Reduce domain specific config setup duplication

The test setup was creating and recreating the databases and loading
them with fixture data several times for each test run. Locally this
patch cut the test run times for these tests by about 70%.

Change-Id: I8caae6e9b30254b843e9325659df358a321ab840

keystone/tests/unit/test_backend_ldap.py

@@ -3012,33 +3012,26 @@ class DomainSpecificLDAPandSQLIdentity(
 
     """
 
+    DOMAIN_COUNT = 2
+    DOMAIN_SPECIFIC_COUNT = 2
+
     def setUp(self):
-        sqldb = self.useFixture(database.Database())
+        self.domain_count = self.DOMAIN_COUNT
+        self.domain_specific_count = self.DOMAIN_SPECIFIC_COUNT
+
+        self.useFixture(database.Database())
         super(DomainSpecificLDAPandSQLIdentity, self).setUp()
-        self.initial_setup(sqldb)
+        self.assert_backends()
 
-    def initial_setup(self, sqldb):
-        # We aren't setting up any initial data ahead of switching to
-        # domain-specific operation, so make the switch straight away.
-        self.config_fixture.config(
-            group='identity', domain_specific_drivers_enabled=True,
-            domain_config_dir=(
-                unit.TESTCONF + '/domain_configs_one_sql_one_ldap'))
-        self.config_fixture.config(group='identity_mapping',
-                                   backward_compatible_ids=False)
-
-        self.load_backends()
-        sqldb.recreate()
-
-        self.domain_count = 2
-        self.domain_specific_count = 2
+    def load_fixtures(self, fixtures):
         self.setup_initial_domains()
-        self.users = {}
 
-        self.ldapdb.clear()
-        self.load_fixtures(default_fixtures)
+        super(DomainSpecificLDAPandSQLIdentity, self).load_fixtures(fixtures)
+
+        self.users = {}
         self.create_users_across_domains()
 
+    def assert_backends(self):
         _assert_backends(
             self,
             assignment='sql',
@@ -3056,6 +3049,16 @@ class DomainSpecificLDAPandSQLIdentity(
         self.config_fixture.config(group='resource', driver='sql')
         self.config_fixture.config(group='assignment', driver='sql')
 
+        # We aren't setting up any initial data ahead of switching to
+        # domain-specific operation, so make the switch straight away.
+        self.config_fixture.config(
+            group='identity', domain_specific_drivers_enabled=True,
+            domain_config_dir=(
+                unit.TESTCONF + '/domain_configs_one_sql_one_ldap'))
+
+        self.config_fixture.config(group='identity_mapping',
+                                   backward_compatible_ids=False)
+
     def get_config(self, domain_id):
         # Get the config for this domain, will return CONF
         # if no specific config defined for this domain
@@ -3204,30 +3207,10 @@ class DomainSpecificSQLIdentity(DomainSpecificLDAPandSQLIdentity):
 
     """
 
-    def initial_setup(self, sqldb):
-        # We aren't setting up any initial data ahead of switching to
-        # domain-specific operation, so make the switch straight away.
-        self.config_fixture.config(
-            group='identity', domain_specific_drivers_enabled=True,
-            domain_config_dir=(
-                unit.TESTCONF + '/domain_configs_default_ldap_one_sql'))
-        # Part of the testing counts how many new mappings get created as
-        # we create users, so ensure we are NOT using mapping for the default
-        # LDAP domain so this doesn't confuse the calculation.
-        self.config_fixture.config(group='identity_mapping',
-                                   backward_compatible_ids=True)
-
-        self.load_backends()
-        sqldb.recreate()
-
-        self.domain_count = 2
-        self.domain_specific_count = 1
-        self.setup_initial_domains()
-        self.users = {}
-
-        self.load_fixtures(default_fixtures)
-        self.create_users_across_domains()
+    DOMAIN_COUNT = 2
+    DOMAIN_SPECIFIC_COUNT = 1
 
+    def assert_backends(self):
         _assert_backends(self,
                          assignment='sql',
                          identity='ldap',
@@ -3236,8 +3219,19 @@ class DomainSpecificSQLIdentity(DomainSpecificLDAPandSQLIdentity):
     def config_overrides(self):
         super(DomainSpecificSQLIdentity, self).config_overrides()
         self.config_fixture.config(group='identity', driver='ldap')
-        self.config_fixture.config(group='resource', driver='sql')
-        self.config_fixture.config(group='assignment', driver='sql')
+
+        # We aren't setting up any initial data ahead of switching to
+        # domain-specific operation, so make the switch straight away.
+        self.config_fixture.config(
+            group='identity', domain_specific_drivers_enabled=True,
+            domain_config_dir=(
+                unit.TESTCONF + '/domain_configs_default_ldap_one_sql'))
+
+        # Part of the testing counts how many new mappings get created as
+        # we create users, so ensure we are NOT using mapping for the default
+        # LDAP domain so this doesn't confuse the calculation.
+        self.config_fixture.config(group='identity_mapping',
+                                   backward_compatible_ids=True)
 
     def get_config(self, domain_id):
         if domain_id == CONF.identity.default_domain_id: