Search service for lichess.org

"Keep elasticsearch threads out of your web facing app, kids" -- W. Churchill

Architecture

This project is organized into several modules:

• app - Search HTTP API service
• core - Core domain models and types
• elastic - Elasticsearch client wrapper
• lila-mongo - MongoDB repository abstractions and change stream support
• lila-game-export - Standalone CLI tool for exporting game data to CSV
• ingestor-core - Core indexing logic and repository implementations
• ingestor-app - Indexing service (watches MongoDB changes and updates Elasticsearch)
• ingestor-cli - CLI tool for batch indexing operations
• client - HTTP client for the search API
• e2e - End-to-end integration tests

Development

Start sbt

Start sbt:

sbt

Inside sbt console

Start server:

app/run

Run tests:

test

Run code format and auto code refactor with scalafmt & scalafix:

prepare

Start ingestor service:

ingestor-app/run

Start ingestor CLI tool:

ingestor-cli/run --help

Start game export CLI tool:

lila-game-export/run --help

CLI Tools

Index commands (ingestor-cli)

# Index all documents for specific index (batch mode)
sbt 'ingestor-cli/run index --index team --since 0'

# Index all documents for all indexes (batch mode)
sbt 'ingestor-cli/run index --all --since 0'

# Index with time range
sbt 'ingestor-cli/run index --index game --since 1704067200 --until 1704153600'

# Watch mode: continuously index documents as they arrive
sbt 'ingestor-cli/run index --index game --since 1704067200 --watch'

# Watch mode for all indexes
sbt 'ingestor-cli/run index --all --since 1704067200 --watch'

Export commands (lila-game-export)

The lila-game-export module is a standalone CLI tool for exporting game data from MongoDB to CSV format.

# Batch export: export games from a time range to CSV
sbt 'lila-game-export/run --mongo-uri mongodb://localhost:27017 --output games.csv --since 1704067200 --until 1704153600'

# Watch mode: continuously export games as they arrive
sbt 'lila-game-export/run --mongo-uri mongodb://localhost:27017 --output games.csv --since 1704067200 --watch'

# With custom MongoDB database
sbt 'lila-game-export/run --mongo-uri mongodb://localhost:27017 --mongo-database lichess-prod --output games.csv --since 0'

# With custom batch settings
sbt 'lila-game-export/run --mongo-uri mongodb://localhost:27017 --batch-size 5000 --time-windows 10 --output games.csv --since 0'

# Using environment variables
export MONGO_URI=mongodb://localhost:27017
export MONGO_DATABASE=lichess
sbt 'lila-game-export/run --output games.csv --since 0'

Available options:

• --mongo-uri - MongoDB connection URI (or use MONGO_URI env var)
• --mongo-database - Database name (default: lichess, or use MONGO_DATABASE env var)
• --batch-size - Batch size for MongoDB operations (default: 1000)
• --time-windows - Time window in seconds for batching events (default: 5)
• --output - Output CSV file path (required)
• --since - Start timestamp in epoch seconds (required)
• --until - End timestamp in epoch seconds (default: now)
• --watch - Watch change stream continuously
• --format - Export format (only support csv)

release

sbt release with-defaults