python爬虫--requests模块

requests模块

• 安装 :pip install requests
• 作用：就是用来模拟浏览器上网的。
• 特点：简单，高效
• 其他的爬虫模块(old): urllib模块

一. 使用

• requests模块的使用流程：
  • 指定url
  • 发起请求
  • 获取响应数据
  • 持久化存储

#爬取搜狗首页的页面数据
import requests

#1指定url
url = 'https://www.sogou.com/'

#2.发起请求
response = requests.get(url=url)

#3获取响应数据
page_text = response.text #text返回的是字符串类型的数据

#持久化存储
with open('./sogou.html','w',encoding='utf-8') as fp:
    fp.write(page_text)
print('over!')

1.get请求使用

• 处理get请求的参数
• 需求：网页采集器
• 反爬机制：UA检测
• 反反爬策略：UA伪装

示例:1

import requests
wd = input('enter a word:')
url = 'https://www.sogou.com/web'

#参数的封装
param = {
    'query':wd
}

#UA伪装
headers = {
    'User-Agent':'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36'
}
response = requests.get(url=url,params=param,headers=headers)

#手动修改响应数据的编码
response.encoding = 'utf-8'
page_text = response.text
fileName = wd + '.html'
with open(fileName,'w',encoding='utf-8') as fp:
    fp.write(page_text)
print(fileName,'爬取成功！！！')

2.post请求使用

示例2:

#破解百度翻译
url = 'https://fanyi.baidu.com/sug'
word = input('enter a English word:')
#请求参数的封装
data = {
    'kw':word
}
#UA伪装
headers = {
    'User-Agent':'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36'
}
response = requests.post(url=url,data=data,headers=headers)
#text:字符串  json():对象
obj_json = response.json()

print(obj_json)

示例3:

#爬取任意城市对应的肯德基餐厅的位置信息
#动态加载的数据
city = input('enter a cityName:')
url = 'http://www.kfc.com.cn/kfccda/ashx/GetStoreList.ashx?op=keyword'
data = {
    "cname": "",
    "pid": "",
    "keyword": city,
    "pageIndex": "2",
    "pageSize": "10",
}
#UA伪装
headers = {
    'User-Agent':'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36'
}
response = requests.post(url=url,headers=headers,data=data)

json_text = response.text

print(json_text)