From 3b12d76d6064798b15dda0bbd2b66acbec428159 Mon Sep 17 00:00:00 2001
From: Kevin Benton <kevin@benton.pub>
Date: Wed, 30 Aug 2017 20:02:18 -0700
Subject: [PATCH] Pecan: Add missing emulated bulk create method

This adds the simple bulk emulation logic that was present
in the old legacy controller for plugins that do not support
bulk operations.

Closes-Bug: #1714355
Change-Id: I4ff02b9c5c007847edd18ec4ad6794257dd79576
(cherry picked from commit fb76c4f57d7d1cb6e74602d24a166c5d173917e0)
---
 neutron/pecan_wsgi/controllers/resource.py    |  1 -
 neutron/pecan_wsgi/controllers/utils.py       | 32 ++++++++++++++-
 .../functional/pecan_wsgi/test_controllers.py | 41 +++++++++++++++++++
 3 files changed, 71 insertions(+), 3 deletions(-)

diff --git a/neutron/pecan_wsgi/controllers/resource.py b/neutron/pecan_wsgi/controllers/resource.py
index 87379272293..01900bd0d8b 100644
--- a/neutron/pecan_wsgi/controllers/resource.py
+++ b/neutron/pecan_wsgi/controllers/resource.py
@@ -58,7 +58,6 @@ class ItemController(utils.NeutronPecanController):
     def put(self, *args, **kwargs):
         neutron_context = request.context['neutron_context']
         resources = request.context['resources']
-        # TODO(kevinbenton): bulk?
         # Bulk update is not supported, 'resources' always contains a single
         # elemenet
         data = {self.resource: resources[0]}
diff --git a/neutron/pecan_wsgi/controllers/utils.py b/neutron/pecan_wsgi/controllers/utils.py
index 83dd9eaeabc..4d505babe55 100644
--- a/neutron/pecan_wsgi/controllers/utils.py
+++ b/neutron/pecan_wsgi/controllers/utils.py
@@ -18,6 +18,8 @@ import copy
 import functools
 
 from neutron_lib import constants
+from oslo_log import log as logging
+from oslo_utils import excutils
 import pecan
 from pecan import request
 
@@ -28,6 +30,8 @@ from neutron import manager
 
 # Utility functions for Pecan controllers.
 
+LOG = logging.getLogger(__name__)
+
 
 class Fakecode(object):
     co_varnames = ()
@@ -227,8 +231,32 @@ class NeutronPecanController(object):
 
     @property
     def plugin_bulk_creator(self):
-        return getattr(self.plugin,
-                       '%s_bulk' % self._plugin_handlers[self.CREATE])
+        native = getattr(self.plugin,
+                         '%s_bulk' % self._plugin_handlers[self.CREATE],
+                         None)
+        # NOTE(kevinbenton): this flag is just to make testing easier since we
+        # don't have any in-tree plugins without native bulk support
+        if getattr(self.plugin, '_FORCE_EMULATED_BULK', False) or not native:
+            return self._emulated_bulk_creator
+        return native
+
+    def _emulated_bulk_creator(self, context, **kwargs):
+        objs = []
+        body = kwargs[self.collection]
+        try:
+            for item in body[self.collection]:
+                objs.append(self.plugin_creator(context, item))
+            return objs
+        except Exception:
+            with excutils.save_and_reraise_exception():
+                for obj in objs:
+                    try:
+                        self.plugin_deleter(context, obj['id'])
+                    except Exception:
+                        LOG.exception("Unable to undo bulk create for "
+                                      "%(resource)s %(id)s",
+                                      {'resource': self.collection,
+                                       'id': obj['id']})
 
     @property
     def plugin_deleter(self):
diff --git a/neutron/tests/functional/pecan_wsgi/test_controllers.py b/neutron/tests/functional/pecan_wsgi/test_controllers.py
index eb0c218de18..20e63522eeb 100644
--- a/neutron/tests/functional/pecan_wsgi/test_controllers.py
+++ b/neutron/tests/functional/pecan_wsgi/test_controllers.py
@@ -459,6 +459,47 @@ class TestResourceController(TestRootController):
         self.assertIn('ports', json_body)
         self.assertEqual(2, len(json_body['ports']))
 
+    def test_emulated_bulk_create(self):
+        self.plugin._FORCE_EMULATED_BULK = True
+        response = self.app.post_json(
+            '/v2.0/ports.json',
+            params={'ports': [{'network_id': self.port['network_id'],
+                             'admin_state_up': True,
+                             'tenant_id': 'tenid'},
+                             {'network_id': self.port['network_id'],
+                              'admin_state_up': True,
+                              'tenant_id': 'tenid'}]
+                    },
+            headers={'X-Project-Id': 'tenid'})
+        self.assertEqual(response.status_int, 201)
+        json_body = jsonutils.loads(response.body)
+        self.assertIn('ports', json_body)
+        self.assertEqual(2, len(json_body['ports']))
+
+    def test_emulated_bulk_create_rollback(self):
+        self.plugin._FORCE_EMULATED_BULK = True
+        response = self.app.post_json(
+            '/v2.0/ports.json',
+            params={'ports': [{'network_id': self.port['network_id'],
+                             'admin_state_up': True,
+                             'tenant_id': 'tenid'},
+                             {'network_id': self.port['network_id'],
+                              'admin_state_up': True,
+                              'tenant_id': 'tenid'},
+                             {'network_id': 'bad_net_id',
+                              'admin_state_up': True,
+                              'tenant_id': 'tenid'}]
+                    },
+            headers={'X-Project-Id': 'tenid'},
+            expect_errors=True)
+        self.assertEqual(response.status_int, 400)
+        response = self.app.get(
+            '/v2.0/ports.json',
+            headers={'X-Project-Id': 'tenid'})
+        # all ports should be rolled back from above so we are just left
+        # with the one created in setup
+        self.assertEqual(1, len(jsonutils.loads(response.body)['ports']))
+
     def test_bulk_create_one_item(self):
         response = self.app.post_json(
             '/v2.0/ports.json',