面向函数——>面向对象；
只涉及列表页，详情页没有涉及；
所以只要一个类：CFDA，就够了。/20180225
__author__ = '姜枫渔火'

import requests, time, random
from fake_useragent import UserAgent

class CFDA():
    def __init__(self):
        self.url = 'http://125.35.6.84:81/xk/itownet/portalAction.do?method=getXkzsList'
        self.headers = {'User-Agent': UserAgent().random}
        self.data = {'on':'true',
                    'page':'1',
                    'pageSize':'15',
                    'productName':'',
                    'conditionType':'1',
                    'applyname':'',
                    'applysn':''}

    def getData(self, data):
        try:
            response = requests.post(self.url, data = data, headers = self.headers, timeout = 3)
            if response.status_code == 200:
                html = response.json()
                # print(html)
                return html
        except requests.exceptions.RequestException as e:
            print(e)
            return None
        except requests.exceptions.ConnectTimeout as e:
            print(e)
            return None

    def extractData(self, html):
        name_list = []
        try:
            for i in range(len(html['list'])):
                cfda_data = html['list'][i]['EPS_NAME']
                # print(cfda_data)
                name_list.append(cfda_data)
            return name_list
        except:
            print('!!!')
            return None

    def writeData(self, cfda_data):
        with open('CFDA.txt', 'a') as f:
            f.write(cfda_data + '\n')

    def run(self):
        for page in range(1, int(d)+1):
            print('第{}页：'.format(str(page)))
            time.sleep(random.uniform(1,3))
            self.data['page'] = str(page)
            one_page = self.getData(self.data)
            for i in self.extractData(one_page):
                print(i)
                self.writeData(i)
        print('任务完成')


if __name__ == '__main__':
    d = input('请输入爬取深度：')
    cfda = CFDA()
    cfda.run()