CeleryRedisScheduler¶

class beatdrop.schedulers.celery_redis_scheduler.CeleryRedisScheduler¶

Bases: RedisScheduler, CeleryScheduler

Hold schedule entries in Redis, and send to Celery task queues.

Uses Redis to store schedule entries and scheduler state. It is safe to run multiple CeleryRedisScheduler s simultaneously, as well as have many that are used as clients to read/write entries.

Parameters:

max_interval (datetime.timedelta) – The maximum interval that the scheduler should sleep before waking up to check for due tasks.
sched_entry_types (Tuple[Type[ScheduleEntry]], default : (CrontabEntry, CrontabTZEntry, EventEntry, IntervalEntry)) – A list of valid schedule entry types for this scheduler. These are only stored in the scheduler, not externally.
default_sched_entries (List[ScheduleEntry], default : []) – Default list of schedule entries. In general these entries are not held in non-volatile storage so any metadata they hold will be lost if the scheduler fails. These entries are static. The keys cannot be overwritten or deleted.
lock_timeout (datetime.timedelta) – The time a scheduler does not refresh the scheduler lock before it is considered dead. Should be at least 3 times the max_interval.
redis_py_kwargs (Dict[str, Any]) – redis-py’s redis.Redis() key word arguments. Some of the client configuration items may be overwritten. https://redis-py.readthedocs.io/en/stable/connections.html#generic-client
celery_app (celery.Celery) – Celery app for sending tasks.

Example

from celery import Celery
from beatdrop import CeleryRedisScheduler

celery_app = Celery()
sched = CeleryRedisScheduler(
    max_interval=60,
    celery_app=celery_app,
    lock_timeout=180,
    redis_py_kwargs={
        "host": "my.redis.host",
        "port": 6379,
        "db": 0,
        "password": "mys3cr3t"
    }
)
# use the scheduler as a client
entry_list = sched.list()
for entry in entry_list:
    print(entry.key)

# or run it
sched.run()

delete(sched_entry: ScheduleEntry) → None¶

Delete a schedule entry from the scheduler.

This does not delete default entries.

Parameters:: sched_entry (ScheduleEntry) – Scheduler entry to delete from the scheduler.

get(key: str) → ScheduleEntry¶

Retrieve a schedule entry by its key.

Parameters:: key (str) – The schedule entry key.
Returns:: The schedule entry with the matching key.
Return type:: ScheduleEntry
Raises:: beatdrop.exceptions.ScheduleEntryNotFound – The schedule entry could not be found.

list(page_size: int = 500) → RedisScheduleEntryList¶

List schedule entries.

Parameters:: page_size (int, optional) – Redis suggested minimum page size, by default 500
Returns:: Iterator of all schedule entries. Automatically paginated redis results.
Return type:: RedisScheduleEntryList

run(max_iterations: int = None) → None¶

Run the scheduler.

Parameters:

max_iterations (int) –

default : None

The maximum number of iterations to run the scheduler. None is unlimited.

save(sched_entry: ScheduleEntry, read_only_attributes: bool = False) → None¶

Save a new, or update an existing schedule entry in redis.

Parameters:

sched_entry (ScheduleEntry) – Schedule entry to create or update.
read_only_attributes (bool, optional) – If true, read only attributes are also saved to the DB. Clients should almost always leave this false, by default False

send(sched_entry: ScheduleEntry) → None¶

Send a schedule entry to the Celery queue.

Parameters:: sched_entry (ScheduleEntry) – Schedule entry to send to the Celery queue.