[PATCH v2 4/4] SlavePool: sort machines and interfaces in matching algorithm

[Jan Tluka]

We want to have matching algorithm deterministic. For that we need to
secure, that data are entered in the same order each time. This patch
adds sorting of machines by their id's before they enter matching algorithm
so it shouldn't happen that for same setup, machines are mapped differently
in more runs

Version 2: Sort also interfaces and use reverse sorting just to make sure
we're processing the hostnames and interfaces in alphabetical order
while matching.

Signed-off-by: Jiri Prochazka <jprochaz(a)redhat.com&gt;
Signed-off-by: Jan Tluka <jtluka(a)redhat.com&gt;
---
 lnst/Controller/SlavePool.py | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/lnst/Controller/SlavePool.py b/lnst/Controller/SlavePool.py
index 21dd3e7..87bc850 100644
--- a/lnst/Controller/SlavePool.py
+++ b/lnst/Controller/SlavePool.py
@@ -402,7 +402,7 @@ class SetupMapper(object):
     def reset_match_state(self):
         self._net_label_mapping = {}
         self._machine_stack = []
-        self._unmatched_req_machines = self._mreqs.keys()
+        self._unmatched_req_machines = sorted(self._mreqs.keys(), reverse=True)
 
         self._pool_stack = list(self._pools.keys())
         if len(self._pool_stack) > 0:
@@ -410,7 +410,7 @@ class SetupMapper(object):
             self._pool = self._pools[self._pool_name]
 
         self._unmatched_pool_machines = []
-        for p_id, p_machine in self._pool.iteritems():
+        for p_id, p_machine in sorted(self._pool.iteritems(), reverse=True):
             if self._virtual_matching:
                 if "libvirt_domain" in p_machine["params"]:
                     self._unmatched_pool_machines.append(p_id)
@@ -450,9 +450,9 @@ class SetupMapper(object):
                     if self._check_machine_compatibility(mreq_m_id, pool_m_id):
                         #map compatible pool machine
                         stack_top["current_match"] = pool_m_id
-                        pool_ifs = self._pool[pool_m_id]["interfaces"].keys()
-                        stack_top["unmatched_pool_ifs"] = list(pool_ifs)
-
+                        stack_top["unmatched_pool_ifs"] = \
+                            sorted(self._pool[pool_m_id]["interfaces"].keys(),
+                                   reverse=True)
                         self._unmatched_pool_machines.remove(pool_m_id)
                         break
 
@@ -475,7 +475,7 @@ class SetupMapper(object):
                                      self._pool_name)
 
                         self._unmatched_pool_machines = []
-                        for p_id, p_machine in self._pool.iteritems():
+                        for p_id, p_machine in sorted(self._pool.iteritems(),
reverse=True):
                             if self._virtual_matching:
                                 if "libvirt_domain" in
p_machine["params"]:
                                     self._unmatched_pool_machines.append(p_id)
@@ -550,7 +550,8 @@ class SetupMapper(object):
         machine_match["if_stack"] = []
 
         machine = self._mreqs[machine_match["m_id"]]
-        machine_match["unmatched_ifs"] =
machine["interfaces"].keys()
+        machine_match["unmatched_ifs"] =
sorted(machine["interfaces"].keys(),
+                                                reverse=True)
         machine_match["unmatched_pool_ifs"] = []
 
         if self._virtual_matching:
-- 
2.4.3