2 Using the until argument

2 Using the `until` argument

If you specify until, the value can be one of many things, all intended to indicate a point in time until which to cache. The until argument accepts any one of the following:

A string of the form "hh:mi" or "hh:mi:ss", specifying a time in hours, minutes, and optionally seconds, on a 24-hour clock. This tells SkunkWeb to cache until the next occurrence of that time. If you say until=06:00, and SkunkWeb executes the component at 05:30, it will cache for 30 minutes; but if SkunkWeb executes the component at 07:00, it will cache for 23 hours until the next day at 06:00.
A string of the form ":mi", meaning ``minutes after the hour''. This tells SkunkWeb to cache until that many minutes after the current hour, or after the next hour if those minutes have already passed.
A DateTime object, as produced by functions in the Date or DateTime modules, or retrieved from a database using skunk.org's SQL module or SQL personality of SkunkWeb.
A string of the form "yyyy-mm-dd", "yyyy-mm-dd hh:mi", or "yyyy-mm-dd hh:mi:ss". These strings specify dates according to the ISO format supported by the Date module.
A string of the form "mm/dd/yyyy", "mm/dd/yyyy hh:mi", or "mm/dd/yyyy hh:mi:ss". These strings specify dates according to a common U.S. date format. These string forms are only supported for backward compatibility; if you must use a string specifying an explicit date, use the ISO format above.
A RelativeDateTime object from the DateTime module. these objects allow you to specify very complex relative dates, such as ``the first Sunday of next month at noon''. Be careful with these objects: unless you read the documentation fully, you can end up constructing a RelativeDateTime that moves you backwards in time. If you do that, the <:cache:> will raise an exception telling you of your mistake.

A tuple or list containing ANY combination of the above items. In this case, SkunkWeb will evaluate all items, and choose the result that is nearest the current date/time for the cache expiration. This means you can do neat complex cache control:

# expires the cache at 0, 15, 30, and 45 minutes after the hour
<:cache until=`(":00", ":15", ":30", ":45")`:>

# expires the cache at 15 minutes after the hour,
# and also at 06:00 every day, and also
# at 5pm (17:00) on Sundays.
<:import DateTime "RelativeDateTime":>
<:cache until=`(":15", "06:00", 
   RelativeDateTime(
        weekday=0, hour=17, 
        minute=0, second=0))`:>

The Python equivalent of the <:cache until=foo:> tag is:

import TimeUtil
__expiration = TimeUtil.convertUntil(foo)