InventoryDir: refactor logic

Make sure all hosts and groups are unique objects
and that those are referenced uniquely everywhere.
Also fixes test_dir_inventory unit tests which were broken after previous
patches.

	modified:   lib/ansible/inventory/dir.py

lib/ansible/inventory/dir.py

 # (c) 2013, Daniel Hokka Zakrisson <daniel@hozac.com>
+# (c) 2014, Serge van Ginderachter <serge@vanginderachter.be>
 #
 # This file is part of Ansible
 #
@@ -62,31 +63,149 @@ class InventoryDirectory(object):
             else:
                 parser = InventoryParser(filename=fullpath)
             self.parsers.append(parser)
-            # This takes a lot of code because we can't directly use any of the objects, as they have to blend
-            for name, group in parser.groups.iteritems():
-                if name not in self.groups:
-                    self.groups[name] = group
-                else:
-                    # group is already there, copy variables
-                    for k, v in group.get_variables().iteritems():
-                        self.groups[name].set_variable(k, v)
+
+            # retrieve all groups and hosts form the parser and add them to
+            # self, don't look at group lists yet, to avoid
+            # recursion trouble, but just make sure all objects exist in self
+            newgroups = parser.groups.values()
+            for group in newgroups:
                 for host in group.hosts:
+                    self._add_host(host)
+            for group in newgroups:
+                self._add_group(group)
+
+            # now check the objects lists so they contain only objects from
+            # self; membership data in groups is already fine (except all &
+            # ungrouped, see later), but might still reference objects not in self
+            for group in self.groups.values():
+                # iterate on a copy of the lists, as those lists get changed in
+                # the loop
+                # list with group's child group objects:
+                for child in group.child_groups[:]:
+                    if child != self.groups[child.name]:
+                        group.child_groups.remove(child)
+                        group.child_groups.append(self.groups[child.name])
+                # list with group's parent group objects:
+                for parent in group.parent_groups[:]:
+                    if parent != self.groups[parent.name]:
+                        group.parent_groups.remove(parent)
+                        group.parent_groups.append(self.groups[parent.name])
+                # list with group's host objects:
+                for host in group.hosts[:]:
+                    if host != self.hosts[host.name]:
+                        group.hosts.remove(host)
+                        group.hosts.append(self.hosts[host.name])
+                    # also check here that the group that contains host, is
+                    # also contained in the host's group list
+                    if group not in self.hosts[host.name].groups:
+                        self.hosts[host.name].groups.append(group)
+
+        # extra checks on special groups all and ungrouped
+        # remove hosts from 'ungrouped' if they became member of other groups
+        if 'ungrouped' in self.groups:
+            ungrouped = self.groups['ungrouped']
+            # loop on a copy of ungrouped hosts, as we want to change that list
+            for host in ungrouped.hosts[:]:
+                if len(host.groups) > 1:
+                    host.groups.remove(ungrouped)
+                    ungrouped.hosts.remove(host)
+
+        # remove hosts from 'all' if they became member of other groups
+        # all should only contain direct children, not grandchildren
+        # direct children should have dept == 1
+        if 'all' in self.groups:
+            allgroup = self.groups['all' ]
+            # loop on a copy of all's  child groups, as we want to change that list
+            for group in allgroup.child_groups[:]:
+                # groups might once have beeen added to all, and later be added
+                # to another group: we need to remove the link wit all then
+                if len(group.parent_groups) > 1:
+                    # real children of all have just 1 parent, all
+                    # this one has more, so not a direct child of all anymore
+                    group.parent_groups.remove(allgroup)
+                    allgroup.child_groups.remove(group)
+                elif allgroup not in group.parent_groups:
+                    # this group was once added to all, but doesn't list it as
+                    # a parent any more; the info in the group is the correct
+                    # info
