server/app.py

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree.

"""
FastAPI application for the Maze Env Environment.

This module creates an HTTP server that exposes the MazeEnvironment
over HTTP and WebSocket endpoints, compatible with EnvClient.

Endpoints:
    - POST /reset: Reset the environment
    - POST /step: Execute an action
    - GET /state: Get current environment state
    - GET /schema: Get action/observation schemas
    - WS /ws: WebSocket endpoint for persistent sessions

Usage:
    # Development (with auto-reload):
    uvicorn server.app:app --reload --host 0.0.0.0 --port 8000

    # Production:
    uvicorn server.app:app --host 0.0.0.0 --port 8000 --workers 4

    # Or run directly:
    python -m server.app
"""

# Support both in-repo and standalone imports
try:
    # In-repo imports (when running from OpenEnv repository)
    from openenv.core.env_server.http_server import create_app
    from ..models import MazeAction, MazeObservation
    from .maze_env_environment import MazeEnvironment
except ImportError:
    # Standalone imports (when environment is standalone with openenv-core from pip)
    from openenv_core.env_server.http_server import create_app
    from models import MazeAction, MazeObservation
    from server.maze_env_environment import MazeEnvironment


# Create the app with web interface and README integration
app = create_app(
    MazeEnvironment,
    MazeAction,
    MazeObservation,
    env_name="maze_env",
    max_concurrent_envs=1,  # increase this number to allow more concurrent WebSocket sessions
)


def main(host: str = "0.0.0.0", port: int = 8000):
    """
    Entry point for direct execution via uv run or python -m.

    This function enables running the server without Docker:
        uv run --project . server
        uv run --project . server --port 8001
        python -m maze_env.server.app

    Args:
        host: Host address to bind to (default: "0.0.0.0")
        port: Port number to listen on (default: 8000)

    For production deployments, consider using uvicorn directly with
    multiple workers:
        uvicorn maze_env.server.app:app --workers 4
    """
    import uvicorn

    uvicorn.run(app, host=host, port=port)


if __name__ == "__main__":
    main()