fix long period task will never be triggered

[daydaychen]

Here, the entry reload time is taken as the default value when last_run_at is None,
and this value will be updated every time the schedule is updated/added.

For a periodic task with a long period, such as three days, if there is always an update/add within three days, the periodic task will never be triggered.

[daydaychen]

The side effect is that adding a periodic task will trigger once first.

[auvipy]

The side effect is that adding a periodic task will trigger once first.

can you elaborate more on this please?

[auvipy]

we need proper unit test for the change to make sure there won't be any regression

[daydaychen]

The side effect is that adding a periodic task will trigger once first.

can you elaborate more on this please?

When the last_run_at value is None, it defaults to the reload time of the entry.

For example, the first trigger time of a three-day interval scheduled task should be last_run_at +3 days, but each time the schedule_changed method return True, the entry will be re-instantiated and the last_run_at will be updated.

This can be a problem for the schedule_changed method frequently triggered by the management panel, because the last_run_at method will be frequently refreshed and may never be executed as planned.

Sorry, there were some side effects for the previous implementation.

I made some changes to the initial value of last_run_at.

Now, if it's None, it will be fetched from date_changed.

In this way, the default value of last_run_at will not affected by the schedule_changed, the above problems can be solved.

[daydaychen]

we need proper unit test for the change to make sure there won't be any regression

Ok, I'll make up the unit test later.

[auvipy]

waiting for unit tests to make sure this will not create any regression

[auvipy]

we need unit tests to make sure this won't create any regression/ unintended side effect