[server] improve TZDatetime support
by depending on logilab-database 1.15.0 including
https://www.logilab.org/ticket/1485893, we can now keep the tzinfo
attribute on datetime objects for TZDatetime attributes, so one knows
that this is a tz-aware datetime.
To easily make it work with backends that have no tz support, we keep
converting tz-aware datetime objects into utc naive datetime objects
before sending them to the database.
from __future__ import print_function
try:
rtype, = __args__
except ValueError:
print('USAGE: cubicweb-ctl shell <instance> detect_cycle.py -- <relation type>')
print()
graph = {}
for fromeid, toeid in rql('Any X,Y WHERE X %s Y' % rtype):
graph.setdefault(fromeid, []).append(toeid)
from logilab.common.graph import get_cycles
for cycle in get_cycles(graph):
print('cycle', '->'.join(str(n) for n in cycle))