baseimage-tutorial-framework/lib/tfw/components/process_managing_event_handler.py

from tfw.event_handler_base import TriggerlessEventHandler
from tfw.components.mixins import SupervisorMixin
from tfw.networking.event_handlers.server_connector import ServerUplinkConnector
from tfw.config.logs import logging
log = logging.getLogger(__name__)


class ProcessManager(SupervisorMixin):
    def __init__(self, supervisor_process_name):
        self.process_name = supervisor_process_name
        self.commands = {'start': self.start_process,
                         'stop': self.stop_process,
                         'restart': self.restart_process}

    def __call__(self, command):
        self.commands[command]()


class ProcessManagingEventHandler(TriggerlessEventHandler):
    def __init__(self, key, supervisor_process_name):
        super().__init__(key)
        self.key = key
        self.processmanager = ProcessManager(supervisor_process_name)
        self.uplink = ServerUplinkConnector()

    def handle_event(self, key, data_json):
        self.processmanager(data_json['data']['command'])
        self.uplink.send(self.key, {'key': self.key})