lookingglass/hyperglass/main.py

"""Start hyperglass."""

# Standard Library
import asyncio
import sys
import typing as t
import logging

# Third Party
import uvicorn

# Local
from .log import LibInterceptHandler, init_logger, enable_file_logging, enable_syslog_logging
from .util import get_node_version
from .constants import MIN_NODE_VERSION, MIN_PYTHON_VERSION, __version__

# Ensure the Python version meets the minimum requirements.
pretty_version = ".".join(tuple(str(v) for v in MIN_PYTHON_VERSION))
if sys.version_info < MIN_PYTHON_VERSION:
    raise RuntimeError(f"Python {pretty_version}+ is required.")

# Ensure the NodeJS version meets the minimum requirements.
node_major, node_minor, node_patch = get_node_version()

if node_major < MIN_NODE_VERSION:
    installed = ".".join(str(v) for v in (node_major, node_minor, node_patch))
    raise RuntimeError(f"NodeJS {MIN_NODE_VERSION!s}+ is required (version {installed} installed)")


# Local
from .util import cpu_count
from .state import use_state
from .settings import Settings

LOG_LEVEL = logging.INFO if Settings.debug is False else logging.DEBUG
logging.basicConfig(handlers=[LibInterceptHandler()], level=0, force=True)
log = init_logger(LOG_LEVEL)


async def build_ui() -> bool:
    """Perform a UI build prior to starting the application."""
    # Local
    from .frontend import build_frontend

    state = use_state()
    await build_frontend(
        dev_mode=Settings.dev_mode,
        dev_url=Settings.dev_url,
        prod_url=Settings.prod_url,
        params=state.ui_params,
        app_path=Settings.app_path,
    )
    return True


def register_all_plugins() -> None:
    """Validate and register configured plugins."""

    # Local
    from .plugins import register_plugin, init_builtin_plugins

    state = use_state()

    # Register built-in plugins.
    init_builtin_plugins()

    failures = ()

    # Register external directive-based plugins (defined in directives).
    for plugin_file, directives in state.devices.directive_plugins().items():
        failures += register_plugin(plugin_file, directives=directives)

    # Register external global/common plugins (defined in config).
    for plugin_file in state.params.common_plugins():
        failures += register_plugin(plugin_file, common=True)

    for failure in failures:
        log.bind(plugin=failure).warning("Invalid hyperglass plugin")


def unregister_all_plugins() -> None:
    """Unregister all plugins."""
    # Local
    from .plugins import InputPluginManager, OutputPluginManager

    for manager in (InputPluginManager, OutputPluginManager):
        manager().reset()


def start(*, log_level: t.Union[str, int], workers: int) -> None:
    """Start hyperglass via ASGI server."""

    register_all_plugins()

    if not Settings.disable_ui:
        asyncio.run(build_ui())

    uvicorn.run(
        app="hyperglass.api:app",
        host=str(Settings.host),
        port=Settings.port,
        workers=workers,
        log_level=log_level,
        log_config={
            "version": 1,
            "disable_existing_loggers": False,
            "formatters": {
                "default": {
                    "()": "uvicorn.logging.DefaultFormatter",
                    "format": "%(message)s",
                },
                "access": {
                    "()": "uvicorn.logging.AccessFormatter",
                    "format": "%(message)s",
                },
            },
            "handlers": {
                "default": {"formatter": "default", "class": "hyperglass.log.LibInterceptHandler"},
                "access": {"formatter": "access", "class": "hyperglass.log.LibInterceptHandler"},
            },
            "loggers": {
                "uvicorn.error": {"level": "ERROR", "handlers": ["default"], "propagate": False},
                "uvicorn.access": {"level": "INFO", "handlers": ["access"], "propagate": False},
            },
        },
    )


def run(workers: int = None):
    """Run hyperglass."""
    # Local
    from .configuration import init_user_config

    try:
        log.debug(repr(Settings))

        state = use_state()
        state.clear()

        init_user_config()

        enable_file_logging(
            directory=state.params.logging.directory,
            max_size=state.params.logging.max_size,
            log_format=state.params.logging.format,
            level=LOG_LEVEL,
        )

        if state.params.logging.syslog is not None:
            enable_syslog_logging(
                host=state.params.logging.syslog.host,
                port=state.params.logging.syslog.port,
            )
        _workers = workers

        if workers is None:
            if Settings.debug:
                _workers = 1
            else:
                _workers = cpu_count(2)

        log.bind(
            version=__version__,
            listening=f"http://{Settings.bind()}",
            workers=_workers,
        ).info(
            "Starting hyperglass",
        )

        start(log_level=LOG_LEVEL, workers=_workers)
        log.bind(version=__version__).critical("Stopping hyperglass")
    except Exception as error:
        log.critical(error)
        # Handle app exceptions.
        if not Settings.dev_mode:
            state = use_state()
            state.clear()
            log.debug("Cleared hyperglass state")
        unregister_all_plugins()
        raise error
    except (SystemExit, BaseException):
        unregister_all_plugins()
        sys.exit(4)


if __name__ == "__main__":
    run()