cubicweb/misc/scripts/detect_cycle.py
author Philippe Pepiot <philippe.pepiot@logilab.fr>
Tue, 17 Mar 2020 13:31:50 +0100
branch3.27
changeset 12916 7d67f69ebe88
parent 11057 0b59724cb3f2
permissions -rw-r--r--
[pkg] add python3 only pypi specifiers This is only for pypi statistics purposes. Also add 'Programming Language :: Python', looks obvious but seems to be sane to have this as well.

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))