misc/scripts/detect_cycle.py
author Julien Cristau <julien.cristau@logilab.fr>
Thu, 10 Apr 2014 15:03:01 +0200
changeset 9680 8fb8f001f4e2
parent 6198 f8dea560703f
child 10589 7c23b7de2b8d
permissions -rw-r--r--
[hooks] run cascading delete hook later Applications may have their own before_delete_entity hooks that rely on the composite relations still existing.


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)