platypush/platypush/event/hook.py

167 lines
5.3 KiB
Python

import copy
import json
import logging
import re
import threading
from platypush.config import Config
from platypush.message.event import Event, EventMatchResult
from platypush.message.request import Request
from platypush.procedure import Procedure
from platypush.utils import get_event_class_by_type, set_thread_name
logger = logging.getLogger(__name__)
def parse(msg):
""" Builds a dict given another dictionary or
a JSON UTF-8 encoded string/bytearray """
if isinstance(msg, bytes) or isinstance(msg, bytearray):
msg = msg.decode('utf-8')
if isinstance(msg, str):
try:
msg = json.loads(msg.strip())
except:
logger.warning('Invalid JSON message: {}'.format(msg))
return None
return msg
class EventCondition(object):
""" Event hook condition class """
def __init__(self, type=Event.__class__, priority=None, **kwargs):
"""
Rule constructor.
Params:
type -- Class of the event to be built
kwargs -- Fields rules as a key-value (e.g. source_button=btn_id
or recognized_phrase='Your phrase')
"""
self.type = type
self.args = {}
self.parsed_args = {}
self.priority = priority
for (key, value) in kwargs.items():
# TODO So far we only allow simple value match. If value is a dict
# instead, we should allow more a sophisticated attribute matching,
# e.g. or conditions, in, and other operators.
self.args[key] = value
@classmethod
def build(cls, rule):
""" Builds a rule given either another EventRule, a dictionary or
a JSON UTF-8 encoded string/bytearray """
if isinstance(rule, cls): return rule
else: rule = parse(rule)
assert isinstance(rule, dict)
type = get_event_class_by_type(
rule.pop('type') if 'type' in rule else 'Event')
args = {}
for (key, value) in rule.items():
args[key] = value
return cls(type=type, **args)
class EventAction(Request):
""" Event hook action class. It is a special type of runnable request
whose fields can be configured later depending on the event context """
def __init__(self, target=None, action=None, **args):
if target is None: target=Config.get('device_id')
args_copy = copy.deepcopy(args)
super().__init__(target=target, action=action, **args_copy)
@classmethod
def build(cls, action):
action = super().parse(action)
action['origin'] = Config.get('device_id')
if 'target' not in action:
action['target'] = action['origin']
token = Config.get('token')
if token:
action['token'] = token
return super().build(action)
class EventHook(object):
""" Event hook class. It consists of one conditionss and
one or multiple actions to be executed """
def __init__(self, name, priority=None, condition=None, actions=[]):
""" Construtor. Takes a name, a EventCondition object and an event action
procedure as input. It may also have a priority attached
as a positive number. If multiple hooks match against an event,
only the ones that have either the maximum match score or the
maximum pre-configured priority will be run. """
self.name = name
self.condition = EventCondition.build(condition or {})
self.actions = actions
self.priority = priority or 0
self.condition.priority = self.priority
@classmethod
def build(cls, name, hook):
""" Builds a rule given either another EventRule, a dictionary or
a JSON UTF-8 encoded string/bytearray """
if isinstance(hook, cls): return hook
else: hook = parse(hook)
assert isinstance(hook, dict)
condition = EventCondition.build(hook['if']) if 'if' in hook else None
actions = []
priority = hook['priority'] if 'priority' in hook else None
condition.priority = priority
if 'then' in hook:
if isinstance(hook['then'], list):
actions = hook['then']
else:
actions = [hook['then']]
actions = Procedure.build(name=name+'__Hook', requests=actions, _async=False)
return cls(name=name, condition=condition, actions=actions, priority=priority)
def matches_event(self, event):
""" Returns an EventMatchResult object containing the information
about the match between the event and this hook """
return event.matches_condition(self.condition)
def run(self, event):
""" Checks the condition of the hook against a particular event and
runs the hook actions if the condition is met """
def _thread_func(result):
set_thread_name('Event-' + self.name)
self.actions.execute(event=event, **result.parsed_args)
result = self.matches_event(event)
token = Config.get('token')
if result.is_match:
logger.info('Running hook {} triggered by an event'.format(self.name))
threading.Thread(target=_thread_func,
name='Event-' + self.name,
args=(result,)).start()
# vim:sw=4:ts=4:et: