Adding wp_unschedule_hook function

[arena]

Unschedule all previously scheduled cron job for a hook.

Can be usefull for plugins when deactivating to clean up the cron queue

The $hook parameter is required, so that the events can be identified.

@param string $hook Action hook, the execution of which will be unscheduled.

[SergeyBiryukov]

Isn't that what wp_clear_scheduled_hook() already does?

[dd32]

Isn't that what wp_clear_scheduled_hook() already does?

That clears by hook + args, It's common place to hook multiple "instances" of a job with varying parameters (ie. Post ID to process) to a single hook, there's no API to clear all events for that hook at present. I've seen this requested before, it might be on trac, or elsewhere, I'm not sure.

[SergeyBiryukov]

That makes sense, I had a feeling I must have missed something.

[arena]

dd32 is right :

"there's no API to clear all events for a hook at present"

i coded it myself for a plugin but think it ought to be in the API

[arena]

just giving a bump to this ticket to have it included in 3.4

thank you

[Viper007Bond]

Patch seems to be okay although it will need to be cleaned up to meet ​WordPress coding standards.

[arena]

Done !

[Viper007Bond]

Replying to arena:

Done !

Just one more minor nitpick:

if ( empty( $crons[$timestamp] ) )
	unset( $crons[$timestamp] );

We do if's like that (line break in there) and with some extra spaces inside of the empty(). :)

[arena]

Done !

[nacin]

Perhaps too clever, or slower, but instead of if ( empty ) unset();, we could also hold off until before we call _set_cron_array() and then do $cron = array_filter( $cron ); That will clear out empty values.

[arena]

Nacin, your point is interesting.

May be this should be done once for all in

_set_cron_array()

simplifying all other functions calling _set_cron_array()

[arena]

Replying to arena:

Nacin, your point is interesting.

May be this should be done once for all in

_set_cron_array()

simplifying all other functions calling _set_cron_array()

since nacin tip, i reviewed the cron api and made some code changes :

• to have _get_cron_array closer to _set_cron_array when possible
• generalization of test empty( $crons ) after _get_cron_array()
• added a '$action' argument in function _set_cron_array()

patch is named #cron

[nacin]

A good idea, but too late for 3.4.

[arena]

not fair, nacin opened 5 months ago ...

[nacin]

Replying to arena:

not fair, nacin opened 5 months ago ...

Cron had a few changes already in 3.4, specifically microtime locking. This however digs a bit deeper into the API and deserves a more thorough review. If we end up setting or getting the cron array out of order, we risk a bug or race condition. I think the patch will be great for 3.5.

[nacin]

I am fine with reviving #18997.patch​ for 3.4, but we will first need unit tests: ​http://unit-tests.trac.wordpress.org/browser/wp-testcase/test_cron.php.

[Viper007Bond]

Please don't close valid tickets. Even if you no longer desire the feature, I'm sure others do. Thanks. :)

[mordauk]

18997.patch is a refreshed patch that improves some formatting, adds brackets, and uses the src directory structure.

[mordauk]

18997-tests.patch introduces the test_unschedule_hook() test.

[jpswade]

Had a problem today where I accidentally scheduled the function that adds the schedule.

Although I spotted and fixed the error, it was impossible to remove the hook without this function.

​http://wordpress.stackexchange.com/questions/39681/delete-all-scheduled-events-with-a-particular-hook

This case here outlines the same issue.

[jrf]

What can be done to move this ticket forward ? I'm all for this.

I've tested @mordauk's patch & unit tests and both seem to work as expected.

Uploading refreshed patch - which includes both his original patch + the unit test - now just in case that's the issue. Props should go to @mordauk.

[chriscct7]

@jrf not much needs to be done. I'm going to give it a quick run through, and then it will be milestoned for 4.5

[jipmoors]

@chriscct7 are you able to give this a look? Otherwise I would suggest asking @SergeyBiryukov to take that look for you :)

[jrf]

Can this please be earmarked for 4.9 ?

[jrf]

@chriscct7 Thanks for that. Is the patch still good or would you like me to refresh it ?

[swissspidy]

+1 from me as a component maintainer.

[SergeyBiryukov]

In 40965:

Cron API: Introduce wp_unschedule_hook() to clear all events attached to a hook.

This complements wp_clear_scheduled_hook(), which only clears events attached with specific arguments.

Props arena, mordauk, jrf.
Fixes #18997.