Fix bug 680
[osm/N2VC.git] / n2vc / vnf.py
index 9f04405..a68e657 100644 (file)
@@ -19,7 +19,7 @@ if path not in sys.path:
 
 from juju.controller import Controller
 from juju.model import ModelObserver
-
+from juju.errors import JujuAPIError, JujuError
 
 # We might need this to connect to the websocket securely, but test and verify.
 try:
@@ -43,6 +43,10 @@ class N2VCPrimitiveExecutionFailed(Exception):
     """Something failed while attempting to execute a primitive."""
 
 
+class NetworkServiceDoesNotExist(Exception):
+    """The Network Service being acted against does not exist."""
+
+
 # Quiet the debug logging
 logging.getLogger('websockets.protocol').setLevel(logging.INFO)
 logging.getLogger('juju.client.connection').setLevel(logging.WARN)
@@ -53,13 +57,12 @@ logging.getLogger('juju.machine').setLevel(logging.WARN)
 class VCAMonitor(ModelObserver):
     """Monitor state changes within the Juju Model."""
     log = None
-    ns_name = None
-    applications = {}
 
     def __init__(self, ns_name):
         self.log = logging.getLogger(__name__)
 
         self.ns_name = ns_name
+        self.applications = {}
 
     def AddApplication(self, application_name, callback, *callback_args):
         if application_name not in self.applications:
@@ -144,22 +147,34 @@ class N2VC:
                  secret=None,
                  artifacts=None,
                  loop=None,
+                 juju_public_key=None,
+                 ca_cert=None,
                  ):
         """Initialize N2VC
-
-        :param vcaconfig dict A dictionary containing the VCA configuration
-
-        :param artifacts str The directory where charms required by a vnfd are
+        :param log obj: The logging object to log to
+        :param server str: The IP Address or Hostname of the Juju controller
+        :param port int: The port of the Juju Controller
+        :param user str: The Juju username to authenticate with
+        :param secret str: The Juju password to authenticate with
+        :param artifacts str: The directory where charms required by a vnfd are
             stored.
+        :param loop obj: The loop to use.
+        :param juju_public_key str: The contents of the Juju public SSH key
+        :param ca_cert str: The CA certificate to use to authenticate
+
 
         :Example:
-        n2vc = N2VC(vcaconfig={
-            'secret': 'MzI3MDJhOTYxYmM0YzRjNTJiYmY1Yzdm',
-            'user': 'admin',
-            'ip-address': '10.44.127.137',
-            'port': 17070,
-            'artifacts': '/path/to/charms'
-        })
+        client = n2vc.vnf.N2VC(
+            log=log,
+            server='10.1.1.28',
+            port=17070,
+            user='admin',
+            secret='admin',
+            artifacts='/app/storage/myvnf/charms',
+            loop=loop,
+            juju_public_key='<contents of the juju public key>',
+            ca_cert='<contents of CA certificate>',
+        )
         """
 
         # Initialize instance-level variables
@@ -176,7 +191,6 @@ class N2VC:
         }
 
         self.models = {}
-        self.default_model = None
 
         # Model Observers
         self.monitors = {}
@@ -187,6 +201,12 @@ class N2VC:
         self.username = ""
         self.secret = ""
 
+        self.juju_public_key = juju_public_key
+        if juju_public_key:
+            self._create_juju_public_key(juju_public_key)
+
+        self.ca_cert = ca_cert
+
         if log:
             self.log = log
         else:
@@ -219,6 +239,31 @@ class N2VC:
         """Close any open connections."""
         yield self.logout()
 
+    def _create_juju_public_key(self, public_key):
+        """Recreate the Juju public key on disk.
+
+        Certain libjuju commands expect to be run from the same machine as Juju
+         is bootstrapped to. This method will write the public key to disk in
+         that location: ~/.local/share/juju/ssh/juju_id_rsa.pub
+        """
+        # Make sure that we have a public key before writing to disk
+        if public_key is None or len(public_key) == 0:
+            if 'OSM_VCA_PUBKEY' in os.environ:
+                public_key = os.getenv('OSM_VCA_PUBKEY', '')
+                if len(public_key == 0):
+                    return
+            else:
+                return
+
+        path = "{}/.local/share/juju/ssh".format(
+            os.path.expanduser('~'),
+        )
+        if not os.path.exists(path):
+            os.makedirs(path)
+
+            with open('{}/juju_id_rsa.pub'.format(path), 'w') as f:
+                f.write(public_key)
+
     def notify_callback(self, model_name, application_name, status, message,
                         callback=None, *callback_args):
         try:
@@ -235,24 +280,99 @@ class N2VC:
         return True
 
