iLSP/ilsp/server.py

"""
iLSP main entrypoint.

Starts three services concurrently:
  - pylsp server on TCP :2087  (Python LSP + i80 completions)
  - Bicep proxy  on TCP :2088  (Bicep LS wrapper + LRU modules)
  - Health HTTP  on TCP :2089  (for Consul/Nomad health checks)
"""

import asyncio
import logging
import os
import signal
import subprocess
import sys
import threading

from aiohttp import web

from .python_lsp.catalog import PypiCatalog
from .bicep_lsp.modules import BicepModuleCatalog
from .bicep_lsp.proxy import serve_bicep

logger = logging.getLogger(__name__)

PYTHON_LSP_PORT = int(os.getenv("PYTHON_LSP_PORT", "2087"))
BICEP_LSP_PORT  = int(os.getenv("BICEP_LSP_PORT",  "2088"))
HEALTH_PORT     = int(os.getenv("HEALTH_PORT",     "2089"))


def _serve_python_lsp(port: int) -> None:
    """Start pylsp in TCP server mode; restart on unexpected exit (blocking)."""
    while True:
        proc = subprocess.Popen(
            [sys.executable, "-m", "pylsp", "--tcp", "--host", "0.0.0.0", "--port", str(port)],
        )
        logger.info("Python LSP (pylsp) listening on TCP :%d  PID=%d", port, proc.pid)
        proc.wait()
        logger.warning("pylsp exited (code %s) — restarting", proc.returncode)


async def _health_app() -> web.Application:
    app = web.Application()

    async def health(_: web.Request) -> web.Response:
        return web.json_response({
            "status": "ok",
            "pypi_packages": len(PypiCatalog._packages),
            "bicep_modules": len(BicepModuleCatalog._modules),
        })

    app.router.add_get("/health", health)
    return app


async def main_async() -> None:
    logging.basicConfig(
        level=logging.INFO,
        format="%(asctime)s [%(levelname)s] %(name)s: %(message)s",
    )

    # Pre-warm catalogs before accepting connections
    logger.info("Pre-warming catalogs…")
    BicepModuleCatalog.load()
    await PypiCatalog.start_background_refresh()

    # Both LSP servers run in daemon threads (blocking socket/process loops)
    threading.Thread(target=_serve_python_lsp, args=(PYTHON_LSP_PORT,), daemon=True).start()
    threading.Thread(target=serve_bicep, args=(BICEP_LSP_PORT,), daemon=True).start()

    # Health HTTP server — keeps the process alive via the asyncio event loop
    health_app = await _health_app()
    runner = web.AppRunner(health_app)
    await runner.setup()
    site = web.TCPSite(runner, "0.0.0.0", HEALTH_PORT)
    await site.start()
    logger.info("Health endpoint on http://0.0.0.0:%d/health", HEALTH_PORT)

    # Wait indefinitely; signal handlers in main() will stop the loop
    await asyncio.Event().wait()


def main() -> None:
    loop = asyncio.new_event_loop()
    for sig in (signal.SIGTERM, signal.SIGINT):
        loop.add_signal_handler(sig, loop.stop)
    loop.run_until_complete(main_async())