schedules
prefect.server.schemas.schedules
Schedule schemas
Classes
IntervalSchedule
A schedule formed by adding interval increments to an anchor_date. If no
anchor_date is supplied, the current UTC time is used. If a
timezone-naive datetime is provided for anchor_date, it is assumed to be
in the schedule’s timezone (or UTC). Even if supplied with an IANA timezone,
anchor dates are always stored as UTC offsets, so a timezone can be
provided to determine localization behaviors like DST boundary handling. If
none is provided it will be inferred from the anchor date.
NOTE: If the IntervalSchedule anchor_date or timezone is provided in a
DST-observing timezone, then the schedule will adjust itself appropriately.
Intervals greater than 24 hours will follow DST conventions, while intervals
of less than 24 hours will follow UTC intervals. For example, an hourly
schedule will fire every UTC hour, even across DST boundaries. When clocks
are set back, this will result in two runs that appear to both be
scheduled for 1am local time, even though they are an hour apart in UTC
time. For longer intervals, like a daily schedule, the interval schedule
will adjust for DST boundaries so that the clock-hour remains constant. This
means that a daily schedule that always fires at 9am will observe DST and
continue to fire at 9am in the local time zone.
Args:
interval: an interval to schedule on.anchor_date: an anchor date to schedule increments against; if not provided, the current timestamp will be used.timezone: a valid timezone string.
Methods:
validate_timezone
CronSchedule
Cron schedule
NOTE: If the timezone is a DST-observing one, then the schedule will adjust itself appropriately. Cron’s rules for DST are based on schedule times, not intervals. This means that an hourly cron schedule will fire on every new schedule hour, not every elapsed hour; for example, when clocks are set back this will result in a two-hour pause as the schedule will fire the first time 1am is reached and the first time 2am is reached, 120 minutes later. Longer schedules, such as one that fires at 9am every morning, will automatically adjust for DST.
Args:
cron: a valid cron stringtimezone: a valid timezone string in IANA tzdata format (for example, America/New_York).day_or: Control how croniter handlesdayandday_of_weekentries. Defaults to True, matching cron which connects those values using OR. If the switch is set to False, the values are connected using AND. This behaves like fcron and enables you to e.g. define a job that executes each 2nd friday of a month by setting the days of month and the weekday.
Methods:
validate_timezone
valid_cron_string
RRuleSchedule
RRule schedule, based on the iCalendar standard
(RFC 5545) as
implemented in dateutils.rrule.
RRules are appropriate for any kind of calendar-date manipulation, including irregular intervals, repetition, exclusions, week day or day-of-month adjustments, and more.
Note that as a calendar-oriented standard, RRuleSchedules are sensitive to
to the initial timezone provided. A 9am daily schedule with a daylight saving
time-aware start date will maintain a local 9am time through DST boundaries;
a 9am daily schedule with a UTC start date will maintain a 9am UTC time.
Args:
rrule: a valid RRule stringtimezone: a valid timezone string
Methods:
validate_rrule_str
from_rrule
to_rrule
Since rrule doesn’t properly serialize/deserialize timezones, we localize dates here