     # Public methods
-    async def CreateNetworkService(self, nsd):
-        """Create a new model to encapsulate this network service.
+    async def Relate(self, model_name, vnfd):
+        """Create a relation between the charm-enabled VDUs in a VNF.
 
-        Create a new model in the Juju controller to encapsulate the
-        charms associated with a network service.
+        The Relation mapping has two parts: the id of the vdu owning the endpoint, and the name of the endpoint.
 
-        You can pass either the nsd record or the id of the network
-        service, but this method will fail without one of them.
+        vdu:
+            ...
+            relation:
+            -   provides: dataVM:db
+                requires: mgmtVM:app
+
+        This tells N2VC that the charm referred to by the dataVM vdu offers a relation named 'db', and the mgmtVM vdu has an 'app' endpoint that should be connected to a database.
+
+        :param str ns_name: The name of the network service.
+        :param dict vnfd: The parsed yaml VNF descriptor.
         """
-        if not self.authenticated:
-            await self.login()
 
-        # Ideally, we will create a unique model per network service.
-        # This change will require all components, i.e., LCM and SO, to use
-        # N2VC for 100% compatibility. If we adopt unique models for the LCM,
-        # services deployed via LCM would't be manageable via SO and vice versa
+        # Currently, the call to Relate() is made automatically after the
+        # deployment of each charm; if the relation depends on a charm that
+        # hasn't been deployed yet, the call will fail silently. This will
+        # prevent an API breakage, with the intent of making this an explicitly
+        # required call in a more object-oriented refactor of the N2VC API.
+
+        configs = []
+        vnf_config = vnfd.get("vnf-configuration")
+        if vnf_config:
+            juju = vnf_config['juju']
+            if juju:
+                configs.append(vnf_config)
+
+        for vdu in vnfd['vdu']:
+            vdu_config = vdu.get('vdu-configuration')
+            if vdu_config:
+                juju = vdu_config['juju']
+                if juju:
+                    configs.append(vdu_config)
+
+        def _get_application_name(name):
+            """Get the application name that's mapped to a vnf/vdu."""
+            vnf_member_index = 0
+            vnf_name = vnfd['name']
+
+            for vdu in vnfd.get('vdu'):
+                # Compare the named portion of the relation to the vdu's id
+                if vdu['id'] == name:
+                    application_name = self.FormatApplicationName(
+                        model_name,
+                        vnf_name,
+                        str(vnf_member_index),
+                    )
+                    return application_name
+                else:
+                    vnf_member_index += 1
+
+            return None
+
+        # Loop through relations
+        for cfg in configs:
+            if 'juju' in cfg:
+                if 'relation' in juju:
+                    for rel in juju['relation']:
+                        try:
+
+                            # get the application name for the provides
+                            (name, endpoint) = rel['provides'].split(':')
+                            application_name = _get_application_name(name)
+
+                            provides = "{}:{}".format(
+                                application_name,
+                                endpoint
+                            )
+
+                            # get the application name for thr requires
+                            (name, endpoint) = rel['requires'].split(':')
+                            application_name = _get_application_name(name)
+
+                            requires = "{}:{}".format(
+                                application_name,
+                                endpoint
+                            )
+                            self.log.debug("Relation: {} <-> {}".format(
+                                provides,
+                                requires
+                            ))
+                            await self.add_relation(
+                                model_name,
+                                provides,
+                                requires,
+                            )
+                        except Exception as e:
+                            self.log.debug("Exception: {}".format(e))
 
-        return self.default_model
+        return
 
     async def DeployCharms(self, model_name, application_name, vnfd,
                            charm_path, params={}, machine_spec={},
@@ -261,7 +381,7 @@ class N2VC:
 
         Deploy the charm(s) referenced in a VNF Descriptor.
 
