Testing and QA

This feature branch has been developped for a while and I think it is time for some community feedback.

This branch is developped due to the fact that current enrolment plugin system can not allow multiple plugin work at the sametime.

Because of the nature of this branch the enrolment plugin architecture has been changed. All enrolment plugins shipped with moodle official release are modified to meet the new architecture.

I will discuss them here from a user's and a developer's point of view.

If you are an end user:

1. Enrolment admin panel is now enhanced. It now allows you to select multiple plugins you wish to use.
1.1 Internal plugin is always enabled as it is required to do some internal work.
1.2 Enrolment plugins those requires interactive actions with users can be selected as the default interactive plugin for the site.
1.3 Click the "Edit" link on the right side of the plugins to configure them using the origial configuration interface. Don't forget to configure plugins you enabled correctly!
2. There are a few extra options in the course settings.
2.1 You can choose different interactive enrolment plugin from the site default for single courses.
2.2 If you do not want any interactive plugins to be enabled in a course just set "Enrollable" setting in the course to "No". Non-interactive ones will still work.


If you are a developer:

As mentioned above this branch changed the enrolment plugin API. So some detailed explaination is avaiable as below:

1. Changes to the enrolment plugin class structure:
1.1 There are no base class any more. All enrolment plugins are independent classes.
1.2 The origial base class is now the internal plugin class.
1.3 A new enrolment_factory class is introduced to produce enrolment plugins required. Should an instance of any plugin is required, use

$plugin = enrolment_factory::factory('plugin_name');

If plugin_name is not specified the default plugin for the site will be created.
1.4 If any enrolment plugin does not implement print_entry() method it will be considered as a non-interactive plugin. In the new plugin configuration panel only interactive plugins will be able to set as default plugin. As non-interactive plugins will load student/teacher information everytime user is logged in and when user is attempting to enrol to a course, it is meanless to set them as the "gate" of a course.
1.5 If any method in the internal class is required just factory an instance of internal plugin and call the required method.
2. Setting "Enrollable" to "No" in a course will disable users to enrol interactively. So it is fine to leave internal plugin always enabled and as the default way of enrolling.
3. Enabled plugins are stored as a comma-seperated list in config varaible enrol_plugins_enabled. It is ensured that internal plugin is always at the top of the list so it will produce a complete user-course array for the rest of the plugins to use.
4. The old $CFG->enrol is used to store the default site interactive plugin. It may be empty as there is a block of code that if $CFG->enrol is empty, populate it with 'internal', which is exactly what we want.
5. A new field called "enrol" is added to course table storing the plugin that the course uses. If it is empty, site default will be used.
6. The upgrade script will try to figure out whether your current enrolment plugin is interactive or not. If not, "Enrollable" option for all courses will be set to "No".
7. The interal get_student_courses() method will populate the user-course array in a slightly different way. A boolean value of true indicating the user is enrolled to a course is now replaced by a string of the name of the enrolment plugin that enrolled this user to the course. In this way there are no need to query database to ask if the user is enrolled by a particular plugin when trying to unenrol a user. Also this may be used to prevent a plugin to mess up with users enrolled by another plugin.


There might be something that I didn't cover, if you have any questions/comments/suggestions/whatever please feel free to reply.

Just in case you don't know how, to get a copy of this feature branch use the following cvs command:

cvs -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/moodle checkout -r MOODLE_16_MULTIENROL moodle