simplify query building logic

as a side-effect we now have fakeldap with support for '&' queries with
a single filter(e.g. "(&(myfilter=true))" )

Change-Id: I29564704f58e108cbfb488c18e1dfd4656e1d18c

2 files changed, 12 insertions, 18 deletions

diff --git a/keystone/common/ldap/core.py b/keystone/common/ldap/core.py
index e767e93e..aab42a20 100644
--- a/keystone/common/ldap/core.py
+++ b/keystone/common/ldap/core.py
@@ -204,11 +204,8 @@ class BaseLdap(object):
 
     def _ldap_get(self, id, filter=None):
         conn = self.get_connection()
-        query = '(objectClass=%s)' % self.object_class
-        if (filter is not None or self.filter is not None):
-            localfilter = self.filter if self.filter is not None else ''
-            paramfilter = filter if filter is not None else ''
-            query = '(&%s%s%s)' % (localfilter, paramfilter, query)
+        query = '(&%s(objectClass=%s))' % (filter or self.filter or '',
+                                           self.object_class)
         try:
             res = conn.search_s(self._id_to_dn(id), ldap.SCOPE_BASE, query)
         except ldap.NO_SUCH_OBJECT:
@@ -221,11 +218,8 @@ class BaseLdap(object):
 
     def _ldap_get_all(self, filter=None):
         conn = self.get_connection()
-        query = '(objectClass=%s)' % (self.object_class,)
-        if (filter is not None or self.filter is not None):
-            localfilter = self.filter if self.filter is not None else ''
-            paramfilter = filter if filter is not None else ''
-            query = '(&%s%s%s)' % (localfilter, paramfilter, query)
+        query = '(&%s(objectClass=%s))' % (filter or self.filter or '',
+                                           self.object_class)
         try:
             return conn.search_s(self.tree_dn, ldap.SCOPE_ONELEVEL, query)
         except ldap.NO_SUCH_OBJECT:
diff --git a/keystone/common/ldap/fakeldap.py b/keystone/common/ldap/fakeldap.py
index b41f20d5..43490bef 100644
--- a/keystone/common/ldap/fakeldap.py
+++ b/keystone/common/ldap/fakeldap.py
@@ -51,14 +51,14 @@ def _match_query(query, attrs):
     """
     # cut off the parentheses
     inner = query[1:-1]
-    if inner.startswith('&'):
-        # cut off the &
-        l, r = _paren_groups(inner[1:])
-        return _match_query(l, attrs) and _match_query(r, attrs)
-    if inner.startswith('|'):
-        # cut off the |
-        l, r = _paren_groups(inner[1:])
-        return _match_query(l, attrs) or _match_query(r, attrs)
+    if inner.startswith(('&', '|')):
+        # cut off the & or |
+        groups = _paren_groups(inner[1:])
+        try:
+            l, r = groups
+            return _match_query(l, attrs) and _match_query(r, attrs)
+        except ValueError:  # just one group
+            return _match_query(groups[0], attrs)
     if inner.startswith('!'):
         # cut off the ! and the nested parentheses
         return not _match_query(query[2:-1], attrs)