[web/facet] Use an Exists node in HasRelationFacet
The generated RQL now includes an EXISTS clause. For instance, one gets:
::
DISTINCT Any WHERE X is CWUser, EXISTS(X in_group A)
instead of:
::
DISTINCT Any WHERE X is CWUser, X in_group A
for a HasRelationFacet with ``rtype = 'in_group'``, which is more appropriate
for testing the existence of the relation.
Add a test for this facet along the way.
from base64 import b64decode, b64encode
try:
uri, newdn = __args__
except ValueError:
print 'USAGE: cubicweb-ctl shell <instance> ldap_change_base_dn.py -- <ldap source uri> <new dn>'
print
print 'you should not have updated your sources file yet'
olddn = repo.sources_by_uri[uri].config['user-base-dn']
assert olddn != newdn
raw_input("Ensure you've stopped the instance, type enter when done.")
for eid, extid in sql("SELECT eid, extid FROM entities WHERE source='%s'" % uri):
olduserdn = b64decode(extid)
newuserdn = olduserdn.replace(olddn, newdn)
if newuserdn != olduserdn:
print olduserdn, '->', newuserdn
sql("UPDATE entities SET extid='%s' WHERE eid=%s" % (b64encode(newuserdn), eid))
commit()
print 'you can now update the sources file to the new dn and restart the instance'