Prevent Duplicate VLAN IDs

Addresses Bug 708278

Add check for duplicates in api.py
Add DuplicateVlan to exception.py
Add test to raise DuplicateVlan in test_db_api.py
Add to Authors

Change-Id: I9d68d7b7c886071e38df3c9d7d53724758bdd84c

Authors

@@ -7,6 +7,7 @@ Alex Meade <alex.meade@rackspace.com>
 Alexander Sakhnov <asakhnov@mirantis.com>
 Alvaro Lopez Garcia <aloga@ifca.unican.es>
 Andrew Bogott <abogott@wikimedia.org>
+Andrew Clay Shafer <acs@parvuscaptus.com>
 Andrey Brindeyev <abrindeyev@griddynamics.com>
 Andy Smith <code@term.ie>
 Andy Southgate <andy.southgate@citrix.com>

nova/db/sqlalchemy/api.py

@@ -1984,9 +1984,16 @@ def network_count_reserved_ips(context, network_id):
 
 @require_admin_context
 def network_create_safe(context, values):
+    if values.get('vlan'):
+        if model_query(context, models.Network, read_deleted="no")\
+                      .filter_by(vlan=values['vlan'])\
+                      .first():
+            raise exception.DuplicateVlan(vlan=values['vlan'])
+
     network_ref = models.Network()
     network_ref['uuid'] = str(utils.gen_uuid())
     network_ref.update(values)
+
     try:
         network_ref.save()
         return network_ref

nova/exception.py

@@ -984,3 +984,7 @@ class SolidFireAPIStatusException(SolidFireAPIException):
 
 class SolidFireAPIDataException(SolidFireAPIException):
     message = _("Error in SolidFire API response: data=%(data)s")
+
+
+class DuplicateVlan(Duplicate):
+    message = _("Detected existing vlan with id %(vlan)")

nova/tests/test_db_api.py

@@ -146,6 +146,14 @@ class DbApiTestCase(test.TestCase):
         db_network = db.network_get(ctxt, network.id)
         self.assertEqual(network.uuid, db_network.uuid)
 
+    def test_network_create_with_duplicate_vlan(self):
+        ctxt = context.get_admin_context()
+        values1 = {'host': 'localhost', 'project_id': 'project1', 'vlan': 1}
+        values2 = {'host': 'something', 'project_id': 'project1', 'vlan': 1}
+        db.network_create_safe(ctxt, values1)
+        self.assertRaises(exception.DuplicateVlan,
+                          db.network_create_safe, ctxt, values2)
+
     def test_instance_update_with_instance_id(self):
         """ test instance_update() works when an instance id is passed """
         ctxt = context.get_admin_context()