AI assistants, such as ChatGPT and Gemini, would’ve never seen the light of day if it weren’t for the huge body of content that these large language models (LLM) were trained on. A significant amount of this content was acquired through the practice of web scraping.
Not only is web scraping useful for training LLMs, but it can also be used for market analysis, price monitoring, and lead generation.
In this article, you’ll compare two popular tools that are used for web scraping: Scrapy and Puppeteer. Scrapy was designed with web scraping in mind, while Puppeteer is a headless browser emulation framework. It’s worth noting that Scrapy was built for Python, while Puppeteer was developed for Node.js. However, there is a Python port available for Puppeteer called pyppeteer.
Throughout this article, you’ll look at each tool’s ease of use, speed of scraping, features, community support, and use cases. By the end of the article, you’ll have a better idea of which tool may be right for you.
Scrapy vs. Puppeteer: Ease of Use
Scrapy is a complete framework that requires knowledge of the classes before you can get started. For example, the core class of Scrapy is a spider, which is a definition of what pages should be crawled and which elements should be parsed. There’s a multitude of other classes, including item, selector, and ItemLoader. And all these classes are best used within the concept of a pipeline.
Although the documentation is extensive, using Scrapy requires some upfront knowledge about the way your code should be structured.
To install Scrapy and create a project structure, you can run the following commands in your terminal:
pip install scrapy
scrapy startproject <project_name>
In comparison, Puppeteer simply offers various functions that can be used for manipulating a headless browser: navigate to a website and select or click elements. It’s up to the developer to structure their code properly.
Getting started with Puppeteer takes only a single command away. No specific project structure needs to be created:
npm install puppeteerIn comparison, Puppeteer simply offers various functions that can be used for manipulating a headless browser: navigate to a website and select or click elements. It’s up to the developer to structure their code properly.
Getting started with Puppeteer takes only a single command away. No specific project structure needs to be created:
npm install puppeteer
Scrapy vs. Puppeteer: Performance
Due to their different approaches, Scrapy and Puppeteer differ significantly in terms of scraping speed.
Scrapy sends an HTTP request to a server and processes the response for that single (mostly HTML) resource. This approach allows Scrapy to process dozens of pages asynchronously, traverse the DOM, and select the required elements, all at subsecond latency.
Puppeteer takes a completely different approach. As a browser emulation software, it navigates to a website, downloads all the resources (such as images or external scripts), and loads them into the browser’s memory. Asynchronously running multiple headless browsers isn’t recommended as it could put a heavy strain on a device’s performance, further hindering the scraping procedure. Clearly, Puppeteer doesn’t excel at speed.
Scrapy vs. Puppeteer: Features
Scrapy has three notable features—Scrapy shell, middleware, and contracts:
- The Scrapy shell runs an interactive session and can be used to debug element selectors.
- Scrapy supports integration with various other libraries through its middleware class to tackle specific use cases. For example, Chompjs can be used for parsing JavaScript objects, and Playwright for Python can be used within a spider to navigate websites with dynamically loaded content. These functionalities can easily be integrated into Scrapy through the use of the Scrapy middleware class.
- A Scrapy spider can be constrained with a contract, which is a kind of test to determine if the page a spider loads is in line with expectations. For example, an individual can add a contract to test if a page loads fast enough or contains the required number of elements. It’s also possible to develop custom contracts.
Scrapy also boasts a rich set of features to avoid getting blocked by antibot measures. This includes integrating with proxy servers and rotating browser fingerprints (such as User-Agent).
Puppeteer also has some unique functionalities, including screenshot generation, interactivity, and timeline tracing. Since Puppeteer emulates a complete browser, it renders a web page in its entirety. The result is that Puppeteer can translate the rendered page into a screenshot or even into a PDF.
Puppeteer has no problems with rendering dynamic websites and offers the necessary tools to interact with them. By selecting elements, inserting text, and clicking buttons, Puppeteer can even be used to submit forms. This is one of the main reasons for choosing Puppeteer (more on this later).
Puppeteer also supports rotating proxies, and its browser fingerprint can be manipulated by tweaking browser parameters individually. If manually tweaking these parameters is too hard, Puppeteer also has a plugin known as stealth, which makes things easier.
