Last Modified 2011-01-30 by Ben Klang

Horde Group API

This document is intended to clarify the Horde Group API, and to provide a solid target for applications to move toward for Horde4. Motivation for this document was spurred from the conversation between the Bens on IRC regarding the "proper" way to handle groups with LDAP.


In its simplest terms a group consists of an ID and a Name. The ID is unique to that group and is unchanging. The name is a human-friendly name that can be changed as desired. The source and/or format of the group ID should not be of concern to the application using it, and should always be obtained/modified/stored through the group API calls. The group ID is the only acceptable method as to refer to a group, as it is guaranteed to be unique (uniqueness being the job of the driver). The group name is strictly for interface use.

Functional Changes

Horde 4 will deviate from Horde 3 in these key ways:

  • The groups collection will be flat. Groups cannot be created as children of existing groups.
    • Groups can belong to other groups. In this way complex collections of users can be expressed without duplication.


  • Make sure we handle group structures that represent an infinite loop
    • Create a UI that allows administrators to be able to view all effective users in a group (including those that are a part of the group through group membership).
    • How do we handle backends that can't support nested group membership? Example: LDAP can store this information but cannot integrate with other systems like Unix, which has not concept of nested groups.


This is the class that does the work of reading from/saving to the group storage backend.
This class should not be used directly, instead Horde_Group objects are created and used.


Creates a new group and returns a new Horde_Group object.

  • Add handlers for $name and $parent parameters from newGroup()

renameGroup($gid, $newName)

Changes the name of a group without affecting its membership list


Removes a group from the groups system permanently.


Returns a Horde_Group object based on $name

If the name does not match exactly 1 group (too few or too many) it will raise Horde_Group_Exception with an appropriate error message


Returns Horde_Group object based on the $gid.


Boolean: Check if a group exists in the system.


Returns an array of all groups, in the format gid => name.

listUsers($gid, $recurse = false)

Get a list of every user that is a part of this group ONLY.

If $recurse is true then also check member groups' user lists.


Returns an array of Horde_Group objects representing the user's membership

addUser($gid, $username)

Add a user to a group.

  • Should be able to handle arrays for both parameters.

removeUser($gid, $username)

Remove a user from a group.

  • Should be able to handle arrays for both parameters.


This object represents a group

new($name, $create = true)

Returns an instance of a Horde group. If $create is true and the group does not exist, it is created. If $create is false and the group does not exist, or if $create is true and the group already exists, a Horde_Group_Exception is raised.


Returns the group's ID


Returns the group's name


Adds $username to the group


Removes $username from the group

listUsers($recurse = true)


Boolean; does this group have $username as a member?


Deletes the group from the backend


Renames the group