Investigate MyRadio_Season::$timeslots caching when a timeslot is cancelled

[markspolakovs]

This is purely hypothetical, but is the only explanation I can come up with for the phenomenon in this slack thread.

When a timeslot is cancelled, we delete the row and update the local cache:

MyRadio/src/Classes/ServiceAPI/MyRadio_Timeslot.php

Lines 1029 to 1038 in 7cbb233

	private function deleteTimeslot()
	{
	$r = self::$db->query(
	'DELETE FROM schedule.show_season_timeslot WHERE show_season_timeslot_id=$1',
	[$this->getID()]
	);
	$this->updateCacheObject();
	return $r;
	}

However, MyRadio_Season has a local $timeslots field, which is populated at construction-time:

MyRadio/src/Classes/ServiceAPI/MyRadio_Season.php

Line 28 in 7cbb233

private $timeslots;

MyRadio/src/Classes/ServiceAPI/MyRadio_Season.php

Line 146 in 7cbb233

$this->timeslots = json_decode($result['timeslots']);

As far as I can tell, the cache for the season object doesn't get wiped when a timeslot gets deleted, which I suspect could trigger an exception like this:

Message: The MyRadio_Timeslot with instance ID #151553 does not exist.
Location:/usr/local/www/myradio/src/Classes/ServiceAPI/MyRadio_Timeslot.php:112
Trace:
#0 /usr/local/www/myradio/src/Classes/ServiceAPI/ServiceAPI.php(94): MyRadio\ServiceAPI\MyRadio_Timeslot->__construct('151553')
#1 /usr/local/www/myradio/src/Classes/ServiceAPI/ServiceAPI.php(85): MyRadio\ServiceAPI\ServiceAPI::factory('151553')
#2 /usr/local/www/myradio/src/Classes/ServiceAPI/ServiceAPI.php(141): MyRadio\ServiceAPI\ServiceAPI::getInstance('151553')
#3 /usr/local/www/myradio/src/Classes/ServiceAPI/MyRadio_Season.php(1218): MyRadio\ServiceAPI\ServiceAPI::resultSetToObjArray(Array)
#4 /usr/local/www/myradio/src/Controllers/MyRadio/timeslot.php(91): MyRadio\ServiceAPI\MyRadio_Season->getAllTimeslots()
#5 /usr/local/www/myradio/src/Controllers/root_web.php(105): require('/usr/local/www/...')
#6 /usr/local/www/myradio/src/Public/index.php(17): require('/usr/local/www/...')
#7 {main}

MyRadio/src/Controllers/MyRadio/timeslot.php

Lines 84 to 93 in 7cbb233

	foreach ($shows as $show) {
	foreach ($show->getAllSeasons() as $season) {
	$data[$show->getMeta('title')][] = array_map(
	function ($x) {
	return [$x->getID(), $x->getStartTime(), $x->getEndTime()];
	},
	$season->getAllTimeslots()
	);
	}
	}