爬取站点  https://it.ithome.com/ityejie/ ，进入详情页提取内容。

1 import requests  2 import json  3 from lxml import etree  4 from pymongo import MongoClient  5   6 url = 'https://it.ithome.com/ithome/getajaxdata.aspx'  7 headers = {  8     'authority': 'it.ithome.com',  9     'method': 'POST', 10     'path': '/ithome/getajaxdata.aspx', 11     'scheme': 'https', 12     'accept': 'text/html, */*; q=0.01', 13     'accept-encoding': 'gzip, deflate, br', 14     'accept-language': 'zh-CN,zh;q=0.9', 15     'content-length': '40', 16     'content-type': 'application/x-www-form-urlencoded; charset=UTF-8', 17     'cookie': 'BAIDU_SSP_lcr=https://www.hao123.com/link/https/?key=http%3A%2F%2Fwww.ithome.com%2F&&monkey=m-kuzhan-group1&c=B329C2F33C91DEACCFAEB1680305F198; Hm_lvt_f2d5cbe611513efcf95b7f62b934c619=1530106766; ASP.NET_SessionId=tyxenfioljanx4xwsvz3s4t4; Hm_lvt_cfebe79b2c367c4b89b285f412bf9867=1530106547,1530115669; BEC=228f7aa5e3abfee5d059195ad34b4137|1530117889|1530109082; Hm_lpvt_f2d5cbe611513efcf95b7f62b934c619=1530273209; Hm_lpvt_cfebe79b2c367c4b89b285f412bf9867=1530273261', 18     'origin': 'https://it.ithome.com', 19     'referer': 'https://it.ithome.com/ityejie/', 20     'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3472.3 Safari/537.36', 21     'x-requested-with': 'XMLHttpRequest' 22 } 23  24 client = MongoClient() 25 db = client['ithome'] 26 collection = db['ithome'] 27 max_page = 1000 28  29 def get_page(page):   30  31     formData = { 32         'categoryid': '31', 33         'type': 'pccategorypage', 34         'page': page, 35         } 36     try: 37         r = requests.post(url, data=formData, headers=headers) 38         if r.status_code == 200: 39  40             #print(type(r)) 41             html = r.text 42             # 响应返回的是字符串，解析为HTML DOM模式 text = etree.HTML(html) 43             text = etree.HTML(html) 44             link_list = text.xpath('//h2/a/@href')  45  46             print("提取第"+str(page)+"页文章") 47             id=0 48             for link in link_list: 49                 id+=1 50                 print("解析第"+str(page)+"页第"+str(id)+"篇文章") 51                 print("链接为："+link) 52                 loadpage(link) 53  54     except requests.ConnectionError as e: 55         print('Error', e.args)     56  57  58 # 取出每个文章的链接 59 def loadpage(link): 60  61     headers = {
   'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3472.3 Safari/537.36'} 62  63     try: 64   65         reseponse = requests.get(link, headers = headers) 66         if reseponse.status_code == 200:      67             html = reseponse.text 68             # 解析 69             node = etree.HTML(html) 70  71             ithome ={} 72             # 取出每个标题，正文等 73  74             # xpath返回的列表，这个列表就这一个参数，用索引方式取出来，标题 75             ithome['title'] = node.xpath('//*[@id="wrapper"]/div[1]/div[2]/h1')[0].text 76             # 时间 77             ithome['data'] = node.xpath('//*[@id="pubtime_baidu"]')[0].text 78             # 取出标签下的内容 79             #content = node.xpath('//*[@id="paragraph"]/p/text()') 80             ithome['content'] = "".join(node.xpath('//*[@id="paragraph"]/p/text()')).strip() 81             #content = node.xpath('//*[@id="paragraph"]/p')[1].text 82             # 取出标签里包含的内容，作者 83             ithome['author'] = node.xpath('//*[@id="author_baidu"]/strong')[0].text 84             # 评论数 85             ithome['commentcount'] = node.xpath('//span[@id="commentcount"]')[0].text 86             #评论数没有取到 87             write_to_file(ithome) 88             save_to_mongo(ithome)              89  90     except requests.ConnectionError as e: 91         print('Error', e.args)   92  93 def write_to_file(content): 94     with open('ithome.json','a',encoding='utf-8') as f: 95         f.write(json.dumps(content,ensure_ascii=False)+'\n') 96         f.close() 97  98 def save_to_mongo(result): 99     if collection.insert(result):100         print('Saved to Mongo')101 102 if __name__ == '__main__':103     for page in range(1, max_page + 1):104         get_page(page)105 106