python编程实现12306的一个小爬虫实例

#coding=utf-8 
import requests 
import argparse 
import datetime 
import re 
from prettytable import PrettyTable 
now = datetime.datetime.now() 
 
tomorrow = now+datetime.timedelta(days=1)  
tomorrow = tomorrow.strftime('%Y-%m-%d') 
print tomorrow 
 
argument = argparse.ArgumentParser() 
argument.add_argument('--fromcity','-f',default='hangzhoudong') 
argument.add_argument('--tocity','-t',default='xiamen') 
argument.add_argument('--date','-d',default=tomorrow) 
# argument.add_argument('-d',action='store_true') 
args =argument.parse_args() 
 
from_station = args.fromcity 
to_station = args.tocity 
Date = args.date 
 
stationlist_url = 'https://kyfw.12306.cn/otn/resources/js/framework/station_name.js' 
r = requests.get(stationlist_url, verify=False) 
stationlist = r.content 
 
ToStation = '' 
FromStation = '' 
 
placea = stationlist.find(from_station) 
placeb = stationlist.find(to_station) 
 
for i in range(-4,-1): 
  FromStation += stationlist[placea+i] 
for i in range(-4,-1): 
  ToStation += stationlist[placeb+i] 
 
query_url='https://kyfw.12306.cn/otn/lcxxcx/query?purpose_codes=ADULT&queryDate='+Date+'&from_station='+FromStation+'&to_station='+ToStation 
r = requests.get(query_url,verify=False) 
 
 
with open('json.txt','w') as fp: 
   fp.write(str(r.json())) 
 
if 'datas' in r.json()["data"]: 
  rj = r.json()["data"]["datas"] 
  pt = PrettyTable() 
 
  header = '车次 车站 到站时间 时长 一等座 二等座 软卧 硬卧 硬座 无座'.split() 
  pt._set_field_names(header) 
 
  for x in rj: 
    ptrow = [] 
    ptrow.append(x["station_train_code"]) 
    ptrow.append('\n'.join([x["from_station_name"],x["to_station_name"]])) 
    ptrow.append('\n'.join([x["start_time"], x["arrive_time"]])) 
    ptrow.append(x["lishi"].replace(':','h')+'m') 
    ptrow.append(x['zy_num']) 
    ptrow.append(x['ze_num']) 
    ptrow.append(x['rw_num']) 
    ptrow.append(x['yw_num']) 
    ptrow.append(x['yz_num']) 
    ptrow.append(x['wz_num']) 
    pt.add_row(ptrow) 
  print pt 
else : 
  print '这两个站点没有直达列车'