Merge pull request #10 from Koed00/dev

Schedules of type ONCE will selfdestruct with negative repeats

django_q/cluster.py

@@ -442,14 +442,21 @@ def scheduler(list_key=Conf.Q_LIST):
                 next_run = next_run.replace(years=+1)
             s.next_run = next_run.datetime
             s.repeats += -1
-        else:
-            s.repeats = 0
         # send it to the cluster
         kwargs['list_key'] = list_key
         s.task = tasks.async(s.func, *args, **kwargs)
+        # log it
         if not s.task:
             logger.error(_('{} failed to create a task from schedule {} [{}]').format(current_process().name, s.id),
                          s.func)
         else:
             logger.info(_('{} created a task from schedule {} [{}]').format(current_process().name, s.id, s.func))
+        # default behavior is to delete a ONCE schedule
+        if s.schedule_type == s.ONCE:
+            if s.repeats < 0:
+                s.delete()
+                return
+            # but not if it has a positive repeats
+            s.repeats = 0
+        # save the schedule
         s.save()

django_q/tests/test_scheduler.py

@@ -1,6 +1,8 @@
 from multiprocessing import Queue, Event, Value
 
 import pytest
+import arrow
+from django.utils import timezone
 
 from django_q.conf import redis_client
 from django_q.cluster import pusher, worker, monitor, scheduler
@@ -45,10 +47,30 @@ def test_scheduler(r):
     assert schedule.repeats == 0
     assert schedule.last_run() is not None
     assert schedule.success() is True
+    assert schedule.next_run < arrow.get(timezone.now()).replace(hours=+1)
     task = fetch(schedule.task)
     assert task is not None
     assert task.success is True
     assert task.result < 0
+    # Once schedule with delete
+    once_schedule = create_schedule('django_q.tests.tasks.word_multiply',
+                                    2,
+                                    word='django',
+                                    schedule_type=Schedule.ONCE,
+                                    repeats=-1,
+                                    hook='django_q.tests.tasks.result'
+                                    )
+    assert hasattr(once_schedule, 'pk') is True
+    # negative repeats
+    always_schedule = create_schedule('django_q.tests.tasks.word_multiply',
+                                      2,
+                                      word='django',
+                                      schedule_type=Schedule.DAILY,
+                                      repeats=-1,
+                                      hook='django_q.tests.tasks.result'
+                                      )
+    assert hasattr(always_schedule, 'pk') is True
+    # All other types
     for t in Schedule.TYPE:
         schedule = create_schedule('django_q.tests.tasks.word_multiply',
                                    2,
@@ -59,4 +81,7 @@ def test_scheduler(r):
                                    )
         assert schedule is not None
         assert schedule.last_run() is None
-    scheduler()
+        scheduler(list_key=list_key)
+    scheduler(list_key=list_key)
+    # ONCE schedule should be deleted
+    assert Schedule.objects.filter(pk=once_schedule.pk).exists() is False

docs/admin.rst

@@ -41,12 +41,14 @@ In this case you would set the schedule type to :attr:`Schedule.HOURLY` and the
 
 When you set repeats to `-1` the schedule will continue indefinitely and the repeats will still count down. This can be used as an indicator of how many times the schedule has been executed.
 
-An exception to this are schedules of type :attr:`Schedule.ONCE`. Repeats are ignored by this schedule type and it will always reset it zero after execution.
+An exception to this are schedules of type :attr:`Schedule.ONCE`. Negative repeats for this schedule type will cause it to be deleted from the database.
+This behavior is useful if you have many delayed actions which you do not necessarily need a result for. A positive number will keep the ONCE schedule, but it will not run again.
 
 .. note::
 
     To run a `Once` schedule again, change the repeats to something other than `0`. Set a new run time before you do this or let it execute immediately.
 
+
 Next run
 ~~~~~~~~
 

docs/schedules.rst

@@ -116,7 +116,9 @@ Reference
 
     .. py:attribute:: ONCE
 
-    `'O'` the schedule will only run once. Repeats are ignored and set to `0` after execution.
+    `'O'` the schedule will only run once.
+    If it has a negative :attr:`repeats` it will be deleted after it has run.
+    If you want to keep the result, set :attr:`repeats` to a positive number.
 
     .. py:attribute:: HOURLY