Python爬虫快速上手教程

1 这个是什么

       整理Python中requests常用的API

2 代码

from bs4 import BeautifulSoup
import requests
import re

# 使用requests进行网络求解，用BeautifulSoup处理html网页
s_url = "https://www.baidu.com"
o_header = {
        'Accept': 'image/webp,image/apng,image/*,*/*;q=0.8',
        'Accept-Encoding': 'gzip, deflate',
        'Accept-Language': 'en-US,en;q=0.8',
        'Connection': 'keep-alive',
        'Referer': 'https://www.baidu.com',
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.102 Safari/537.36'
}
n_timeout = 36 # 设置超时秒数

'''
处理资源文件, url返回一个图片、音频、视频
'''
s_local_url = "img.jpg"
resp_stream = requests.get(s_local_url, stream=True, headers=o_header, timeout=n_timeout) #进行图片下载   

with open(s_local_url, 'wb', buffering = 1024) as fp:
    fp.write(resp_stream.content)
    fp.flush()          

'''
处理html, url返回一个网页
'''
# 使用get命令得到请求
resp = requests.get(s_url, headers=o_header, timeout= n_timeout)

# 得到明显的编码
resp.encoding = resp.apparent_encoding

# 字符串html转为soup
soup__html = BeautifulSoup(resp, "lxml")   

# 找到所有的id属性为abc的h
soup__h = soup__html.find("a", id="h")
print(soup__h.text)

# 找到所有的class属性为abc的<img>
soup__img_s = soup__html.find("img", class_="abc")
for soup__img in soup__img_s:
    print(soup__img["src"], soup__img.text)

# 找到所有的abc属性为opq的a
soup__a = soup__html.find("a", attrs= {"abc" :"opq"})
print(soup__a.text)

# 找到所有的abc属性为opq 1, opq 2的a (正则找)
soup__a = soup__html.find("a", attrs= {"abc" :re.compile(r"opq(\s\w+)?")})
print(soup__a.text)