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 Workflow Arena Environment.

This module creates an HTTP server that exposes the WorkflowArenaEnvironment
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
"""

import gradio as gr

try:
    from openenv.core.env_server.http_server import create_app
except Exception as e:  # pragma: no cover
    raise ImportError(
        "openenv is required for the web interface. Install dependencies with '\n    uv sync\n'"
    ) from e

from workflow_arena.models import WorkflowArenaAction, WorkflowArenaObservation
from workflow_arena.server.ui import create_gradio_app
from workflow_arena.server.workflow_arena_environment import WorkflowArenaEnvironment

# Create the app with web interface and README integration
app = create_app(
    WorkflowArenaEnvironment,
    WorkflowArenaAction,
    WorkflowArenaObservation,
    env_name="workflow_arena",
    max_concurrent_envs=1,  # increase this number to allow more concurrent WebSocket sessions
)

# Mount Gradio UI at root — MUST be after all API routes to avoid catchall interference
_gradio_app = create_gradio_app()
app = gr.mount_gradio_app(app, _gradio_app, path="/")


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 workflow_arena.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 workflow_arena.server.app:app --workers 4
    """
    import uvicorn

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


if __name__ == "__main__":
    import argparse

    parser = argparse.ArgumentParser()
    parser.add_argument("--port", type=int, default=8000)
    args = parser.parse_args()
    if args.port == 8000:
        main()
    else:
        main(port=args.port)