-        :param str model_name: The name of the network service.
+        :param str model_name: The name or unique id of the network service.
         :param str application_name: The name of the application
         :param dict vnfd: The name of the application
         :param str charm_path: The path to the Juju charm
@@ -271,6 +391,8 @@ class N2VC:
             'rw_mgmt_ip': '1.2.3.4',
             # Pass the initial-config-primitives section of the vnf or vdu
             'initial-config-primitives': {...}
+            'user_values': dictionary with the day-1 parameters provided at instantiation time. It will replace values
+                inside < >. rw_mgmt_ip will be included here also
           }
         :param dict machine_spec: A dictionary describing the machine to
         install to
@@ -308,9 +430,6 @@ class N2VC:
         ##########################################
         # Get the model for this network service #
         ##########################################
-        # TODO: In a point release, we will use a model per deployed network
-        # service. In the meantime, we will always use the 'default' model.
-        model_name = 'default'
         model = await self.get_model(model_name)
 
         ########################################
@@ -324,34 +443,24 @@ class N2VC:
         # Register this application with the model-level event monitor #
         ################################################################
         if callback:
-            self.monitors[model_name].AddApplication(
+            self.log.debug("JujuApi: Registering callback for {}".format(
                 application_name,
-                callback,
-                *callback_args
-            )
+            ))
+            await self.Subscribe(model_name, application_name, callback, *callback_args)
 
         ########################################################
         # Check for specific machine placement (native charms) #
         ########################################################
         to = ""
         if machine_spec.keys():
-            if all(k in machine_spec for k in ['hostname', 'username']):
-                # Get the path to the previously generated ssh private key.
-                # Machines we're manually provisioned must have N2VC's public
-                # key injected, so if we don't have a keypair, raise an error.
-                private_key_path = ""
-
-                # Enlist the existing machine in Juju
-                machine = await self.model.add_machine(
-                    spec='ssh:{}@{}:{}'.format(
-                        specs['host'],
-                        specs['user'],
-                        private_key_path,
-                    )
-                )
-                # Set the machine id that the deploy below will use.
+            if all(k in machine_spec for k in ['host', 'user']):
+                # Enlist an existing machine as a Juju unit
+                machine = await model.add_machine(spec='ssh:{}@{}:{}'.format(
+                    machine_spec['user'],
+                    machine_spec['host'],
+                    self.GetPrivateKeyPath(),
+                ))
                 to = machine.id
-            pass
 
         #######################################
         # Get the initial charm configuration #
@@ -369,7 +478,8 @@ class N2VC:
             {'<rw_mgmt_ip>': rw_mgmt_ip}
         )
 
-        self.log.debug("JujuApi: Deploying charm ({}) from {}".format(
+        self.log.debug("JujuApi: Deploying charm ({}/{}) from {}".format(
+            model_name,
             application_name,
             charm_path,
             to=to,
@@ -393,14 +503,19 @@ class N2VC:
             to=to,
         )
 
+        # Map the vdu id<->app name,
+        #
+        await self.Relate(model_name, vnfd)
+
         # #######################################
         # # Execute initial config primitive(s) #
         # #######################################
-        await self.ExecuteInitialPrimitives(
+        uuids = await self.ExecuteInitialPrimitives(
             model_name,
             application_name,
             params,
         )
+        return uuids
 
         # primitives = {}
         #
@@ -453,9 +568,6 @@ class N2VC:
             if not self.authenticated:
                 await self.login()
 
-            # FIXME: This is hard-coded until model-per-ns is added
-            model_name = 'default'
-
             model = await self.get_model(model_name)
 
             results = await model.get_action_status(uuid)
@@ -481,9 +593,6 @@ class N2VC:
             if not self.authenticated:
                 await self.login()
 
-            # FIXME: This is hard-coded until model-per-ns is added
-            model_name = 'default'
-
             model = await self.get_model(model_name)
             results = await model.get_action_output(uuid, 60)
         except Exception as e:
@@ -585,15 +694,20 @@ class N2VC:
                 else:
                     seq = primitive['seq']
 
