chess-project/public/openings

Opening Database

This directory contains the ECO (Encyclopedia of Chess Openings) database files.

Required Files

The following files are required for opening training:

• ecoA.json - ECO codes A00-A99
• ecoB.json - ECO codes B00-B99
• ecoC.json - ECO codes C00-C99
• ecoD.json - ECO codes D00-D99
• ecoE.json - ECO codes E00-E99
• moveIndex.json - Generated move sequence index

File Format

Each ECO file (ecoA-E.json) should be a JSON object mapping FEN positions to opening metadata:

{
  "fen_position": {
    "eco": "A00",
    "name": "Opening Name",
    "moves": "e4 e5 Nf3 Nc6",
    "wikipediaSlug": "opening-name" // optional
  }
}

Setup

Option 1: Docker (Automatic)

When running via Docker, these files should be provided as a volume mount:

docker run -v ./openings:/app/public/openings ghcr.io/stefan-kp/chess-tutor

Option 2: Local Development

1. Obtain ECO database files (ecoA-E.json)
2. Place them in this directory
3. Generate the move index:

npm run build:opening-index

This will create moveIndex.json from the ECO files.

Option 3: Generate from PGN

If you have a PGN database, you can extract ECO codes using chess tools like:

• pgn-extract
• Custom scripts

Notes

• These files are not included in git (too large, ~4MB total)
• Users must provide their own opening database
• Wikipedia integration is optional (see public/wikipedia/README.md)
• The move index is automatically generated during Docker startup