misc/scripts/detect_cycle.py
author Denis Laxalde <denis.laxalde@logilab.fr>
Mon, 30 Nov 2015 11:09:51 +0100
changeset 10939 b30c2f49da57
parent 10589 7c23b7de2b8d
permissions -rw-r--r--
[dataimport] Format strings with % instead of .format() For consistency with CubicWeb code base and to avoid Python 2.6 compatibility traps.

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))