Many digest users have been having issues running digests, particularly versions 3.2.2 and 3.2.3. At the suggestion of a user I introduced a feature that allows month abbreviations and days of week to be language independent by using phpBB’s $user->format_date() function. Aside from most if not all of digests not going out for a particular hour, while you will see a “Starting digests mailer” entry in the admin log you won’t see an “Ending digests mailer”. In the phpBB error log you should see this:
Error while creating image
» Error in [ROOT]/phpbb/user.php on line 599: DateTime::setTimezone() expects parameter 1 to be DateTimeZone, null given
What is going on is that phpBB expects a PHP DateTimeZone object to be created and attached to the important $user object as $user->timezone. If it’s not there, the error will be triggered because the object doesn’t exist:
In my testing, this happens when “Anonymous” (the guest account, or user_id = 1) is running digests. Essentially “Anonymous” is hitting the forum and triggering phpBB’s cron. phpBB’s cron may trigger the digest cron (if an hour has elapsed since digests were last run). Even though “Anonymous” has a timezone associated with the account (GMT) either the timezone object is not getting created or it is getting destroyed when it goes through the loop that sends out all digests for a given hour.
The solution is documented here and should be applied to versions 3.2.3 and 3.2.2 if that is installed. The instructions assume 3.2.3 is installed. Essentially before calling $user->format_date() it tests to see if the timezone object exists and if it doesn’t it creates it. There are three possible instances that could trigger this, so all should be fixed.
There is a general problem with the digests architecture. It extensively uses phpBB’s built in tools, such as this library, but also the templating system to create pretty digests, which assumes a live user is interacting with the forum. However, digests are often run by “Anonymous”, which is not quite a “full” user, or by a system cron. phpBB was clearly not designed to use these features (at least not very well) in “cron” mode. So as these problems are discovered, they must be found and fixed. And unfortunately these sorts of problems are devilishly hard to track down as they can’t be discovered interactively and only through tedious debugging of a sufficiently large forum by adding entries to the log. One of my clients essentially used his large forum to help me troubleshoot the issue and fix it.
The problem is not manifest when manually running the mailer. I can’t actually test digests from the command line (I need an email server in my development environment to do that) so I have to test in phpBB cron mode. A sufficiently large test database might have revealed this problem, but of course digests are highly dynamic so it’s hard to set up one of these.
Changes will get published to GitHub and this will probably be part of a new version, but not right away. I started reviewing the code to clean it up, and need to integrate these changes into that (and test it!) before releasing the next version.