Mercurial > libervia-backend
view sat/tools/trigger.py @ 3372:5d926c7b0d99
plugin app manager: first draft:
/!\ new optional dependency: pyyaml
this plugin manage the life cycle of external applications. Application handlers register
to it.
Data needed to launch an application as set in YAML files. Local data types are used to
get values directly from SàT:
- !sat_conf to retrieve a configuration value
- !sat_generate_pwd to generate a password
- !sat_param for parameters specified a launch
Data can be exposed when an instance is launched, this can be used to specify the port
(notably the one used for web), or a generated password.
author | Goffi <goffi@goffi.org> |
---|---|
date | Mon, 28 Sep 2020 21:10:30 +0200 |
parents | 559a625a236b |
children | be6d91572633 |
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#!/usr/bin/env python3 # SAT: a jabber client # Copyright (C) 2009-2020 Jérôme Poisson (goffi@goffi.org) # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Affero General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU Affero General Public License for more details. # You should have received a copy of the GNU Affero General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. """Misc usefull classes""" from sat.core.i18n import _ from sat.core.log import getLogger log = getLogger(__name__) class TriggerException(Exception): pass class SkipOtherTriggers(Exception): """ Exception to raise if normal behaviour must be followed instead of following triggers list """ pass class TriggerManager(object): """This class manage triggers: code which interact to change the behaviour of SàT""" try: # FIXME: to be removed when a better solution is found MIN_PRIORITY = float("-inf") MAX_PRIORITY = float("+inf") except: # XXX: Pyjamas will bug if you specify ValueError here # Pyjamas uses the JS Float class MIN_PRIORITY = Number.NEGATIVE_INFINITY MAX_PRIORITY = Number.POSITIVE_INFINITY def __init__(self): self.__triggers = {} def add(self, point_name, callback, priority=0): """Add a trigger to a point @param point_name: name of the point when the trigger should be run @param callback: method to call at the trigger point @param priority: callback will be called in priority order, biggest first """ if point_name not in self.__triggers: self.__triggers[point_name] = [] if priority != 0 and priority in [ trigger_tuple[0] for trigger_tuple in self.__triggers[point_name] ]: if priority in (self.MIN_PRIORITY, self.MAX_PRIORITY): log.warning(_("There is already a bound priority [%s]") % point_name) else: log.debug( _("There is already a trigger with the same priority [%s]") % point_name ) self.__triggers[point_name].append((priority, callback)) self.__triggers[point_name].sort( key=lambda trigger_tuple: trigger_tuple[0], reverse=True ) def remove(self, point_name, callback): """Remove a trigger from a point @param point_name: name of the point when the trigger should be run @param callback: method to remove, must exists in the trigger point """ for trigger_tuple in self.__triggers[point_name]: if trigger_tuple[1] == callback: self.__triggers[point_name].remove(trigger_tuple) return raise TriggerException("Trying to remove an unexisting trigger") def point(self, point_name, *args, **kwargs): """This put a trigger point All the triggers for that point will be run @param point_name: name of the trigger point @param *args: args to transmit to trigger @param *kwargs: kwargs to transmit to trigger if "triggers_no_cancel" is present, it will be popup out when set to True, this argument don't let triggers stop the workflow @return: True if the action must be continued, False else """ if point_name not in self.__triggers: return True can_cancel = not kwargs.pop('triggers_no_cancel', False) for priority, trigger in self.__triggers[point_name]: try: if not trigger(*args, **kwargs) and can_cancel: return False except SkipOtherTriggers: break return True def returnPoint(self, point_name, *args, **kwargs): """Like point but trigger must return (continue, return_value) All triggers for that point must return a tuple with 2 values: - continue, same as for point, if False action must be finished - return_value: value to return ONLY IF CONTINUE IS FALSE @param point_name: name of the trigger point @return: True if the action must be continued, False else """ if point_name not in self.__triggers: return True for priority, trigger in self.__triggers[point_name]: try: cont, ret_value = trigger(*args, **kwargs) if not cont: return False, ret_value except SkipOtherTriggers: break return True, None