Description Daniel Tröder 2021-03-18 10:29:09 CET

The UDM CLI handles it robustly:
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root@m20:~# udm users/user list --filter uid=Administrator | grep phone
root@m20:~# udm users/user modify --dn uid=Administrator,cn=users,dc=uni,dc=dtr --append phone=123 
Object modified: uid=Administrator,cn=users,dc=uni,dc=dtr
root@m20:~# udm users/user list --filter uid=Administrator | grep phone
  phone: 123
root@m20:~# udm users/user modify --dn uid=Administrator,cn=users,dc=uni,dc=dtr --append phone=123 
WARNING: cannot append 123 to phone, value exists
No modification: uid=Administrator,cn=users,dc=uni,dc=dtr
root@m20:~# udm users/user modify --dn uid=Administrator,cn=users,dc=uni,dc=dtr --append phone=456 --append phone=123 
WARNING: cannot append 123 to phone, value exists
Object modified: uid=Administrator,cn=users,dc=uni,dc=dtr
root@m20:~# udm users/user list --filter uid=Administrator | grep phone
  phone: 123
  phone: 456
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The UDM Python lib also:
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root@m20:~# python
>>> from univention.udm import UDM
>>> user_mod = UDM.admin().version(0).get('users/user')
>>> user = user_mod.get("uid=Administrator,cn=users,dc=uni,dc=dtr")
>>> user.props.phone
['123', '456']
>>> user.props.phone.append("123")
>>> user.save()
>>> user = user_mod.get("uid=Administrator,cn=users,dc=uni,dc=dtr")
>>> user.props.phone
['123', '456']
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But the UMC module shows an error popup when saving a duplicate phone entry:
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Das LDAP-Objekt konnte nicht gespeichert werden: LDAP-Fehler Type or value exists: telephoneNumber: value #0 provided more than once
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This behavior cannot be observed when saving duplicate "departmentNumber" entries.

The UMC should handle duplicate entries in the multi value field "email" robustly.