Boardgame Price Aggregator

A web application that aggregates board game prices from multiple game stores in Chile.

The goal is to provide an easy way to browse, compare, and track prices.

Check the live website!

Features

• Homepage sections:
  • New deals
  • Best deals
  • Most viewed
  • Top N BGG deals
• Board game search:
  • Search boar games by name using the BGG database
• BGG integration
• Board game details:
  • Metadata powered by the BGG API
  • List of available listings
  • Price history chart
• Contact messages:
  • General contact form
  • Board game error reports
• Administrative views:
  • Upload listing data via CSV
  • Manual listing matching
  • Manage contact messages
• Listing - Board game matching:
  • Groups listings under a common board game to allow comparisons
  • Programmatically identifies which board game a listing represents

Notable Components

Listing - BoardGame matching

Handles the logic for programmatically identifying which board game a given listing refers to.

It’s implemented using the following techniques:

• String normalization
• Trigram decomposition
• Jaccard index similarity
• BGG API /search calls
• Weighted average of name similarity and BGG rank (to resolve name collisions)

Relevant code:

• app/services/identification/listing_identifier.rb
• app/services/search_method/search_result_ranker.rb

BoardGameGeek API integration

Wraps calls to the BGG API to fetch metadata; designed to eventually be extracted into a standalone gem.

Primarily responsible for parsing XML responses, with a thin cache layer.

Relevant code: lib/bgg/

Price history & charts

Thanks to the listing identification process, all listings for the same board game can be compared simultaneously.

Having a price history chart allows users to spot fake deals or overpriced items at a glance.

Charts are built using the chartkick gem.

Relevant code:

• app/controllers/boardgames_controller.rb
• app/views/boardgames/show.html.erb
• app/views/boardgames/_price_chart.html.erb.

CSV ingestion

The application is intentionally built without web scraping functionality to maintain separation of concerns.

Listing data is uploaded via an HTML form and CSV files.

Relevant code:

• app/services/listing_csv_import_service.rb
• app/controllers/admin/uploads_controller.rb

Admin functionality.

Admin dashboard for general executive tasks:

• Upload CSV data
• Highlight possible web scraping errors
• Listing matching:
  • Manually identify or unidentify
  • Manually mark as non-board game

Relevant code:

• app/controllers/admin
• app/views/admin.

Technical Notes

• Built with Ruby on Rails
• Uses PostgreSQL as the database engine
• Runs inside Docker
• Deployed using Docker Compose:
  • Rails application container
  • PostgreSQL container
  • Background job worker container (currently disabled; workload is minimal, so the app can run using SOLID_QUEUE_IN_PUMA=true)
  • Nginx container (currently disabled; Nginx runs on the host to allow the host’s fail2ban service to access its logs)
• Deployed on a single DigitalOcean droplet VPS

Roadmap

• Automate web scraping execution
  • Decide on an upload API (REST endpoint vs mounting a Docker directory and reading CSV files)
  • Implement proper observability, logging, and alerts to catch web scraping issues
• Better UI/UX
  • Allow users to filter by category, mechanics, author, year, etc.
  • Show related or similar items on boardgames#show pages
• Improve BGG metadata integration
  • Mark board games as Base Game or Expansion
  • Add support for RPGG items
• Extract BGG API integration into a standalone gem
• Implement ML/AI solutions for:
  • Listing name normalization
  • Listing - Board game matching
  • Non-board game listing detection

Setup

Environment Variables (.env)

In addition to the standard Rails and PostgreSQL environment variables, the project requires:

• Admin user seed:
  • ADMIN_EMAIL
  • ADMIN_PASSWORD
• BGG daily rank CSV download (requires user sign-in):
  • BGG_USERNAME
  • BGG_PASSWORD

Acknowledgements

Inspired in websites like solotodo and knasta.

License