Scraping LEGO for Fun: A Hacky Dive into Dynamic Data Extraction

Peter Lodri

Thursday 15:00 in Helium3

Advanced Web Scraping: From LEGO to Production

Today's web landscape is teeming with JavaScript-heavy content, complex layouts, and sometimes opaque data structures. But what if you could reliably scrape rich product information—images, specs, descriptions—from modern e-commerce sites without hitting constant roadblocks? This session tackles advanced scraping with Python, Scrapy, and Playwright, exemplified by data extraction from LEGO product pages. We'll explore a "grey hat" perspective—applying a slightly "hacky" mindset—while stressing practical ethics, performance considerations, and compliance with site policies.

Outline

1. Introduction: The Hacky Spirit vs. Ethical Constraints

  • Why scrape LEGO?
  • Setting boundaries: terms of service, rate limiting, and disclaimers
  • When "scraping for fun" crosses into potential legal pitfalls

2. Scraping Tech Stack Overview

  • Scrapy for structured crawling and item pipelines
  • Playwright for rendering JavaScript and handling dynamic elements
  • Comparison to traditional HTML-only approaches
  • Project structure, environment setup, and practical tips

3. Spiders in Action

  • Product Spider: Extracting core product data (ID, name, specifications, multiple images)
  • Gallery Spider: Navigating hidden galleries, handling tricky JS-based carousels, and filtering unwanted images
  • Ensuring consistent output (JSON or database ingestion)

4. Model Context Protocol (MCP) Integration

  • Definition: Leveraging specialized helper servers for orchestrating data fetching, refining selectors, and automating debugging
  • Chaining Large Language Models: Code suggestions, auto-generation of selectors, and reactive error handling
  • Example workflow: "Broken selector? Ask the MCP server for an LLM-aided fix"

5. Performance & Scale

  • Polite but robust concurrency: balancing speed and TOS compliance
  • Handling large link lists, incremental updates, and site changes
  • Monitoring and logging for reliability, debugging, and optimization

6. Ethics & Privacy

  • Respecting site ownership, disclaimers, and usage limits
  • Storing scraped data securely and avoiding personal information
  • A discussion of "grey hat" territory: testing site vulnerabilities without exploiting them

7. Use Cases & Extensions

  • Research software engineering: building reproducible data sets
  • Robotics and embedded: offline or partial data ingestion for classification or motion planning
  • Future directions: advanced concurrency, containerization, and HPC

8. Demo & Q&A

  • Live snippet showing an MCP-powered spider reacting to a changed DOM structure
  • Q&A session on bridging the gap between hackery and best practices

Key Takeaways

  • Techniques for scraping dynamic, JS-heavy sites using Python, Scrapy, and Playwright
  • Practical "hacky" methods balanced by responsible, 'ethical approaches'
  • Introduction to Model Context Protocol servers for automated code refinement
  • Scalable patterns for data handling, from small tests to large-scale deployments

Whether you're a data engineer, hobbyist, or researcher, this talk provides a robust (and slightly subversive) recipe for capturing essential data from the wild world of modern websites—without crossing into unethical or unlawful territory.

Peter Lodri

Hacker-maker, specialising in system infiltration and enhancement. Expert in reverse engineering, distributed systems architecture, and AI integration. Proven track record in high-stakes technical operations and system security.