A Chess puzzle generator from Lichess.org match databases using Stockfish to calculate best moves.
I built three simple programs: 1 (Cutter) - Parses the downloaded file from Lichess database (a huge text file of several GBs). The file consists of thousands of PGN games and Cutter is responsible for splitting every game's PGN to a seperate file inside a specified output directory and naming them with unique IDS. 2 (Generator) - The main core that produces puzzle candidates.
- Generator selects and opens a PGN file with a given random id (say 15260) from the output directory.
- Generator then reads the PGN and jumps to also a random position played already in the game (say 15).
- At this point Generator Calls stockfish chess engine and tells it "Hey, here is a chess game at the position (say 15) and white plays now, can you finish the game for me?".
- Note that Generator asks stockfish to play at depth 24 and depth 4 so that we can reach to a checkmate.
- Eventually Generator points to the last 2 to 5 moves in the game that is finished by stockfish.
- Now we have a new puzzle candidate
3 (Storer) - Stores puzzle candidates coming from generator to MongoDB
Storer accepts any puzzle candidate coming from Generator to save it directly into puzzles collection in MongoDB
The backend
The actual program that you need to deploy is backend that will serve all web pages content and do everything related to checking if client solved or seen a puzzle.
The rest three programs we talked about above are like a toolbox for generating/storing puzzles forbackend to be able to serve them.
- notnil/chess library for easier manipulation of chess games in Golang.
- chessboardjs the library that draws chess the board you see in your browser.
Please feel free to fork this repo and to open a new pull request with your own modifications. Contact me at debbech.ahmed@gmail.com