django-eventtools is a lightweight library designed to handle repeating and one-off event occurrences for display on a website.
Download the source from https://pypi.python.org/pypi/django-eventtools/
python setup.py install, or:
> pip install django-eventtools
Django 1.8 or higher is required.
Given the following models:
from django.db import models from eventtools.models import BaseEvent, BaseOccurrence class MyEvent(BaseEvent): title = models.CharField(max_length=100) class MyOccurrence(BaseOccurrence): event = models.ForeignKey(MyEvent)
Create a sample event & occurrences
>>> from datetime import datetime >>> from myapp.models import MyEvent >>> event = MyEvent.objects.create(title='Test event') >>> once_off = MyOccurrence.objects.create( event=event, start=datetime(2016, 1, 1, 12, 0), end=datetime(2016, 1, 1, 2, 0)) >>> christmas = MyOccurrence.objects.create( event=event, start=datetime(2015, 12, 25, 7, 0), end=datetime(2015, 12, 25, 22, 0), repeat='RRULE:FREQ=YEARLY') >>> daily = MyOccurrence.objects.create( event=event, start=datetime(2016, 1, 1, 7, 0), end=datetime(2016, 1, 1, 8, 0), repeat='RRULE:FREQ=DAILY')
Event and Occurrence instances, and their associated querysets, all support
all_occurrences method, which takes two optional arguments -
to_date, which may be dates or datetimes.
None. The method returns a python generator
yielding tuples in the format
(start, end, instance) - for example:
>>> MyEvent.objects.all().all_occurrences() >>> event.all_occurrences(from_date=datetime(2015, 1, 1, 10, 0)) >>> event.occurrence_set.all().all_occurrences(to_date=date(2016, 1, 1)) >>> occurrence.all_occurrences(from_date=date(2016, 1, 1), to_date=date(2016, 12, 31))
instance is an instance of the corresponding BaseOccurrence subclass.
next_occurrence method is also provided, taking the same arguments,
but returning a single occurrence tuple.
>>> event.next_occurrence() >>> event.next_occurrence(from_date=date(2016, 1, 1))
first_occurrence also returns a single occurrence tuple, but
takes no arguments.
Event and Occurrence querysets can be filtered, but due to uncertainty
from_date filtering is only an approximation (whereas
to_date filtering is accurate). If you need a queryset filtered exactly,
exact=True - this will filter using generated occurrences but still
return a queryset - but be careful with this as it may be very slow and/or
CPU-hungry. For example
>>> MyEvent.objects.for_period(from_date=date(2015, 1, 1), to_date=date(2015, 12, 31)) >>> event.occurrence_set.for_period(from_date=date(2015, 1, 1), exact=True)
Event and Occurrence querysets can also be sorted by their next occurrence
sort_by_next method. By default this sorts instances by their
first occurrence; the optional
from_date argument will sort by the next
from_date. For example
>>> MyEvent.objects.all().sort_by_next() >>> event.occurrence_set.for_period(from_date=date(2015, 1, 1)) \ >>> .sort_by_next(date(2015, 1, 1))
Note that this method returns a sorted list, not a queryset.
Custom repeat intervals
Occurrences can repeat using any interval that can be expressed as an
To customise the available options, set
your django settings. The default value is
EVENTTOOLS_REPEAT_CHOICES = ( ("RRULE:FREQ=DAILY", 'Daily'), ("RRULE:FREQ=WEEKLY", 'Weekly'), ("RRULE:FREQ=MONTHLY", 'Monthly'), ("RRULE:FREQ=YEARLY", 'Yearly'), )
EVENTTOOLS_REPEAT_CHOICES = None to make repeat a plain-text field.
Occurrence cancellations or modifications
Cancelling or modifying a single occurrence repetition is not currently supported, but can be implemented by overriding a couple of methods. For example, the following allows cancellations or one-off modifications to the start time of a repetition:
from eventtools.models import (BaseEvent, BaseOccurrence, default_naive) from django.db import models class MyEvent(BaseEvent): pass class MyEventOccurrence(BaseOccurrence): event = models.ForeignKey(MyEvent) overrides = models.ManyToManyField('MyEventOccurrenceOverride', blank=True) def get_repeater(self): rule = super().get_repeater() # gets rruleset from parent method ruleset.rrule(rule) for override in self.overrides.all(): ruleset.exdate(default_naive(override.start)) # remove occurrence if override.modified_start: # reschedule occurrence if defined ruleset.rdate(default_naive(override.modified_start)) return ruleset class MyEventOccurrenceOverride(models.Model): start = models.DateTimeField() # must match targeted repetition exactly # new start, leave blank to cancel modified_start = models.DateTimeField(blank=True, null=True)
Note that start times must match exactly, so if the MyEventOccurrence start is changed, any previously-matching overrides will no longer be applied.
Use tox (https://pypi.python.org/pypi/tox):
> pip install tox > cd path-to/django-eventtools > tox