Master Python Requests: Web Scraping Basics with GET, POST, and File Saving

Key Topics Covered

How web interaction works Using requests.get and requests.post Response object attributes and methods Opening and saving files in Python

Installing the requests Library

For Windows, run:

<code>pip install -i https://pypi.tuna.tsinghua.edu.cn/simple requests</code>

For Linux, prepend

sudo

if necessary:

<code>sudo pip install -i https://pypi.tuna.tsinghua.edu.cn/simple requests</code>

1. Crawl a Baidu Page

<code># First crawler example – fetch Baidu homepage
import requests
response = requests.get("http://www.baidu.com")
response.encoding = response.apparent_encoding
print("Status code:" + str(response.status_code))
print(response.text)
</code>

2. GET Request Example

<code># GET request to httpbin.org
import requests
response = requests.get("http://httpbin.org/get")
print(response.status_code)
print(response.text)
</code>

3. POST Request Example

<code># POST request to httpbin.org
import requests
response = requests.post("http://httpbin.org/post")
print(response.status_code)
print(response.text)
</code>

4. PUT Request Example

<code># PUT request to httpbin.org
import requests
response = requests.put("http://httpbin.org/put")
print(response.status_code)
print(response.text)
</code>

5. GET with URL Parameters

<code># GET with query string in URL
import requests
response = requests.get("http://httpbin.org/get?name=hezhi&age=20")
print(response.status_code)
print(response.text)
</code>

6. GET with Params Dictionary

<code># GET using params dict
import requests
data = {"name": "hezhi", "age": 20}
response = requests.get("http://httpbin.org/get", params=data)
print(response.status_code)
print(response.text)
</code>

7. POST with Params Dictionary

<code># POST using params dict
import requests
data = {"name": "hezhi", "age": 20}
response = requests.post("http://httpbin.org/post", params=data)
print(response.status_code)
print(response.text)
</code>

8. Bypassing Anti‑Scraping (Example: Zhihu)

<code># First request without headers – likely blocked
import requests
response = requests.get("http://www.zhihu.com")
print("No headers status:" + str(response.status_code))
# Request with a realistic User‑Agent header
headers = {"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.122 Safari/537.36"}
response = requests.get("http://www.zhihu.com", headers=headers)
print("With headers status:" + str(response.status_code))
print(response.text)
</code>

9. Save Crawled HTML to a Local File

<code>import requests
url = "http://www.baidu.com"
response = requests.get(url)
response.encoding = "utf-8"
print("Response type:" + str(type(response)))
print("Status code:" + str(response.status_code))
print("Headers:" + str(response.headers))
print("Content:" + response.text)
# Write to file
with open("D:\\crawler\\baidu.html", "w", encoding="utf-8") as file:
    file.write(response.text)
</code>

10. Download an Image and Save It

<code>import requests
response = requests.get("https://www.baidu.com/img/baidu_jgylogo3.gif")
with open("D:\\crawler\\baidu_logo.gif", "wb") as file:
    file.write(response.content)
</code>