ansible/test/units/plugins/inventory/test_group.py
AlanCoding 153c9bd539 Reduce recursion within group methods
This offers an optimization that allows loading larger
inventories of various structure by improving the
scaling laws involved for adding hosts and groups.

The primary speed benefit is the elimination of duplicate
recusion from traversing converging paths.
2018-04-05 18:38:44 -04:00

125 lines
4.1 KiB
Python

# Copyright 2018 Alan Rominger <arominge@redhat.com>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible. If not, see <http://www.gnu.org/licenses/>.
from ansible.compat.tests import unittest
from ansible.inventory.group import Group
from ansible.inventory.host import Host
from ansible.errors import AnsibleError
class TestGroup(unittest.TestCase):
def test_depth_update(self):
A = Group('A')
B = Group('B')
Z = Group('Z')
A.add_child_group(B)
A.add_child_group(Z)
self.assertEqual(A.depth, 0)
self.assertEqual(Z.depth, 1)
self.assertEqual(B.depth, 1)
def test_depth_update_dual_branches(self):
alpha = Group('alpha')
A = Group('A')
alpha.add_child_group(A)
B = Group('B')
A.add_child_group(B)
Z = Group('Z')
alpha.add_child_group(Z)
beta = Group('beta')
B.add_child_group(beta)
Z.add_child_group(beta)
self.assertEqual(alpha.depth, 0) # apex
self.assertEqual(beta.depth, 3) # alpha -> A -> B -> beta
omega = Group('omega')
omega.add_child_group(alpha)
# verify that both paths are traversed to get the max depth value
self.assertEqual(B.depth, 3) # omega -> alpha -> A -> B
self.assertEqual(beta.depth, 4) # B -> beta
def test_depth_recursion(self):
A = Group('A')
B = Group('B')
A.add_child_group(B)
# hypothetical of adding B as child group to A
A.parent_groups.append(B)
B.child_groups.append(A)
# can't update depths of groups, because of loop
with self.assertRaises(AnsibleError):
B._check_children_depth()
def test_loop_detection(self):
A = Group('A')
B = Group('B')
C = Group('C')
A.add_child_group(B)
B.add_child_group(C)
with self.assertRaises(AnsibleError):
C.add_child_group(A)
def test_populates_descendant_hosts(self):
A = Group('A')
B = Group('B')
C = Group('C')
h = Host('h')
C.add_host(h)
A.add_child_group(B) # B is child of A
B.add_child_group(C) # C is descendant of A
A.add_child_group(B)
self.assertEqual(set(h.groups), set([C, B, A]))
h2 = Host('h2')
C.add_host(h2)
self.assertEqual(set(h2.groups), set([C, B, A]))
def test_ancestor_example(self):
# see docstring for Group._walk_relationship
groups = {}
for name in ['A', 'B', 'C', 'D', 'E', 'F']:
groups[name] = Group(name)
# first row
groups['A'].add_child_group(groups['D'])
groups['B'].add_child_group(groups['D'])
groups['B'].add_child_group(groups['E'])
groups['C'].add_child_group(groups['D'])
# second row
groups['D'].add_child_group(groups['E'])
groups['D'].add_child_group(groups['F'])
groups['E'].add_child_group(groups['F'])
self.assertEqual(
set(groups['F'].get_ancestors()),
set([
groups['A'], groups['B'], groups['C'], groups['D'], groups['E']
])
)
def test_ancestors_recursive_loop_safe(self):
'''
The get_ancestors method may be referenced before circular parenting
checks, so the method is expected to be stable even with loops
'''
A = Group('A')
B = Group('B')
A.parent_groups.append(B)
B.parent_groups.append(A)
# finishes in finite time
self.assertEqual(A.get_ancestors(), set([A, B]))