The topic of implementing a scheduled activity with Joomla is achieved usually by the use of a daemon named 'cron'. This is primarily due to most(?) Joomla systems running upon a UNIX based operating system. This is not always the situation and there are a number of Windows based systems available, but there is adequate documentation about Windows systems created by Microsoft and it is not necessary to repeat that information. With UNIX systems being so common we have included this section because an understanding of 'cron' is important in its implementation and also in the design of specific activities that leverage its facilities. Some of this information is also included in the Users Guide but is also included here for completeness.
Cron is basically a time-based job scheduler that runs in the background on UNIX systems. Typically a task requiring repetitive actions to be carried out on a regular (pre-determined) basis would be ideal candidates for using cron.
Issue Tracker release 1.5 introduced a number of tasks that could be automated. The number is likely to increase over time, but initially includes the generation and sending of reports of a) Summary of issue numbers over a specified time period, and b) overdue issues by assignee, which is sent to each assignee. Release 1.5 also enables the automatic raising of issues and optionally updates via email. See below for details of the criteria used for this implementation.
Joomla systems can offer a number of different mechanisms to perform repetitive actions, of which the one to be used is very dependant upon the facilities offered by the hosting supplier.
It is possible to make use of a ‘bespoke’ plugin which can be invoked when someone accesses one or more pages upon a site and performs some predefined tasks. This is really a 'real' cron since there is no real way in which one can guarantee that there would be a site visitor at any predetermine time, and has an unavoidable side effect of slowing the site access for the specific visitor that happen to visit the site at or immediately after the desired time. For this reason we have not implemented such a mechanism, however for some other ‘short’ running tasks it might be suitable, so although not suitable for our implementation can in some circumstances provide a reasonable solution.