Re: "Run" pulldown menu in TreeView, TaskDuration, LandingTimes

[siddharth anand <sa...@apache.org>]

That sounds correct to me. Is there a PR?
-s

On Sat, Jul 16, 2016 at 12:40 AM, wood stock <ws...@gmail.com> wrote:

> Hi,
> I found an issue with the "Number of runs:" pulldown menu. Looks like we
> intend to retrieve task instances for the last X runs until the "Base".
> However, the logic has a flaw IMO.
>
> It is currently implemented as below (see copy snippet at the end). It
> tries to calculate execution_date of the last 'num_runs' based on DAG's
> interval. This will work if the schedule interval does not change, or if
> there are not manual/external triggered runs. An extreme example is a DAG
> with no schedules and purely depend on CLI to start the run. This will also
> not work if a DAG is triggered by another DAG because there is no fixed
> schedule interval between runs.
>
> IMO, the correct way is to query the database for TIs which have
> execution_date earlier than "base" with maximum number of query entries be
> 'num_runs', or just implement
>
> dates = dag.date_range(base_date, num=-abs(num_runs))
> min_date = dates[0] if dates else datetime(2000, 1, 1)
> for ti in task.get_task_instances(session, start_date=min_date,
>  end_date=base_date)
>
> Thanks!
>
>
>     def date_range(self, start_date, num=None, end_date=datetime.now()):
>         if num:
>             end_date = None
>         return utils_date_range(
>             start_date=start_date, end_date=end_date,
>             num=num, delta=self._schedule_interval)
>