MicroUCI Chess Development Server

MicroUCI Chess Development Server is a lightweight HTTP server / web application designed to aid in the development and testing of chess engines through a web interface. It supports UCI-compatible chess engines, such as Stockfish or Leela Chess Zero, and acts as a bridge between the web interface and the chess engine, allowing developers to test their engines directly from their browser.

Installation

1. Clone the repository to your local environment.
2. Install a UCI-compatible chess engine (e.g., Stockfish, Leela Chess Zero) and ensure it is accessible via your system PATH.
3. Configure the server by creating a config.yaml file with your desired settings. Below is a sample configuration:

    # Path to the UCI engine executable
    engine_path: "lc0"
   
    # Address and port for the server to listen on
    server_addr: ":8080"
   
    # Time allocated for the engine to calculate its move in milliseconds
    move_time: 100

4. Build the application

   go build

5. Run the server

   ./microuci

6. Navigate to localhost:8080 in your browser.

Configuration Format

The configuration for the MicroUCI Chess Development Server is specified in a config.yaml file. This file allows you to customize various aspects of the server and the chess engine it interfaces with. Below is a detailed description of the configuration options available:

• engine_path: Specifies the path to the UCI-compatible chess engine executable. This should be set to the location of your chess engine binary, such as "stockfish" or "lc0".

• server_addr: Defines the address and port on which the server will listen for incoming HTTP requests. The default value is ":8080", which means the server will listen on all available network interfaces on port 8080.

• move_time: Sets the time allocated for the chess engine to calculate its move, specified in milliseconds.

• uci_options: A map of additional options that can be set for the UCI engine. These options are specific to the engine being used and can include settings such as:

  • hash: The size of the hash table in megabytes, which the engine uses for storing positions.
  • ponder: A boolean option to enable or disable pondering, which allows the engine to think during the opponent's turn.
  • threads: The number of CPU threads the engine should use for computation.
  • WeightsFile: Path to a weights file, which is specific to engines like Leela Chess Zero that use neural networks.

API Reference

The MicroUCI Chess Development Server provides several HTTP endpoints to interact with the chess engine. Below is a list of available endpoints and their functionalities:

GET /new

• Description: Initializes a new chess game.
• Response: Returns a JSON object with a message indicating that a new game has started.

GET /move

• Description: Makes a move in the current game.
• Parameters:
  • uci: (optional) The move in UCI format.
  • san: (optional) The move in SAN format.
• Response: Returns a JSON object containing the best move calculated by the engine, the current FEN string, legal moves, engine info, and the PGN of the game.

GET /show

• Description: Displays the current board position in ASCII format.
• Response: Returns a plain text representation of the current board position.

GET /fen

• Description: Retrieves the current position in FEN format along with legal moves and PGN.
• Response: Returns a JSON object containing the FEN string, legal moves, and the PGN of the game.

GET /info

• Description: Provides information about the UCI engine and its options.
• Response: Returns a JSON object with the engine's information and available options.

GET /img

• Description: Retrieves an image of a chess piece.
• Parameters:
  • piece: The name of the piece to retrieve.
• Response: Returns a PNG image of the specified chess piece.