中华人民行政部网站爬虫

#中华人民行政部网站爬虫


**今日目标**

爬取该网站行政数据里的县以上最新行政区代码

```
import requests
from lxml import etree
import pymysql
import re

class Govement(object):
    def __init__(self):
        self.one_url = 'http://www.mca.gov.cn/article/sj/' 
                       'xzqh/2019/'
        self.headers = {'User-Agent':'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.100 Safari/537.36'}
        self.db = pymysql.connect(
            'localhost','root','123456','govdb',charset='utf8'
        )
        self.cursor = self.db.cursor()

    # 提取二级页面链接(假链接) 
    def get_false_link(self):
        # xpath: //a[@class="artitlelist"]
        html = requests.get(url = self.one_url,headers = self.headers).content.decode('utf-8','ignore')
        # 解析
        parse_html = etree.HTML(html)
        a_list = parse_html.xpath('//a[@class="artitlelist"]')
        for a in a_list:
            # title = a.xpath('./@title')[0]
            title = a.get('title')
            if re.findall('.*以上行政区划代码',title,re.S):
                two_false_link = 'http://www.mca.gov.cn'+
                                 a.get('href')

                return two_false_link

    # 提取真实二级页面链接(返回数据)
    def get_true_link(self):
        # 获取响应内容
        false_link = self.get_false_link()
        html = requests.get(url=false_link,headers=self.headers).text
        # 打印响应内容,查看真实链接的跳转,匹配出真实链接
        pattern=re.compile(r'window.location.href="(.*?)"',re.S)
        real_link = pattern.findall(html)[0]

        # 实现增量爬取
        # 到version表中查询是否有real_link
        # 有: 数据最新　　没有: 抓数据
        sel = 'select * from version where link="{}"'.format(real_link)

        self.cursor.execute(sel)

        # 链接已存在(不需要抓取数据)
        if self.cursor.fetchall():
            print('数据已是最新')
        else:
            # 先抓数据
            self.get_data(real_link)
            # 把real_link插入到version表中
            ins = 'insert into version values(%s)'
            self.cursor.execute(ins,[real_link])
            self.db.commit()


    # 真正提取数据函数
    def get_data(self,real_link):
        html = requests.get(
            url = real_link,
            headers = self.headers
        ).text
        # 基准xpath: //tr[@height="19"]
        parse_html = etree.HTML(html)
        tr_list = parse_html.xpath('//tr[@height="19"]')
        for tr in tr_list:
            code = tr.xpath('./td[2]/text()')[0]
            name = tr.xpath('./td[3]/text()')[0]
            print(name,code)

    # 主函数
    def main(self):
        self.get_true_link()

if __name__ == '__main__':
    spider = Govement()
    spider.main()

```