+                    allgroup.child_groups.remove(group)
+
+
+    def _add_group(self, group):
+        """ Merge an existing group or add a new one;
+            Track parent and child groups, and hosts of the new one """
+
+        if group.name not in self.groups:
+            # it's brand new, add him!
+            self.groups[group.name] = group
+        if self.groups[group.name] != group:
+            # different object, merge
+            self._merge_groups(self.groups[group.name], group)
+
+    def _add_host(self, host):
         if host.name not in self.hosts:
+            # Papa's got a brand new host
             self.hosts[host.name] = host
+        if self.hosts[host.name] != host:
+            # different object, merge
+            self._merge_hosts(self.hosts[host.name], host)
+
+    def _merge_groups(self, group, newgroup):
+        """ Merge all of instance newgroup into group,
+            update parent/child relationships
+            group lists may still contain group objects that exist in self with
+            same name, but was instanciated as a different object in some other
+            inventory parser; these are handled later """
+
+        # name
+        if group.name != newgroup.name:
+            raise errors.AnsibleError("Cannot merge group %s with %s" % (group.name, newgroup.name))
+
+        # depth
+        group.depth = max([group.depth, newgroup.depth])
+
+        # hosts list (host objects are by now already added to self.hosts)
+        for host in newgroup.hosts:
+            grouphosts = dict([(h.name, h) for h in group.hosts])
+            if host.name in grouphosts:
+                # same host name but different object, merge
+                self._merge_hosts(grouphosts[host.name], host)
             else:
-                        # host is already there, copy variables
-                        # note: depth numbers on duplicates may be bogus
-                        for k, v in host.vars.iteritems():
-                            self.hosts[host.name].set_variable(k, v)
-                    # host can already exist from other source (same name,
-                    # different object):
-                    if host.name not in [h.name for h in self.groups[name].hosts]:
-                        self.groups[name].add_host(self.hosts[host.name])
-
-            # This needs to be a second loop to ensure all the parent groups exist
-            for name, group in parser.groups.iteritems():
-                for parent in group.parent_groups:
-                    self.groups[parent.name].add_child_group(self.groups[name])
+                # new membership
+                group.add_host(self.hosts[host.name])
+
+        # group child membership relation
+        for newchild in newgroup.child_groups:
+            # dict with existing child groups:
+            childgroups = dict([(g.name, g) for g in group.child_groups])
+            # check if child of new group is already known as a child
+            if newchild.name not in childgroups:
+                self.groups[group.name].add_child_group(newchild)
+
+        # group parent membership relation
+        for newparent in newgroup.parent_groups:
+            # dict with existing parent groups:
+            parentgroups = dict([(g.name, g) for g in group.parent_groups])
+            # check if parent of new group is already known as a parent
+            if newparent.name not in parentgroups:
+                if newparent.name not in self.groups:
+                    # group does not exist yet in self, import him
+                    self.groups[newparent.name] = newparent
+                # group now exists but not yet as a parent here
+                self.groups[newparent.name].add_child_group(group)
+
+        # variables
+        group.vars = utils.combine_vars(group.vars, newgroup.vars)
+
+    def _merge_hosts(self,host, newhost):
+        """ Merge all of instance newhost into host """
+
+        # name
+        if host.name != newhost.name:
+            raise errors.AnsibleError("Cannot merge host %s with %s" % (host.name, newhost.name))
+
+        # variables
+        host.vars = utils.combine_vars(host.vars, newhost.vars)
 
     def get_host_variables(self, host):
         """ Gets additional host variables from all inventories """

test/units/TestInventory.py

@@ -425,7 +425,7 @@ class TestInventory(unittest.TestCase):
 
         expected_vars = {'inventory_hostname': 'zeus',
                          'inventory_hostname_short': 'zeus',
-                         'group_names': ['greek', 'major-god', 'ungrouped'],
+                         'group_names': ['greek', 'major-god'],
                          'var_a': '3#4'}
 
         print "HOST     VARS=%s" % host_vars