print('登录失败')
            return
        # 登录完成, 下面查询好友
        if not self.webwxinit():
            print('初始化失败')
            return

        MemberList = self.webwxgetcontact()

        print('通讯录共%s位好友' % len(MemberList))

        for x in MemberList:
            sex = '未知' if x['Sex'] == 0 else '男' if x['Sex'] == 1 else '女'
            print('昵称:%s, 性别:%s, 备注:%s, 签名:%s' % (x['NickName'], sex, x['RemarkName'], x['Signature']))

if __name__ == '__main__':
    print('开始')
    wx = WebwxLogin()
    wx.main()

5.爬取淘宝固定类别商品信息+保存到mysql数据库【格式很规范】

import requests
import re
import pymysql


def getHTMLtext(url):
    try:
       r=requests.get(url,timeout=100)
       r.raise_for_status()
       r.encoding=r.apparent_encoding
       return r.text
    except:
        return ""
def getpage(itl,html):
    try:
        plt=re.findall(r'"view_price":"[d.]*"',html)
        nlt=re.findall(r'"raw_title":".*?"',html)
        for i in range(len(plt)):
            price = eval(plt[i].split(':')[1])  # eval(fun,obj)
            title = eval(nlt[i].split(':')[1])
            itl.append([price, title])
    except:
       print("")


def printgoods(itl):
    tplt = "{:2}	{:8}	{:16}"
    print(tplt.format("序号", "价格", "商品名称"))

    count = 0
    conn = pymysql.connect(host='127.0.0.1', user='root', password='123456', db='company',charset="utf8")

    cur = conn.cursor()

    sqlc = '''
                create table coffee(
                id int(11) not null auto_increment primary key,
                name varchar(255) not null,
                price float not null)DEFAULT CHARSET=utf8;
                '''

    try:
        A = cur.execute(sqlc)
        conn.commit()
        print('成功')
    except:
        print("错误")
    for g in itl:
        count = count + 1
        b=tplt.format(count, g[0], g[1])



        sqla = '''
        insert into  coffee(name,price)
        values(%s,%s);
       '''
        try:
            B = cur.execute(sqla,(g[1],g[0]))
            conn.commit()
            print('成功')
        except:
            print("错误")

        # save_path = 'D:/taobao.txt'
        # f=open(save_path,'a')
        #
        # f.write(b+'
')
        # f.close()

    conn.commit()
    cur.close()
    conn.close()


def main():
    goods="咖啡"
    depth =2
    start_url='https://s.taobao.com/search?q='+goods
    List =[]
    for i in range(depth):
        try:
            url =start_url +"&s="+ str(i*44)
            html=getHTMLtext(url)
            getpage(List,html)
        except:
           continue


    print(printgoods(List))
    # savefiles(data)




main()

6.Ajax请求，模范代码

import requests
import logging
import json
from os import makedirs
from os.path import exists

# 总页数 
TOTAL_PAGE = 2
# 文件存放位置
RESULTS_DIR = 'results'
exists(RESULTS_DIR) or makedirs(RESULTS_DIR)
# 日志配置
logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s: %(message)s')
# 起始url
INDEX_URL = 'https://dynamic1.scrape.center/api/movie/?limit={limit}&offset={offset}'
# 页数
LIMIT = 2
# 详情页url
DETAIL_URL = 'https://dynamic1.scrape.center/api/movie/{id}'


def scrape_api(url):
    logging.info('scraping %s...', url)
    try:
        response = requests.get(url)
        if response.status_code == 200:
            return response.json()
        logging.error('get invalid status code %s while scraping %s', response.status_code, url)
    except requests.RequestException:
        logging.error('error occurred while scraping %s', url, exc_info=True)


def scrape_index(page):
    url = INDEX_URL.format(limit=LIMIT, offset=LIMIT * (page - 1))
    return scrape_api(url)


def scrape_detail(id):
    url = DETAIL_URL.format(id=id)
    return scrape_api(url)


def save_data(data):
    name = data.get('name')
    data_path = f'{RESULTS_DIR}/{name}.json'
    json.dump(data, open(data_path, 'w', encoding='utf-8'), ensure_ascii=False, indent=2)


def main():
    for page in range(1, TOTAL_PAGE + 1):
        index_data = scrape_index(page)
        for item in index_data.get('results'):
            id = item.get('id')
            detail_data = scrape_detail(id)
            logging.info('detail data %s', detail_data)
            save_data(detail_data)


if __name__ == '__main__':
    main()