Another interesting feature of Puppeteer is its ability to generate web performance audits. Not only is this useful for testing websites, but it can also be used to identify if the website’s server is throttling your spider:
Scrapy vs. Puppeteer: Community Support
As of February 28, 2024, Scrapy has 1,800 watchers and 52,000 stars on GitHub, with commits from various users happening on a nearly daily basis. Scrapy also has a Reddit community that receives several questions per week, and most get half a dozen answers. If you want even more support, Scrapy has a Discord community and is on Stack Overflow, where over 17,000 Scrapy-related questions have been asked.
In contrast, on GitHub, Puppeteer has fewer watchers (1,200) than Scrapy but has more stars (86,000) and daily commits from various contributors. Puppeteer doesn’t have officially supported communities on Reddit or Discord, but over 8,000 Puppeteer-related questions have been asked on Stack Overflow.
Finally, both Puppeteer and Scrapy have a rich set of community-supported plugins or extensions tailored to specific use cases; for example, to integrate Scrapy with headless browsers and to parse dynamic websites.
Scrapy and Puppeteer Use Cases
So far, in this article, you’ve briefly learned about two use cases and how both tools excel at one or the other: scraping large volumes of static data or accessing dynamically loaded data.
Scraping Large Volumes of Static Web Pages
Because Scrapy simply loads the DOM of a target page, it’s your best choice for large-scale scraping projects with data spread across thousands of pages. Because it can operate asynchronously and doesn’t download additional resources, Scrapy can visit multiple websites at the same time, easily scraping dozens of websites at sub-second latency. For example, if you want to download all the comments from the comments section of all the articles on your favorite news website, Scrapy excels.
In contrast, if you wanted Puppeteer to do this same thing, it can’t load only the individual page completely in the browser. It would also download additional images, scripts, and other embedded objects to render the website completely, as is expected of a tool that was designed to test web applications. This creates a lot of overhead that is often not required when the list of pages contains solely static content and would be much slower than using Scrapy.
Scraping Content from Dynamic Web Pages
Today, the web isn’t focused only on rendering information on web pages but also on interactivity. Many websites have become graphical user interfaces (GUIs), which means the following scenarios can happen:
- Comments are hidden behind a Read comments button that appends them to the page.
- Content is grouped in and behind tabs.
- Articles are hidden behind paywalls and require logging in and submitting CAPTCHAs.
- Some websites exist on a single page and show content that is determined by the user’s browsing behavior.
Scrapy can’t handle this kind of content out of the box. Scraping dynamic websites would require integrating with middleware, such as Splash, or using a browser emulation tool, such as Playwright or Selenium.
This use case is where Puppeteer truly outshines Scrapy. Its headless browser paradigm enables it to fully load web pages, and its JavaScript code delivers the interactivity of a website. Instead of trying to access certain HTML elements that haven’t been loaded yet, Puppeteer can interact with the web application, wait for the HTML elements to load (and poll for their existence), select them, and download their contents when they become available.
It’s important to note that Scrapy and Puppeteer can integrate by using the scrapy-pyppeteer module. This module may be helpful if you’re convinced of Scrapy’s framework but need a headless browser to access dynamically loaded content.
Conclusion
Scrapy and Puppeteer are tools that follow completely different paradigms and have even been designed with different goals in mind. However, they can both be used for scraping web content. Due to these differences in approach, Scrapy is your go-to solution for scraping enormous volumes of data, while Puppeteer is the best choice for navigating websites that render certain content after specific user interactivity.
However, these tools also have commonalities. Their communities are somewhat comparable, and they’re more or less equal when it comes to ease of use. They also have common features, such as browser fingerprint and proxy rotation.
If you’re looking for a tool stack to industrialize your scraping efforts, consider Bright Data, which offers millions of proxy servers, scraping APIs, a browser specifically made for scraping, and readily accessible data sets. Bright Data also has a lot of great web scraping documentation. For instance, you can learn more about the Puppeteer web scraping and explore integrations with both Puppeteer and Scrapy.
