PHP, Python, Node.js, which one is the most suitable for writing crawlers?

In the data-driven era, web crawlers have become an important tool for obtaining Internet information. Whether it is market analysis, competitor monitoring, or academic research, crawler technology plays an indispensable role. In crawler technology, the use of proxy IP is an important means to bypass the anti-crawler mechanism of the target website and improve the efficiency and success rate of data crawling. Among many programming languages, PHP, Python, and Node.js are often used by developers for crawler development due to their respective characteristics. So, in combination with the use of proxy IP, which language is most suitable for writing crawlers? This article will explore these three options in depth and help you make a wise choice through comparative analysis.

1. The fit between language characteristics and crawler development (combined with proxy IP)

1.1 PHP: Backend king, crawler novice, limited proxy IP support

Advantages:

• Wide application: PHP has a deep foundation in the field of Web development and has rich library and framework support.
• Server environment: Many websites run on the LAMP (Linux, Apache, MySQL, PHP) architecture, and PHP is highly integrated with these environments.

Limitations:

• Weak asynchronous processing: PHP is not as flexible as other languages ​​in asynchronous requests and concurrent processing, which limits the efficiency of crawlers.
• Limited library support: Although there are libraries such as Goutte and Simple HTML DOM Parser, PHP has fewer crawler library options and updates slower than Python.
• Proxy IP processing: The configuration of PHP processing proxy IP is relatively cumbersome, requiring manual setting of cURL options or using third-party libraries, which is less flexible.

1.2 Python: The Swiss Army Knife of the crawler world, with strong proxy IP support

Advantages:

• Strong library support: Libraries such as BeautifulSoup, Scrapy, Selenium, and Requests greatly simplify web page parsing and request sending.
• Easy to learn: Python has concise syntax and a flat learning curve, which is suitable for quick start.
• Powerful data processing: Libraries such as Pandas and NumPy make data cleaning and analysis simple and efficient.
• Proxy IP support: The Requests library provides a simple proxy setting method, and the Scrapy framework has built-in proxy middleware, which can easily realize the rotation and management of proxy IPs.

Limitations:

• Performance bottleneck: Although it can be optimized through multi-threading or multi-process, Python's global interpreter lock (GIL) limits the performance of a single thread.
• Memory management: For large-scale data crawling, Python's memory management needs to be paid attention to to avoid memory leaks.

1.3 Node.js: A leader in asynchronous I/O, flexible proxy IP processing

Advantages:

• Asynchronous non-blocking I/O: Node.js is based on an event-driven architecture, which is very suitable for handling a large number of concurrent requests.
• Superior performance: The single-threaded model plus the efficient execution of the V8 engine make Node.js perform well in handling I/O-intensive tasks.
• Rich ecosystem: Puppeteer, Axios, Cheerio and other libraries provide powerful web crawling and parsing capabilities.
• Proxy IP processing: Node.js has flexible and diverse ways to handle proxy IP. You can use libraries such as Axios to easily set up proxies, or you can combine third-party libraries such as proxy-agent to achieve more complex proxy management.

Limitations:

• Learning curve: For developers who are not familiar with JavaScript, the asynchronous programming model of Node.js may need to be adapted.
• CPU-intensive tasks: Although suitable for I/O-intensive tasks, it is not as efficient as Python or C++ in CPU-intensive tasks.

2. Comparison of actual cases combined with proxy IP

2.1 Simple web crawling using proxy IP

• Python: Use the Requests library to send requests and combine proxy middleware to implement proxy IP rotation.

import requests
from requests.adapters import HTTPAdapter
from requests.packages.urllib3.util.retry import Retry

session = requests.Session()
retries = Retry(total=5, backoff_factor=1, status_forcelist=[500, 502, 503, 504])
adapter = HTTPAdapter(max_retries=retries)
session.mount('http://', adapter)
session.mount('https://', adapter)

proxies = {
    'http': 'http://proxy1.example.com:8080',
    'https': 'http://proxy2.example.com:8080',
}

url = 'http://example.com'
response = session.get(url, proxies=proxies)
print(response.text)

• Node.js: Use the Axios library to send requests and combine the proxy-agent library to set the proxy IP.

const axios = require('axios');
const ProxyAgent = require('proxy-agent');

const proxy = new ProxyAgent('http://proxy.example.com:8080');

axios.get('http://example.com', {
    httpsAgent: proxy,
})
.then(response => {
    console.log(response.data);
})
.catch(error => {
    console.error(error);
});

2.2 Use proxy IP to handle complex scenarios (such as login, JavaScript rendering)

• Python: Combine Selenium and browser driver to use proxy IP for login and other operations.

from selenium import webdriver
from selenium.webdriver.chrome.options import Options

chrome_options = Options()
chrome_options.add_argument('--proxy-server=http://proxy.example.com:8080')

driver = webdriver.Chrome(options=chrome_options)
driver.get('http://example.com/login')
# Perform a login operation...

• Node.js: Use Puppeteer combined with the proxy-chain library to realize automatic selection and switching of proxy chains.

const puppeteer = require('puppeteer');
const ProxyChain = require('proxy-chain');

(async () => {
    const browser = await puppeteer.launch();
    const page = await browser.newPage();

    const proxyChain = new ProxyChain();
    const proxy = await proxyChain.getRandomProxy(); // Get random proxy IP

    await page.setBypassCSP(true); // Bypassing the CSP (Content Security Policy)
    await page.setUserAgent('Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.121 Safari/537.36'); // Setting up the user agent

    const client = await page.target().createCDPSession();
    await client.send('Network.setAcceptInsecureCerts', { enabled: true }); // Allow insecure certificates

    await page.setExtraHTTPHeaders({
        'Proxy-Connection': 'keep-alive',
        'Proxy': `http://${proxy.ip}:${proxy.port}`,
    });

    await page.goto('http://example.com/login');
    // Perform a login operation...

    await browser.close();
})();

3. Summary and suggestions

Combined with the use of proxy IP, we can draw the following conclusions:

• PHP: Although PHP has a deep foundation in the field of Web development, it has limitations in handling proxy IP and concurrent requests, and is not suitable for large-scale or complex crawler tasks.
• Python: With its rich library support, concise syntax and powerful data processing capabilities, Python has become the preferred crawler language for most developers. At the same time, Python is also very flexible and powerful in handling proxy IPs, and can easily implement both simple proxy settings and complex proxy management.
• Node.js: For complex crawlers that need to handle a large number of concurrent requests or need to process JavaScript rendered pages, Node.js is a very good choice with its asynchronous I/O advantages. At the same time, Node.js also performs well in handling proxy IPs, providing a variety of flexible ways to set up and manage proxy IPs.

In summary, which language to choose to develop crawlers and combine the use of proxy IPs depends on your specific needs, team technology stack, and personal preferences. I hope this article can help you make the decision that best suits your project.

Web crawler proxy ip