Make network resource creation in isolation configurable

This commit adds a helper method to the base test class
set_network_resources(). This method should be called before the super
call in setUpClass and lets you specify which network resources
are created for a test class in tenant isolation. This is useful for
fine tuning each test class so that only the resources that are needed
get created.

Change-Id: I8f66534dbe3f48552ed6cd238ad237c46d7ee60c
diff --git a/tempest/api/image/base.py b/tempest/api/image/base.py
index 28ed5b6..91f725e 100644
--- a/tempest/api/image/base.py
+++ b/tempest/api/image/base.py
@@ -34,7 +34,8 @@
         super(BaseImageTest, cls).setUpClass()
         cls.created_images = []
         cls._interface = 'json'
-        cls.isolated_creds = isolated_creds.IsolatedCreds(cls.__name__)
+        cls.isolated_creds = isolated_creds.IsolatedCreds(
+            cls.__name__, network_resources=cls.network_resources)
         if not cls.config.service_available.glance:
             skip_msg = ("%s skipped as glance is not available" % cls.__name__)
             raise cls.skipException(skip_msg)
diff --git a/tempest/api/object_storage/base.py b/tempest/api/object_storage/base.py
index 47d8cca..b4928dd 100644
--- a/tempest/api/object_storage/base.py
+++ b/tempest/api/object_storage/base.py
@@ -32,7 +32,8 @@
         if not cls.config.service_available.swift:
             skip_msg = ("%s skipped as swift is not available" % cls.__name__)
             raise cls.skipException(skip_msg)
-        cls.isolated_creds = isolated_creds.IsolatedCreds(cls.__name__)
+        cls.isolated_creds = isolated_creds.IsolatedCreds(
+            cls.__name__, network_resources=cls.network_resources)
         if cls.config.compute.allow_tenant_isolation:
             # Get isolated creds for normal user
             creds = cls.isolated_creds.get_primary_creds()
diff --git a/tempest/common/isolated_creds.py b/tempest/common/isolated_creds.py
index da60318..9c0d7f6 100644
--- a/tempest/common/isolated_creds.py
+++ b/tempest/common/isolated_creds.py
@@ -32,7 +32,8 @@
 class IsolatedCreds(object):
 
