Fix potential issue with network/subnet name length.

In OpenStack Neutron and Octavia, name and descriptions of the objects
are limited to the 255 characters, while on Kubernetes names are limited
to the 253 characters. Kuryr often creates names for the networks and
subnets using Kubernetes object name with additional prefix and suffix,
which may exceed allowed character limit. In this patch there is
proposed solution for this issue by simply truncate kubernetes resource
name, while keeping prefix and suffix intact, to fit the Neutron name
limit.

Change-Id: I6e404104034f11593fc313797ad464458bbdf82d

kuryr_kubernetes/controller/drivers/lbaasv2.py

@@ -26,6 +26,7 @@ from kuryr_kubernetes import clients
 from kuryr_kubernetes import config
 from kuryr_kubernetes import constants as k_const
 from kuryr_kubernetes.controller.drivers import base
+from kuryr_kubernetes.controller.drivers import utils as c_utils
 from kuryr_kubernetes import exceptions as k_exc
 from kuryr_kubernetes import utils
 
@@ -868,7 +869,8 @@ class LBaaSv2Driver(base.LBaaSDriver):
         svc_name = service['metadata']['name']
         svc_ports = service['spec'].get('ports', [])
 
-        lbaas_name = "%s/%s" % (svc_namespace, svc_name)
+        lbaas_name = c_utils.get_resource_name(svc_name,
+                                               prefix=svc_namespace + "/")
 
         endpoints_link = utils.get_endpoints_link(service)
         k8s = clients.get_kubernetes_client()
@@ -913,7 +915,9 @@ class LBaaSv2Driver(base.LBaaSDriver):
             port_protocol = port['protocol']
             lbaas_port = port['port']
             target_port = port['targetPort']
-            sg_rule_name = "%s:%s:%s" % (lbaas_name, port_protocol, lbaas_port)
+            suffix = f"{port_protocol}:{lbaas_port}"
+            sg_rule_name = c_utils.get_resource_name(lbaas_name,
+                                                     suffix=':' + suffix)
             listener_id = lsnr_ids.get((port_protocol, lbaas_port))
             if listener_id is None:
                 LOG.warning("There is no listener associated to the protocol "

kuryr_kubernetes/controller/drivers/namespace_subnet.py

@@ -119,7 +119,8 @@ class NamespacePodSubnetDriver(default_subnet.DefaultPodSubnetDriver):
 
     def create_network(self, ns_name, project_id):
         os_net = clients.get_network_client()
-        net_name = 'ns/' + ns_name + '-net'
+        net_name = c_utils.get_resource_name(ns_name, prefix='ns/',
+                                             suffix='-net')
         tags = oslo_cfg.CONF.neutron_defaults.resource_tags
         if tags:
             networks = os_net.networks(name=net_name, tags=tags)
@@ -148,7 +149,8 @@ class NamespacePodSubnetDriver(default_subnet.DefaultPodSubnetDriver):
 
     def create_subnet(self, ns_name, project_id, net_id):
         os_net = clients.get_network_client()
-        subnet_name = "ns/" + ns_name + "-subnet"
+        subnet_name = c_utils.get_resource_name(ns_name, prefix='ns/',
+                                                suffix='-subnet')
         tags = oslo_cfg.CONF.neutron_defaults.resource_tags
         if tags:
             subnets = os_net.subnets(name=subnet_name, tags=tags)

kuryr_kubernetes/controller/drivers/network_policy.py

@@ -54,8 +54,10 @@ class NetworkPolicyDriver(base.NetworkPolicyDriver):
             return self.namespaced_pods(policy)
 
     def create_security_group(self, knp, project_id):
-        sg_name = ("sg-" + knp['metadata']['namespace'] + "-" +
-                   knp['metadata']['name'])
+        sg_name = driver_utils.get_resource_name(knp['metadata']['namespace'] +
+                                                 '-' +
+                                                 knp['metadata']['name'],
+                                                 prefix='sg/')
         desc = ("Kuryr-Kubernetes Network Policy %s SG" %
                 utils.get_res_unique_name(knp))
         try:

kuryr_kubernetes/controller/drivers/utils.py

@@ -50,7 +50,8 @@ def get_network_id(subnets):
 
 
 def get_port_name(pod):
-    return "%(namespace)s/%(name)s" % pod['metadata']
+    return get_resource_name(pod['metadata']['name'],
+                             prefix=pod['metadata']['namespace'] + "/")
 
 
 def get_device_id(pod):
@@ -749,3 +750,23 @@ def delete_port(leftover_port):
                           "continue with the other "
                           "rest.", leftover_port.id)
     return False
+
+
+def get_resource_name(name, prefix='', suffix=''):
+    """Get OpenStack resource name out of Kubernetes resources
+
+    Return name for the OpenStack resource, which usually is up to 255 chars
+    long. And while Kubernetes allows to set resource names up to 253
+    characters, that makes a risk to have too long name. This function will
+    prefix and suffix over name of the k8s resource, which will get truncated
+    if needed.
+
+    https://kubernetes.io/docs/concepts/overview/working-with-objects/names/
+    """
+
+    length = len(f'{prefix}{name}{suffix}')
+
+    if length > 255:
+        name = name[:254-(length-254)]
+
+    return f'{prefix}{name}{suffix}'

kuryr_kubernetes/tests/unit/controller/drivers/test_utils.py

@@ -115,3 +115,48 @@ class TestUtils(test_base.TestCase):
                         group='kubernetes')
 
         self.assertTrue(utils.is_network_policy_enabled())
+
+    def test_get_resource_name_with_too_long_name(self):
+        name = 253 * "a"
+        prefix = 'ns/'
+        suffix = '-net'
+
+        new_name = utils.get_resource_name(name, prefix, suffix)
+
+        self.assertEqual(new_name,
+                         prefix + 248 * 'a' + suffix)
+        self.assertEqual(len(new_name), 255)
+
+    def test_get_resource_name_with_sane_name(self):
+        name = 'myns'
+        prefix = 'ns/'
+        suffix = '-foo'
+
+        new_name = utils.get_resource_name(name, prefix, suffix)
+
+        self.assertEqual(new_name, f'{prefix}{name}{suffix}')
+
+    def test_get_resource_name_with_prefix(self):
+        name = 'fun_name'
+        prefix = 'something/'
+
+        new_name = utils.get_resource_name(name, prefix)
+
+        self.assertEqual(new_name, f'{prefix}{name}')
+
+    def test_get_resource_name_with_sufix(self):
+        name = 'another'
+        suffix = '/something-else'
+
+        new_name = utils.get_resource_name(name, suffix=suffix)
+
+        self.assertEqual(new_name, f'{name}{suffix}')
+
+    def test_get_resource_name_non_ascii(self):
+        name = 'Ру́сский вое́нный кора́бль, иди́ на хуй!'
+        prefix = 'bar:'
+        suffix = ':baz'
+
+        new_name = utils.get_resource_name(name, prefix, suffix)
+
+        self.assertEqual(new_name, f'{prefix}{name}{suffix}')