抓取大众点评首页左侧信息，如图：

我们要实现把中文名字都存到mongodb，而每个链接存入redis数据库。

因为将数据存到mongodb时每一个信息都会有一个对应的id，那样就方便我们存入redis可以不出错。

# -*- coding: utf-8 -*-
import re
from urllib.request import urlopen
from urllib.request import Request
from bs4 import BeautifulSoup
from lxml import etree
import pymongo


client = pymongo.MongoClient(host="127.0.0.1")
db = client.dianping            #库名dianping
collection = db.classification          #表名classification


import redis        #导入redis数据库
r = redis.Redis(host='127.0.0.1', port=6379, db=0)


# client = pymongo.MongoClient(host="192.168.60.112")
# myip = client['myip']  # 给数据库命名
def secClassFind(selector, classid):
    secItems = selector.xpath('//div[@class="sec-items"]/a')
    for secItem in secItems:
        url = secItem.get('href')       #得到url
        title = secItem.text
        classid = collection.insert({'classname': title, 'pid': classid})
        classurl = '%s,%s' % (classid, url) #拼串
        r.lpush('classurl', classurl)   #入库

def Public(url):
    headers = {'User-Agent': 'Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.6) Gecko/20091201 Firefox/3.5.6'}    #协议头
    req_timeout = 5
    req = Request(url=url, headers=headers)
    f = urlopen(req, None, req_timeout)
    s = f.read()
    s = s.decode("utf-8")
    # beautifulsoup提取
    soup = BeautifulSoup(s, 'html.parser')
    links = soup.find_all(name='li', class_="first-item")
    for link in links:
        selector = etree.HTML(str(link))
        # indexTitleUrls = selector.xpath('//a[@class="index-title"]/@href')
        # # 获取一级类别url和title
        # for titleurl in indexTitleUrls:
        #     print(titleurl)
        indexTitles = selector.xpath('//a[@class="index-title"]/text()')
        for title in indexTitles:
            # 第二级url
            print(title)
            classid = collection.insert({'classname': title, 'pid': None})
            secClassFind(selector, classid)
            print('---------')
        # secItems = selector.xpath('//div[@class="sec-items"]/a')
        # for secItem in secItems:
        #     print(secItem.get('href'))
        #     print(secItem.text)
        print('-----------------------------')
        #
        # myip.collection.insert({'name':secItem.text})
        # r.lpush('mylist', secItem.get('href'))

        # collection.find_one({'_id': ObjectId('5a14c8916d123842bcea5835')})  # connection = pymongo.MongoClient(host="192.168.60.112")  # 连接MongDB数据库


# post_info = connection.myip  # 指定数据库名称（yande_test），没有则创建
# post_sub = post_info.test  # 获取集合名：test
Public('http://www.dianping.com/')