What are User Groups For?

User groups serve only two purposes in this program:

1. They are used in an event's Notification List as shorthand for a list of email addresses, and

2. They are used in an event's Access Level to control visibility of an event if set to private to group

User groups are maintained by the User Group Manager.

User Groups in Notification Lists

When used in an event's Notification List a user group is a shorthand for a longer list of other user ids or other user groups - allowing for hierarchical grouping. Whenever an event is modified an email is sent to everyone on the Notification List. The list of email addresses is expanded from the user groups down to the level of individual users. If any user in the group has an email address specified then an email is sent to that user.

The email field in a user group is yet another level of shorthand. If the email field contains a valid email address the user group is not expanded when looking for email addresses. Just the single user group email address is used. This allows you to minimize the number of emails that is being sent by this program (an important consideration for heavily trafficked calendars). The single email address can be expanded at the mail server which is probably a better place than at your web server (even though in some cases it may be the same machine).

User Groups in Access Levels

When the user group is used to contain the visibility of an event it works as follows. First you must set the Private to group setting in an event's Access Level field. Any users who share a common user group with the creator of that event will be able to see the event. Any user who does not share at least one user group with the creator of the event will not be able to see the event. For example, if a user belongs to two user groups (say group1 and group2) and adds an event with Access Level set to private to group then only users of either group1 or group2 (and users with higher permission such as ADMIN users) can see that event. To all other users the event does not exist.