Get rid of backslash continuations in code

Continuing lines with backslashes is considered icky in python. However,
sqla's function chaining lends itself to doing that, so we had some
backslash continuations in placement. This commit removes them and
reformats the code accordingly.

Change-Id: I703d3ec3ae88c93b9ad2cf48a59642353f8628ce

placement/conf/opts.py

@@ -63,9 +63,9 @@ def _import_modules(module_names):
     for modname in module_names:
         mod = importlib.import_module("placement.conf." + modname)
         if not hasattr(mod, LIST_OPTS_FUNC_NAME):
-            msg = "The module 'placement.conf.%s' should have a '%s' "\
-                  "function which returns the config options." % \
-                  (modname, LIST_OPTS_FUNC_NAME)
+            msg = ("The module 'placement.conf.%s' should have a '%s' "
+                   "function which returns the config options." %
+                   (modname, LIST_OPTS_FUNC_NAME))
             raise Exception(msg)
         else:
             imported_modules.append(mod)

placement/objects/resource_provider.py

@@ -279,8 +279,9 @@ def _update_inventory_for_provider(ctx, rp, inv_list, to_update):
         rc_str = rc_cache.RC_CACHE.string_from_id(rc_id)
         inv_record = inv_list.find(rc_str)
         allocation_query = sa.select(
-            [func.sum(_ALLOC_TBL.c.used).label('usage')]).\
-            where(sa.and_(
+            [func.sum(_ALLOC_TBL.c.used).label('usage')])
+        allocation_query = allocation_query.where(
+            sa.and_(
                 _ALLOC_TBL.c.resource_provider_id == rp.id,
                 _ALLOC_TBL.c.resource_class_id == rc_id))
         allocations = ctx.session.execute(allocation_query).first()
@@ -941,9 +942,9 @@ def _provider_ids_matching_aggregates(context, member_of, rp_ids=None):
 
 @db_api.placement_context_manager.writer
 def _delete_rp_record(context, _id):
-    return context.session.query(models.ResourceProvider).\
-        filter(models.ResourceProvider.id == _id).\
-        delete(synchronize_session=False)
+    query = context.session.query(models.ResourceProvider)
+    query = query.filter(models.ResourceProvider.id == _id)
+    return query.delete(synchronize_session=False)
 
 
 class ResourceProvider(object):
@@ -1153,9 +1154,9 @@ class ResourceProvider(object):
         if rp_allocations:
             raise exception.ResourceProviderInUse()
         # Delete any inventory associated with the resource provider
-        context.session.query(models.Inventory).\
-            filter(models.Inventory.resource_provider_id == _id).\
-            delete(synchronize_session=False)
+        query = context.session.query(models.Inventory)
+        query = query.filter(models.Inventory.resource_provider_id == _id)
+        query.delete(synchronize_session=False)
         # Delete any aggregate associations for the resource provider
         # The name substitution on the next line is needed to satisfy pep8
         RPA_model = models.ResourceProviderAggregate
@@ -1166,10 +1167,11 @@ class ResourceProvider(object):
         context.session.query(RPT_model).filter(
             RPT_model.resource_provider_id == _id).delete()
         # set root_provider_id to null to make deletion possible
-        context.session.query(models.ResourceProvider).\
-            filter(models.ResourceProvider.id == _id,
-                   models.ResourceProvider.root_provider_id == _id).\
-            update({'root_provider_id': None})
+        query = context.session.query(models.ResourceProvider)
+        query = query.filter(
+            models.ResourceProvider.id == _id,
+            models.ResourceProvider.root_provider_id == _id)
+        query.update({'root_provider_id': None})
         # Now delete the RP record
         try:
             result = _delete_rp_record(context, _id)

placement/tests/functional/db/test_migrations.py

@@ -136,8 +136,7 @@ class TestWalkVersions(testtools.TestCase, WalkVersionsMixin):
 class MigrationCheckersMixin(object):
     def setUp(self):
         super(MigrationCheckersMixin, self).setUp()
-        self.engine = db_api.placement_context_manager.\
-            writer.get_engine()
+        self.engine = db_api.placement_context_manager.writer.get_engine()
         self.config = migration._alembic_config()
         self.migration_api = migration
 

placement/tests/functional/db/test_resource_provider.py

@@ -503,10 +503,9 @@ class ResourceProviderTestCase(tb.PlacementDbBaseTestCase):
 
         def emulate_rp_mysql_delete(func):
             def wrapped(context, _id):
-                rp = context.session.query(
-                    models.ResourceProvider).\
-                    filter(
-                        models.ResourceProvider.id == _id).first()
+                query = context.session.query(models.ResourceProvider)
+                query = query.filter(models.ResourceProvider.id == _id)
+                rp = query.first()
                 self.assertIsNone(rp.root_provider_id)
                 return func(context, _id)
             return wrapped