4.8. Expansion of UMC modules with extended attributes#

The domain management UMC modules allow the comprehensive management of the data in a domain. Extended attributes offer the possibility of integrating new attributes in the domain management which are not covered by the UCS standard scope. Extended attributes are also employed by third party vendors for the integration of solutions in UCS.

Extended attributes are managed in the UMC module LDAP directory. There one needs to switch to the univention container and then to the custom attributes subcontainer. Existing attributes can be edited here or a new Settings: extended attribute object created here with Add.

Extended attribute for managing a car license

Extended attributes can be internationalized. In this case, the name and description should be compiled in English as this is the standard language for UMC modules.

4.8.1. Extended attributes - General tab#

Table 4.1 General tab#



Unique name

The name of the LDAP object which will be used to store the extended attribute. Within a container, the name has to be unique.

UDM CLI name

The specified attribute name should be used when employing the command line interface Univention Directory Manager. When the extended attribute is saved, the Unique name of the General tab is automatically adopted and can be subsequently modified.

Short description

Used as title of the input field in UMC modules or as the attribute description in the command line interface.

Translations of short description

Translated short descriptions can be saved in several languages so that the title of extended attributes is also output with other language settings in the respective national language. This can be done by assigning the respective short description to a language code (e.g., de_DE or fr_FR) in this input field.

Long description

This long description is shown as a tool tip in the input fields in UMC modules.

Translations of long description

Additional information displayed in the tool tip for an extended attribute can also be saved for several languages. This can be done by assigning the respective long description to a language code (e.g., de_DE or fr_FR) in this input field.

4.8.2. Extended attributes - Module tab#

Table 4.2 Module tab#



Modules to be extended

The Univention Directory Manager module which is to be expanded with the extended attribute. An extended attribute can apply for multiple modules.

Required options/object classes

Some extended attributes can only be used practically if certain object classes are activated on the Options tab. One or more options can optionally be saved in this input field so that this extended attribute is displayed or editable.

Hook class

The functions of the hook class specified here are used during saving, modifying and deleting the objects with extended attributes. Additional information can be found in Univention Developer Reference [3].

4.8.3. Extended attributes - LDAP mapping tab#

Table 4.3 LDAP mapping tab#



LDAP object class

Object class to which the attribute entered under LDAP attribute belongs.

Predefined LDAP schema extensions for extended attributes are provided with the object class univentionFreeAttributes. Further information can be found in LDAP schema extensions.

Each LDAP object which should be extended with an attribute is automatically extended with the LDAP object class specified here if a value for the extended attribute has been entered by the user.

LDAP attribute

The name of the LDAP attribute where the values of the LDAP object are to be stored. The LDAP attribute must be included in the specified object class.

Remove object class if the attribute is removed

If the value of an extended attribute in a UMC module is deleted, the attribute is removed from the LDAP object. If no further attributes of the registered object class are used in this LDAP object, the LDAP object class will also be removed from the LDAP object if this option is activated.

4.8.4. Extended attributes - UMC tab#

Table 4.4 UMC tab#



Do not show this extended attribute in UMC modules

This option can be activated if an attribute should only be administrated internally instead of by the administrator, e.g., indirectly by scripts. The attribute can then only be set via the command line interface Univention Directory Manager and is not displayed in UMC modules.

Exclude from UMC module

If it should not be possible to search for an extended attribute in the search window of a wizard, this option can be activated to remove the extended attribute from the list of possible search criteria.

This is only needed in exceptional cases.

Ordering number

If several extended attributes are to be managed on one tab, the order of the individual attributes on the tab can be influenced here. They are added to the end of the tab or the group in question in ascending order of their numbers.

Assigning consecutive position numbers results in the attributes being ordered on the left and right alternately in two columns. Otherwise, the positioning starts in the left column. If additional attributes have the same position number, their order is random.

Overwrite existing widget

In some cases it is useful to overwrite predefined input fields with extended attributes. If the internal UDM name of an attribute is configured here, its input field is overwritten by this extended attribute. The UDM attribute name can be identified with the command univention-directory-manager (see Command line interface of domain management (Univention Directory Manager)). This option may cause problems if it is applied to a mandatory attribute.

Span both columns

As standard all input fields are grouped into two columns. This option can be used for overlong input fields, which need the full width of the tab.

Tab name

The name of the tab in UMC modules on which the extended attribute should be displayed. New tabs can also be added here.

If no tab name is entered, user-defined will be used.

Translations of tab name

Translated tab names can be assigned to the corresponding language code (e.g. de_DE or fr_FR) in this input field.

Overwrite existing tab

If this option is activated, the tab in question is overwritten before the extended attributes are positioned on it. This option can be used to hide existing input fields on a predefined tab. It must be noted that this option can cause problems with compulsory fields. If the tab to be overwritten uses translations, the overwriting tab must also include identical translations.

Tab with advanced settings

Settings possibilities which are rarely used can be placed in the extended settings tab

Group name

Groups allow the structuring of a tab. A group is separated by a gray horizontal bar and can be shown and hidden.

If no group name is specified for an extended attribute, the attribute is placed above the first group entry.

Translations of group name

To translate the name of the group, translated group names for the corresponding language code can be saved in this input field (e.g., de_DE or fr_FR).

Group ordering number

If multiple groups are managed in one tab, this position number can be used to specify the order of the groups. They are shown in the ascending order of their position numbers.

4.8.5. Extended attributes - Data type tab#

Table 4.5 Data type tab#



Syntax class

When values are entered in UMC modules, a syntax check is performed.

Apart from standard syntax definitions (string) and (integer), there are three possibilities for expressing a binary condition. The syntax TrueFalse is represented at LDAP level using the strings true and false, the syntax TrueFalseUpper corresponds to the OpenLDAP boolean values TRUE and FALSE and the syntax boolean does not save any value or the string 1.

The syntax string is the default. An overview of the additionally available syntax definitions and instructions on integrating your own syntax can be found in Univention Developer Reference [3].

Default value

If a preset value is defined here, new objects to be created will be initialized with this value. The value can still be edited manually during creation. Existing objects remain unchanged.

Multi value

This option establishes whether a single value or multiple values can be entered in the input mask. The scheme definition of the LDAP attribute specifies whether one or several instances of the attribute may be used in one LDAP object.

Value required

If this option is active, a valid value must be entered for the extended attribute in order to create or save the object in question.

Editable after creation

This option establishes whether the object saved in the extended attribute can only be modified when saving the object, or whether it can also be modified subsequently.

Value is only managed internally

If this option is activated, the attribute cannot be modified manually, neither at creation time, nor later. This is useful for internal state information configured through a hook function or internally inside a module.


Values of this extended attribute are automatically filled into the form when copying a object.