baseimage-tutorial-framework/lib/tfw/event_handler_base.py
2018-03-27 17:49:32 +02:00

78 lines
2.3 KiB
Python

from abc import ABC, abstractmethod
from tfw.networking.serialization import deserialize_all
from tfw.networking.event_handlers.server_connector import ServerConnector
class EventHandlerBase(ABC):
def __init__(self, key):
self.server_connector = ServerConnector()
self.key = key
self.subscriptions = set()
self.subscribe(self.key)
self.subscribe('reset')
self.server_connector.register_callback(self.event_handler_callback)
def event_handler_callback(self, msg_parts):
key, message = deserialize_all(*msg_parts)
response = self.dispatch_handling(key, message)
if response is None: return
self.server_connector.send(key, response)
@abstractmethod
def dispatch_handling(self, key, message):
raise NotImplementedError
def _dispatch_handling(self, key, message):
if key != 'reset': return self.handle_event(key, message)
else: return self.handle_reset(message)
@abstractmethod
def handle_event(self, key, message):
raise NotImplementedError
def handle_reset(self, message):
return None
def cleanup(self):
pass
def message_other(self, key, data):
message = {
'key': key,
'data': data
}
self.server_connector.send(key, message)
def subscribe(self, key):
if key not in self.subscriptions:
self.subscriptions.add(key)
self.server_connector.subscribe(key)
def unsubscribe(self, key):
try:
self.subscriptions.remove(key)
self.server_connector.unsubscribe(key)
except KeyError:
pass
def unsubscribe_all(self):
for sub in self.subscriptions:
self.server_connector.unsubscribe(key=sub)
self.subscriptions.clear()
class TriggerlessEventHandler(EventHandlerBase, ABC):
def dispatch_handling(self, key, message):
return self._dispatch_handling(key, message)
class TriggeredEventHandler(EventHandlerBase, ABC):
def __init__(self, key, trigger):
super().__init__(key)
self.trigger = trigger
def dispatch_handling(self, key, message):
if message.get('trigger') == self.trigger:
return self._dispatch_handling(key, message)