Python爬取拉勾网招聘信息

此代码运行建议Python3，省却中文编码的麻烦
遇到的几个问题：
（1）拉钩网的数据是通过js的ajax动态生成，所以不能直接爬取，而是通过post’http://www.lagou.com/jobs/positionAjax.json?needAddtionalResult=false‘来获取信息。一开始没有找到positionAjax.json因为没有在jobs这个目录下，在zhaopin目录下找不到这个文件
参考：http://blog.csdn.net/hk2291976/article/details/51284576
（2）http请求头，一开始没有header信息直接被拒绝访问，后来把浏览器的header复制下来就可以了
代码

import requests#http请求头信息headers={'Accept':'application/json, text/javascript, */*; q=0.01','Accept-Encoding':'gzip, deflate, br','Accept-Language':'zh-CN,zh;q=0.8','Connection':'keep-alive','Content-Length':'25','Content-Type':'application/x-www-form-urlencoded; charset=UTF-8','Cookie':'user_trace_token=20170214020222-9151732d-f216-11e6-acb5-525400f775ce; LGUID=20170214020222-91517b06-f216-11e6-acb5-525400f775ce; JSESSIONID=ABAAABAAAGFABEF53B117A40684BFB6190FCDFF136B2AE8; _putrc=ECA3D429446342E9; login=true; unick=yz; showExpriedIndex=1; showExpriedCompanyHome=1; showExpriedMyPublish=1; hasDeliver=0; PRE_UTM=; PRE_HOST=; PRE_SITE=; PRE_LAND=https%3A%2F%2Fwww.lagou.com%2F; TG-TRACK-CODE=index_navigation; Hm_lvt_4233e74dff0ae5bd0a3d81c6ccf756e6=1494688520,1494690499,1496044502,1496048593; Hm_lpvt_4233e74dff0ae5bd0a3d81c6ccf756e6=1496061497; _gid=GA1.2.2090691601.1496061497; _gat=1; _ga=GA1.2.1759377285.1487008943; LGSID=20170529203716-8c254049-446b-11e7-947e-5254005c3644; LGRID=20170529203828-b6fc4c8e-446b-11e7-ba7f-525400f775ce; SEARCH_ID=13c3482b5ddc4bb7bfda721bbe6d71c7; index_location_city=%E6%9D%AD%E5%B7%9E','Host':'www.lagou.com','Origin':'https://www.lagou.com','Referer':'https://www.lagou.com/jobs/list_Python?','User-Agent':'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36','X-Anit-Forge-Code':'0','X-Anit-Forge-Token':'None','X-Requested-With':'XMLHttpRequest'}def get_json(url, page, lang_name):#修改city更换城市    data = {'first': 'true', 'pn': page, 'kd': lang_name,'city':'北京'}#post请求    json = requests.post(url,data, headers=headers).json()    list_con = json['content']['positionResult']['result']    info_list = []    for i in list_con:        info = []        info.append(i['companyId'])#现在没有公司名字，只能看到id        info.append(i['salary'])        info.append(i['city'])        info.append(i['education'])        info_list.append(info)    return info_listdef main():#修改lang_name更换语言类型    lang_name = 'python'    page = 1    url = 'http://www.lagou.com/jobs/positionAjax.json?needAddtionalResult=false'    info_result = []    while page < 31:        info = get_json(url, page, lang_name)        info_result = info_result + info        page += 1   #写入lagou.txt文件中    with open('lagou.txt','w') as f:        for row in info_result:            f.write(str(row)+'\n')if __name__ == '__main__':    main()

结果

根据拉钩网数据的结果，北京Python的工作机会远远超过其他城市，有名的主要使用Python公司也更多，比如豆瓣，知乎，今日头条。

接下来一方面学习多线程和异步来优化爬虫的效率，和应用数据分析来学习处理爬取的数据，比如可视化之类。