Fix for bug 902175

Remove the gateway port when deleting the network (if it's the only one left),
and kill dnsmasq if the network is deleted.

Change-Id: If6b4798ddb4d21fe6c32ac20e6237494b799ecbd

3 files changed, 46 insertions, 6 deletions

diff --git a/nova/network/quantum/manager.py b/nova/network/quantum/manager.py
index 9b6741e92..0ea2a5a50 100644
--- a/nova/network/quantum/manager.py
+++ b/nova/network/quantum/manager.py
@@ -137,6 +137,9 @@ class QuantumManager(manager.FlatManager):
 
         return [{'uuid': quantum_net_id}]
 
+    def _generate_gw_dev(self, network_id):
+        return "gw-" + str(network_id[0:11])
+
     def delete_network(self, context, fixed_range, uuid):
         """Lookup network by uuid, delete both the IPAM
            subnet and the corresponding Quantum network.
@@ -149,11 +152,28 @@ class QuantumManager(manager.FlatManager):
         if project_id is None:
             # If nothing was found we default to this
             project_id = FLAGS.quantum_default_tenant_id
+        q_tenant_id = project_id or FLAGS.quantum_default_tenant_id
+        # Check for any attached ports on the network and fail the deletion if
+        # there is anything but the gateway port attached.  If it is only the
+        # gateway port, unattach and delete it.
+        ports = self.q_conn.get_attached_ports(q_tenant_id, quantum_net_id)
+        if len(ports) > 1:
+            raise Exception(_("Network %s in use, cannot delete" %
+                              (quantum_net_id)))
+        LOG.debug("Ports currently on network: %s" % ports)
+        for p in ports:
+            if p["attachment"].startswith("gw-"):
+                self.q_conn.detach_and_delete_port(q_tenant_id,
+                                                   quantum_net_id,
+                                                   p['port-id'])
+        # Now we can delete the network
+        self.q_conn.delete_network(q_tenant_id, quantum_net_id)
         LOG.debug("Deleting network for tenant: %s" % project_id)
         self.ipam.delete_subnets_by_net_id(context, quantum_net_id,
                 project_id)
-        q_tenant_id = project_id or FLAGS.quantum_default_tenant_id
-        self.q_conn.delete_network(q_tenant_id, quantum_net_id)
+        # Get rid of dnsmasq
+        dev = self._generate_gw_dev(quantum_net_id)
+        self.driver.kill_dhcp(dev)
 
     def allocate_for_instance(self, context, **kwargs):
         """Called by compute when it is creating a new VM.
@@ -495,7 +515,7 @@ class QuantumManager(manager.FlatManager):
             network_ref['dhcp_start'] = IPAddress(n.first + 2)
             network_ref['broadcast'] = IPAddress(n.broadcast)
             network_ref['gateway'] = IPAddress(n.first + 1)
-            dev = "gw-" + str(network_ref['uuid'][0:11])
+            dev = self._generate_gw_dev(network_ref['uuid'])
             # And remove the dhcp mappings for the subnet
             hosts = self.get_dhcp_hosts_text(context,
                 subnet['network_id'], project_id)
@@ -504,9 +524,6 @@ class QuantumManager(manager.FlatManager):
             self.driver.kill_dhcp(dev)
             self.driver.restart_dhcp(context, dev, network_ref)
 
-            # TODO(bgh): if this is the last instance for the network
-            # then we should actually just kill the dhcp server.
-
     def validate_networks(self, context, networks):
         """Validates that this tenant has quantum networks with the associated
            UUIDs.  This is called by the 'os-create-server-ext' API extension
diff --git a/nova/network/quantum/quantum_connection.py b/nova/network/quantum/quantum_connection.py
index 91c98797c..36c1a1986 100644
--- a/nova/network/quantum/quantum_connection.py
+++ b/nova/network/quantum/quantum_connection.py
@@ -123,3 +123,17 @@ class QuantumClientConnection(object):
             if attachment_id == port_get_resdict["attachment"]["id"]:
                 return port_id
         return None
+
+    def get_attached_ports(self, tenant_id, network_id):
+        rv = []
+        port_list = self.client.list_ports(network_id, tenant=tenant_id)
+        for p in port_list["ports"]:
+            port_id = p["id"]
+            port = self.client.show_port_attachment(network_id,
+                                port_id, tenant=tenant_id)
+            # Skip ports without an attachment
+            if "id" not in port["attachment"]:
+                continue
+            rv.append({'port-id': port_id, 'attachment':
+                       port["attachment"]["id"]})
+        return rv
diff --git a/nova/tests/test_quantum.py b/nova/tests/test_quantum.py
index 174c512db..37a3ea465 100644
--- a/nova/tests/test_quantum.py
+++ b/nova/tests/test_quantum.py
@@ -104,6 +104,15 @@ class FakeQuantumClientConnection(object):
                         return port_id
         return None
 
+    def get_attached_ports(self, tenant_id, net_id):
+        ports = []
+        for nid, n in self.nets.items():
+            if nid == net_id and n['tenant-id'] == tenant_id:
+                for port_id, p in n['ports'].items():
+                    ports.append({'port-id': port_id,
+                            'attachment': p['attachment-id']})
+        return ports
+
     def get_networks(self, tenant_id):
         nets = []
         for nid, n in self.nets.items():