Problem: Installing itslearning in UMC stuck or fails with "Cannot read itslearning/SAML_FQDN"

Problem

When the app is installed via the UMC, the installation gets stuck in:

“Bitte warten, bis die Aktion durchgeführt wurde”
“Please wait until the action has been performed”

itslearning_error

Investigation

tail -n 50 /var/log/univention/appcenter.log

--------------------------------
38290 utils                            21-09-13 17:18:22 [   DEBUG]:
send_information: action=search app=None value=its status=200
  38290 utils                            21-09-13 17:18:22 [   DEBUG]:
tracking information: {'action': 'search', 'status': 200, 'role':
'domaincontroller_master', 'uuid':
'00000000-0000-0000-0000-000000000000', 'value': u'its'}
  38290 utils                            21-09-13 17:18:23 [   DEBUG]:
send_information: action=search app=None value=itslea status=200
  38290 utils                            21-09-13 17:18:23 [   DEBUG]:
tracking information: {'action': 'search', 'status': 200, 'role':
'domaincontroller_master', 'uuid':
'00000000-0000-0000-0000-000000000000', 'value': u'itslea'}
  38290 utils                            21-09-13 17:18:23 [   DEBUG]:
send_information: action=get app=itslearning value=None status=200
  38290 utils                            21-09-13 17:18:23 [   DEBUG]:
tracking information: {'status': 200, 'uuid':
'65498915-c83b-4e23-a803-4f05e671813c', 'app': 'itslearning', 'version':
'3.2', 'role': 'domaincontroller_master', 'action': 'get',
'system-uuid': '9b37998c-6d73-494c-b957-a8faa6fdc686'}
  38290 settings                         21-09-13 17:18:26 [    INFO]:
Cannot read myapp/myfile while itslearning=3.2 is not running
  38290 settings                         21-09-13 17:18:26 [    INFO]:
Falling back to initial value for myapp/myfile
  38290 settings                         21-09-13 17:18:26 [    INFO]:
Cannot read itslearning/SAML_FQDN while itslearning=3.2 is not running
  38290 settings                         21-09-13 17:18:26 [    INFO]:
Cannot use None for itslearning/SAML_FQDN
  38290 settings                         21-09-13 17:18:26 [    INFO]:
Falling back to initial value for itslearning/SAML_FQDN
-----------------------------------

Solution

Use the CLI:

univention-app install itslearning --set itslearning/SAML_FQDN=YOUR.SAML_FQDN.FOO