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Mastering HTTP Connections: Comprehensive Guide on How to Use cURL in Python

cURL is a widely used HTTP client tool and a C library (libcurl), plays a pivotal role in web development and data extraction processes.  It can also be harnessed in Python through numerous wrapper libraries, enhancing its utility in scripting and automation tasks. Leveraging a web scraping API in conjunction with cURL functionality in Python can dramatically expand your capabilities in handling web data. This approach allows for the seamless integration of complex web scraping and data processing tasks, ensuring efficient and effective data collection and manipulation strategies.

The most commonly used library that incorporates libcurl in Python is pycurl. Here’s an example of its application:

import pycurl
from io import BytesIO

# Set the URL you want to fetch
url = 'https://www.example.com/'

# Create a new Curl object
curl = pycurl.Curl()

# Set the URL and other options
curl.setopt(pycurl.URL, url)
# Follow redirects
curl.setopt(pycurl.FOLLOWLOCATION, 1)
# Set the user agent
curl.setopt(pycurl.USERAGENT, 'Mozilla/5.0')

# Create a buffer to store the response and add it as result target
buffer = BytesIO()
curl.setopt(pycurl.WRITEFUNCTION, buffer.write)

# Perform the request
curl.perform()

# Get the response code and content
response_code = curl.getinfo(pycurl.RESPONSE_CODE)
response_content = buffer.getvalue().decode('UTF-8')

# Print the response
print(f'Response code: {response_code}')
print(f'Response content: {response_content}')

# Clean up
curl.close()
buffer.close()

When compared to other libraries like requests and httpx, pycurl is quite low-level and can be challenging to use. However, it provides access to many advanced features like HTTP3 support that other libraries lack.

pyCurl does not support asynchronous requests, which means it cannot be used in asynchronous web scraping, though it can still be used with threads. For more details, see mixing sync code using asyncio.to_thread().