When developing a RAG chatbot that uses a knowledge base to source its responses, it is often necessary to retrieve data directly from web pages. For this, we need a suitable tool: a "scraper." But what exactly is a scraper? Let's explore the specifics of two popular scrapers, Cheerio and Puppeteer, to understand which might be best suited to your needs.

What is a web scraper ?

A webscraper is a tool or software designed to extract data from websites. This extraction is done by analyzing the content of web pages to then retrieve specific information in an automated manner.

Two popular scraping tools: Cheerio and Puppeteer

Cheerio :

• Specifically designed for web scraping.

• Acts as a DOM parser, capable of processing HTML and XML files.

• Does not load websites like a browser, making it extremely fast.

• Uses a syntax similar to jQuery, allowing easy selection of elements via CSS/XPath selectors.

Puppeteer :

• Oriented towards browser automation and testing.

• Can execute JavaScript, which is essential for scraping dynamic pages such as single-page applications (SPAs).

• Capable of interacting with sites, including content behind login forms or scripts.

• Slower compared to Cheerio as it simulates a complete browser.

Detailed Comparison

• Design: Cheerio is designed for fast scraping without rendering, while Puppeteer is used for full browser automation.

• Capability: Cheerio allows quick static analysis, whereas Puppeteer handles dynamic interaction and scraping.

• Usage: Cheerio is simple to use with CSS selectors, but Puppeteer, due to its numerous features, requires asynchronous management and has a more complex learning curve.

• Performance: Cheerio is extremely fast compared to Puppeteer, which is slower but more powerful for certain tasks.

  
  

Conclusion: When to use Cheerio or Puppeteer?

When speed and simplicity are paramount and the data to be scraped is static, Cheerio is often the best choice. Start with this tool by fine-tuning your selectors to exclude unwanted elements.

If you encounter obstacles such as blocks by remote servers or need to extract data from pages requiring complex interactions (like navigating forms or dynamically loading content), Puppeteer is preferable. Although slower, it offers a simulation closer to a real user, thus increasing the chances of bypassing anti-scraping protections such as WAF (Web Application Firewall).

The Smartly.ai platform natively integrates these two powerful scraping tools to enrich your projects. Feel free to contact us for a personalized demonstration.