why i can't get the result from lagou this web site by using web scraping - python-3.x

Question

I m using python 3.6.5 and my os system is macOS 10.13.6.
I m learning Web Scraping and I want to catch data from this web site(https://www.lagou.com/jobs/list_python?labelWords=&fromSearch=true&suginput=)
Here is my code:
# encoding: utf-8
import requests
from lxml import etree
def parse_list_page():
url = 'https://www.lagou.com/jobs/positionAjax.json?city=%E6%B7%B1%E5%9C%B3&needAddtionalResult=false'
headers = {
'User-Agent':'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.109 Safari/537',
'Host':'www.lagou.com',
'Referer':'https://www.lagou.com/jobs/list_python?labelWords=&fromSearch=true&suginput=',
'X-Anit-Forge-Code':'0',
'X-Anit-Forge-Token':None,
'X-Requested-With':'XMLHttpRequest',
}
data = {
'first':'false',
'pn':1,
'kd':'python',
}
response = requests.post(url,headers=headers,data=data)
print(response.json())
def main():
parse_list_page()
if __name__ == '__main__':
main()
I m appreciate you for spending the time to answer my question.

Answer 1

I got the answer, here is the code below:
# encoding: utf-8
import requests
from lxml import etree
import time
def parse_list_page():
url = 'https://www.lagou.com/jobs/list_python?px=default&city=%E6%B7%B1%E5%9C%B3'
headers = {
'User-Agent':'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.109 Safari/537',
'Host':'www.lagou.com',
'Referer':'https://www.lagou.com/',
'Connection':'keep-alive',
'Accept-Encoding':'gzip, deflate, br',
'Accept-Language':'zh-CN,zh;q=0.9,en;q=0.8',
'Upgrade-Insecure-Requests':'1',
'Accept':'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8',
'Cache-Control':'no-cache',
'Pragma':'no-cache',
}
response = requests.get(url,headers=headers)
# print(response.text)
r = requests.utils.dict_from_cookiejar(response.cookies)
print(r)
print('='*30)
# r['LGUID'] = r['LGRID']
# r['user_trace_token'] = r['LGRID']
# r['LGSID'] = r['LGRID']
cookies = {
# 'X_MIDDLE_TOKEN':'df7c1d3cfdf279f0caf13df990723620',
# 'JSESSIONID':'ABAAABAAAIAACBI29FE9BDFB6838D8DD69C580E517292C9',
# '_ga':'GA1.2.820168368.1551196380',
# '_gat':'1',
# 'Hm_lvt_4233e74dff0ae5bd0a3d81c6ccf756e6':'1551196381',
# 'user_trace_token':'20190226235303-99bc357a-39de-11e9-921f-525400f775ce',
# 'LGSID':'20190311094827-c3bc2393-439f-11e9-a15a-525400f775ce',
# 'PRE_UTM':'',
# 'PRE_HOST':'',
# 'PRE_SITE':'',
# 'PRE_LAND':'https%3A%2F%2Fwww.lagou.com%2F',
# 'LGUID':'20190226235303-99bc3944-39de-11e9-921f-525400f775ce',
# '_gid':'GA1.2.1391680888.1552248111',
# 'index_location_city':'%E6%B7%B1%E5%9C%B3',
# 'TG-TRACK-CODE':'index_search',
# 'LGRID':'20190311100452-0ed0525c-43a2-11e9-9113-5254005c3644',
# 'Hm_lpvt_4233e74dff0ae5bd0a3d81c6ccf756e6':'1552269893',
# 'SEARCH_ID':'aae3c38ec76545fc86cd4e23153afe44',
}
cookies.update(r)
print(r)
print('=' * 30)
print(cookies)
print('=' * 30)
headers = {
'Origin':'https://www.lagou.com',
'X-Anit-Forge-Code': '0',
'X-Anit-Forge-Token': None,
'X-Requested-With': 'XMLHttpRequest',
'Accept-Encoding': 'gzip, deflate, br',
'Accept-Language': 'h-CN,zh;q=0.9,en;q=0.8',
'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.109 Safari/537.36',
'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8',
'Accept': 'application/json, text/javascript, */*; q=0.01',
'Referer': 'https://www.lagou.com/jobs/list_python?px=default&city=%E6%B7%B1%E5%9C%B3',
'Connection': 'keep-alive',
}
params = {
'px':'default',
'city':'深圳',
'needAddtionalResult':'false'
}
data = {
'first':'true',
'pn':1,
'kd':'python',
}
url_json = 'https://www.lagou.com/jobs/positionAjax.json'
response = requests.post(url=url_json,headers=headers,params=params,cookies=cookies,data=data)
print(response.json())
def main():
parse_list_page()
if __name__ == '__main__':
main()
The reason why I can't get the json as response is the against web scraping rules here is you need to use the first cookie when you send the request.
so when you first send the request you need to save the cookies and then update it to use your second page request. Hope it will helpful for you to do web scraping when you face this problem