Description Sönke Schwardt-Krummrich 2018-09-14 14:20:57 CEST

During implementation a new script creating an UMC portal entry via python UDM, an LDAP object class violation occurred.

An attempt was made to describe the LDAP attribute univentionComputerPortal with a second value on the host object, but this is a single value attribute according to the LDAP schema and therefore an error was returned.

During debugging it turned out that the computer object in settings/portal was not opened correctly. The object is read from LDAP using

compobj = univention.admin.modules.lookup('computers/computer', ....)

and then settings/portal.py checks whether the UDM module used by compobj (here computers/domaincontroller_master) has already been initialized. If not, the univention.admin.modules.init() for the module is done. The host object is then opened via compobj.open().

However, this is not sufficient. During init() the mapping in the domaincontroller_master class is extended for new instances, but the existing instance compobj did not notice this anymore. Probably because of this the property "portal" was not set in open() and was empty.

When the script wrote a value into "portal", the UDM executed an ADD (<empty> → <newvalue>) instead of a REPLACE (<oldvalue> → <newvalue>) for the LDAP attribute, which led to the error message.