     def __init__(self, name, tempest_client=True, interface='json',
-                 password='pass'):
+                 password='pass', network_resources=None):
+        self.network_resources = network_resources
         self.isolated_creds = {}
         self.isolated_net_resources = {}
         self.ports = []
@@ -198,15 +199,33 @@
         network = None
         subnet = None
         router = None
+        # Make sure settings
+        if self.network_resources:
+            if self.network_resources['router']:
+                if (not self.network_resources['subnet'] or
+                    not self.network_resources['network']):
+                    raise exceptions.InvalidConfiguration(
+                        'A router requires a subnet and network')
+            elif self.network_resources['subnet']:
+                if not self.network_resources['network']:
+                    raise exceptions.InvalidConfiguration(
+                        'A subnet requires a network')
+            elif self.network_resources['dhcp']:
+                raise exceptions.InvalidConfiguration('DHCP requires a subnet')
+
         data_utils.rand_name_root = data_utils.rand_name(self.name)
-        network_name = data_utils.rand_name_root + "-network"
-        network = self._create_network(network_name, tenant_id)
+        if not self.network_resources or self.network_resources['network']:
+            network_name = data_utils.rand_name_root + "-network"
+            network = self._create_network(network_name, tenant_id)
         try:
-            subnet_name = data_utils.rand_name_root + "-subnet"
-            subnet = self._create_subnet(subnet_name, tenant_id, network['id'])
-            router_name = data_utils.rand_name_root + "-router"
-            router = self._create_router(router_name, tenant_id)
-            self._add_router_interface(router['id'], subnet['id'])
+            if not self.network_resources or self.network_resources['subnet']:
+                subnet_name = data_utils.rand_name_root + "-subnet"
+                subnet = self._create_subnet(subnet_name, tenant_id,
+                                             network['id'])
+            if not self.network_resources or self.network_resources['router']:
+                router_name = data_utils.rand_name_root + "-router"
+                router = self._create_router(router_name, tenant_id)
+                self._add_router_interface(router['id'], subnet['id'])
         except Exception:
             if router:
                 self._clear_isolated_router(router['id'], router['name'])
@@ -230,14 +249,25 @@
         if not self.tempest_client:
             body = {'subnet': {'name': subnet_name, 'tenant_id': tenant_id,
                                'network_id': network_id, 'ip_version': 4}}
+            if self.network_resources:
+                body['enable_dhcp'] = self.network_resources['dhcp']
         base_cidr = netaddr.IPNetwork(CONF.network.tenant_network_cidr)
         mask_bits = CONF.network.tenant_network_mask_bits
         for subnet_cidr in base_cidr.subnet(mask_bits):
             try:
                 if self.tempest_client:
-                    resp, resp_body = self.network_admin_client.create_subnet(
-                        network_id, str(subnet_cidr), name=subnet_name,
-                        tenant_id=tenant_id)
+                    if self.network_resources:
+                        resp, resp_body = self.network_admin_client.\
+                            create_subnet(
+                                network_id, str(subnet_cidr),
+                                name=subnet_name,
+                                tenant_id=tenant_id,
+                                enable_dhcp=self.network_resources['dhcp'])
+                    else:
+                        resp, resp_body = self.network_admin_client.\
+                            create_subnet(network_id, str(subnet_cidr),
+                                          name=subnet_name,
+                                          tenant_id=tenant_id)
                 else:
                     body['subnet']['cidr'] = str(subnet_cidr)
                     resp_body = self.network_admin_client.create_subnet(body)
@@ -431,26 +461,27 @@
         net_client = self.network_admin_client
         for cred in self.isolated_net_resources:
             network, subnet, router = self.isolated_net_resources.get(cred)
-            try:
-                if self.tempest_client:
-                    net_client.remove_router_interface_with_subnet_id(
-                        router['id'], subnet['id'])
-                else:
-                    body = {'subnet_id': subnet['id']}
-                    net_client.remove_interface_router(router['id'], body)
-            except exceptions.NotFound:
-                LOG.warn('router with name: %s not found for delete' %
-                         router['name'])
-                pass
-            self._clear_isolated_router(router['id'], router['name'])
-            # TODO(mlavalle) This method call will be removed once patch
-            # https://review.openstack.org/#/c/46563/ merges in Neutron
-            self._cleanup_ports(network['id'])
-            self._clear_isolated_subnet(subnet['id'], subnet['name'])
-            self._clear_isolated_network(network['id'], network['name'])
-            LOG.info("Cleared isolated network resources: \n"
-                     + " network: %s, subnet: %s, router: %s"
-                     % (network['name'], subnet['name'], router['name']))
+            if self.network_resources.get('router'):
+                try:
+                    if self.tempest_client:
+                        net_client.remove_router_interface_with_subnet_id(
+                            router['id'], subnet['id'])
+                    else:
+                        body = {'subnet_id': subnet['id']}
+                        net_client.remove_interface_router(router['id'], body)
+                except exceptions.NotFound:
+                    LOG.warn('router with name: %s not found for delete' %
+                             router['name'])
+                    pass
+                self._clear_isolated_router(router['id'], router['name'])
+            if self.network_resources.get('network'):
+                # TODO(mlavalle) This method call will be removed once patch
+                # https://review.openstack.org/#/c/46563/ merges in Neutron
+                self._cleanup_ports(network['id'])
+            if self.network_resources.get('subnet'):
+                self._clear_isolated_subnet(subnet['id'], subnet['name'])
+            if self.network_resources.get('network'):
+                self._clear_isolated_network(network['id'], network['name'])
 
     def clear_isolated_creds(self):
         if not self.isolated_creds:
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index 409fcc2..2b5a770 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -235,7 +235,8 @@
     def setUpClass(cls):
         super(OfficialClientTest, cls).setUpClass()
         cls.isolated_creds = isolated_creds.IsolatedCreds(
-            __name__, tempest_client=False)
+            __name__, tempest_client=False,
+            network_resources=cls.network_resources)
 
         username, password, tenant_name = cls.credentials()
 
diff --git a/tempest/test.py b/tempest/test.py
index d57ed83..83a4319 100644
--- a/tempest/test.py
+++ b/tempest/test.py
@@ -230,6 +230,8 @@
 
     setUpClassCalled = False
 
+    network_resources = {}
+
     @classmethod
     def setUpClass(cls):
         if hasattr(super(BaseTestCase, cls), 'setUpClass'):
@@ -277,7 +279,8 @@
         """
         Returns an Openstack client manager
         """
-        cls.isolated_creds = isolated_creds.IsolatedCreds(cls.__name__)
+        cls.isolated_creds = isolated_creds.IsolatedCreds(
+            cls.__name__, network_resources=cls.network_resources)
 
         force_tenant_isolation = getattr(cls, 'force_tenant_isolation', None)
         if (cls.config.compute.allow_tenant_isolation or
@@ -319,6 +322,23 @@
             cls.config.identity.uri
         )
 
+    @classmethod
+    def set_network_resources(self, network=False, router=False, subnet=False,
+                              dhcp=False):
+        """Specify which network resources should be created
+
+        @param network
+        @param router
+        @param subnet
+        @param dhcp
+        """
+        self.network_resources = {
+            'network': network,
+            'router': router,
+            'subnet': subnet,
+            'dhcp': dhcp,
+        }
+
 
 def call_until_true(func, duration, sleep_for):
     """