flumotion.component.base.scheduler

35 """ 36 I keep track of upcoming events. 37 38 I can provide notifications when events end and start, and maintain 39 a set of current events. 40 """ 41 windowSize = timedelta(days=1) 42

43 - def __init__(self):

44 self._delayedCall = None 45 self._subscribeId = 0 46 self.subscribers = {} 47 self._eventSets = {} 48 self._nextStart = 0

49

50 - def _addEvent(self, event):

51 self.debug("adding event %s", event.uid) 52 uid = event.uid 53 if uid not in self._eventSets: 54 self._eventSets[uid] = EventSet(uid) 55 self._eventSets[uid].addEvent(event) 56 if event.start < event.now < event.end: 57 self._eventStarted(event)

58

59 - def addEvent(self, uid, start, end, content, rrule=None, now=None, 60 exdates=None):

61 """Add a new event to the scheduler 62 63 @param uid: uid of event 64 @type uid: str 65 @param start: wall-clock time of event start 66 @type start: datetime 67 @param end: wall-clock time of event end 68 @type end: datetime 69 @param content: content of this event 70 @type content: str 71 @param rrule: recurrence rule, either as a string parseable by 72 datetime.rrule.rrulestr or as a datetime.timedelta 73 @type rrule: None, str, or datetime.timedelta 74 75 @returns: an Event that can later be passed to removeEvent, if 76 so desired. The event will be removed or rescheduled 77 automatically when it ends. 78 """ 79 80 if now is None: 81 now = datetime.now(LOCAL) 82 event = Event(uid, start, end, content, rrule=rrule, exdates=exdates, 83 now=now) 84 if event.end < now and not rrule: 85 self.warning('attempted to schedule event in the past: %r', 86 event) 87 return event 88 89 self._addEvent(event) 90 self._reschedule() 91 return event

92

93 - def removeEvent(self, event):

94 """Remove an event from the scheduler. 95 96 @param event: an event, as returned from addEvent() 97 @type event: Event 98 """ 99 self._removeEvent(event) 100 self._reschedule()

101

102 - def _removeEvent(self, event):

103 uid = event.uid 104 if uid not in self._eventSets: 105 return 106 current = self.getCurrentEvents() 107 if event in current: 108 self._eventEnded(event) 109 self._eventSets[uid].removeEvent(event)

110

111 - def getCurrentEvents(self, now=None, windowSize=None):

112 """Get a list of current events. 113 @param now: Use now as localtime. If not set the local time is used. 114 @type now: datetime 115 @param windowSize: get events on this window. If not set, the returned 116 events will be on the class windowSize member. 117 @type windowSize: timedelta 118 119 @return: Events that are being run. 120 @rtype: L{Event} 121 """ 122 if now is None: 123 now = datetime.now(LOCAL) 124 if windowSize is None: 125 windowSize = timedelta(seconds=0) 126 current = [] 127 for eventSet in self._eventSets.values(): 128 points = eventSet.getPoints(now, now + windowSize) 129 for point in points: 130 event = point.eventInstance.event 131 event.currentStart = point.eventInstance.currentStart 132 event.currentEnd = point.eventInstance.currentEnd 133 if not event in current: 134 current.append(event) 135 return current

136

137 - def addEvents(self, events):

138 """ 139 Add a new list of events to the schedule. 140 141 @param events: the new events 142 @type events: list of Event 143 """ 144 result = [] 145 for event in events: 146 e = self._addEvent(event) 147 result.append(e) 148 self._reschedule() 149 return result

150

151 - def replaceEvents(self, events, now=None):

152 """Replace the set of events in the scheduler. 153 154 This function is different than simply removing all events then 155 adding new ones, because it tries to avoid spurious 156 ended/started notifications. 157 158 @param events: the new events 159 @type events: a sequence of Event 160 """ 161 if now is None: 162 now = datetime.now(LOCAL) 163 currentEvents = self.getCurrentEvents() 164 for _, eventSet in self._eventSets.iteritems(): 165 eventsToRemove = eventSet.getEvents()[:] 166 for event in eventsToRemove: 167 if event not in currentEvents: 168 self._removeEvent(event) 169 for event in events: 170 self.debug("adding event %r", event.uid) 171 if event.start > now or event.rrule: 172 self._addEvent(event) 173 else: 174 self.debug("event is a past event and it is not added") 175 self._reschedule()

176 193

194 - def unsubscribe(self, id):

195 """Unsubscribe from event happenings in the scheduler. 196 197 @param id: Subscription ID received from subscribe() 198 """ 199 del self.subscribers[id]

200

201 - def _eventStarted(self, event):

202 for started, _ in self.subscribers.values(): 203 started(event)

204

205 - def _eventEnded(self, event):

206 for _, ended in self.subscribers.values(): 207 ended(event)

208

209 - def _reschedule(self):

210 211 def _getNextEvent(now): 212 earliest = now + self.windowSize 213 which = None 214 result = None 215 for event in self.getCurrentEvents(now, self.windowSize): 216 self.debug("current event %s", event.uid) 217 if event.currentStart < earliest and event.currentStart > now: 218 earliest = event.currentStart 219 which = 'start' 220 result = event 221 if event.currentEnd < earliest: 222 earliest = event.currentEnd 223 which = 'end' 224 result = event 225 return result, which

226 227 def doStart(e): 228 self._eventStarted(e) 229 self._reschedule()

Source Code for Module flumotion.component.base.scheduler