-                    params = {}
+                    params_ = {}
                     if 'parameter' in primitive:
-                        params = primitive['parameter']
+                        params_ = primitive['parameter']
+
+                    user_values = params.get("user_values", {})
+                    if 'rw_mgmt_ip' not in user_values:
+                        user_values['rw_mgmt_ip'] = None
+                        # just for backward compatibility, because it will be provided always by modern version of LCM
 
                     primitives[seq] = {
                         'name': primitive['name'],
                         'parameters': self._map_primitive_parameters(
-                            params,
-                            {'<rw_mgmt_ip>': None}
+                            params_,
+                            user_values
                         ),
                     }
 
@@ -621,7 +735,7 @@ class N2VC:
 
         Execute a primitive defined in the VNF descriptor.
 
-        :param str model_name: The name of the network service.
+        :param str model_name: The name or unique id of the network service.
         :param str application_name: The name of the application
         :param str primitive: The name of the primitive to execute.
         :param obj callback: A callback function to receive status changes.
@@ -636,15 +750,12 @@ class N2VC:
             'initial-config-primitives': {...}
           }
         """
-        self.log.debug("Executing {}".format(primitive))
+        self.log.debug("Executing primitive={} params={}".format(primitive, params))
         uuid = None
         try:
             if not self.authenticated:
                 await self.login()
 
-            # FIXME: This is hard-coded until model-per-ns is added
-            model_name = 'default'
-
             model = await self.get_model(model_name)
 
             if primitive == 'config':
@@ -689,7 +800,7 @@ class N2VC:
             app = await self.get_application(model, application_name)
             if app:
                 # Remove this application from event monitoring
-                self.monitors[model_name].RemoveApplication(application_name)
+                await self.Unsubscribe(model_name, application_name)
 
                 # self.notify_callback(model_name, application_name, "removing", callback, *callback_args)
                 self.log.debug(
@@ -697,11 +808,13 @@ class N2VC:
                 )
                 await app.remove()
 
-                # Notify the callback that this charm has been removed.
+                await self.disconnect_model(self.monitors[model_name])
+
                 self.notify_callback(
                     model_name,
                     application_name,
                     "removed",
+                    "Removing charm {}".format(application_name),
                     callback,
                     *callback_args,
                 )
@@ -711,13 +824,70 @@ class N2VC:
             self.log.debug(e)
             raise e
 
-    async def DestroyNetworkService(self, nsd):
-        raise NotImplementedError()
+    async def CreateNetworkService(self, ns_uuid):
+        """Create a new Juju model for the Network Service.
+
+        Creates a new Model in the Juju Controller.
+
+        :param str ns_uuid: A unique id representing an instaance of a
+            Network Service.
+
+        :returns: True if the model was created. Raises JujuError on failure.
+        """
+        if not self.authenticated:
+            await self.login()
+
+        models = await self.controller.list_models()
+        if ns_uuid not in models:
+            try:
+                self.models[ns_uuid] = await self.controller.add_model(
+                    ns_uuid
+                )
+            except JujuError as e:
+                if "already exists" not in e.message:
+                    raise e
+
+            # Create an observer for this model
+            await self.create_model_monitor(ns_uuid)
+
+        return True
+
+    async def DestroyNetworkService(self, ns_uuid):
+        """Destroy a Network Service.
+
+        Destroy the Network Service and any deployed charms.
+
+        :param ns_uuid The unique id of the Network Service
+
+        :returns: True if the model was created. Raises JujuError on failure.
+        """
+
+        # Do not delete the default model. The default model was used by all
+        # Network Services, prior to the implementation of a model per NS.
+        if ns_uuid.lower() == "default":
+            return False
+
+        if not self.authenticated:
+            self.log.debug("Authenticating with Juju")
+            await self.login()
+
+        # Disconnect from the Model
+        if ns_uuid in self.models:
+            await self.disconnect_model(self.models[ns_uuid])
+
+        try:
+            await self.controller.destroy_models(ns_uuid)
+        except JujuError:
+            raise NetworkServiceDoesNotExist(
+                "The Network Service '{}' does not exist".format(ns_uuid)
+            )
+
+        return True
 
     async def GetMetrics(self, model_name, application_name):
         """Get the metrics collected by the VCA.
 
-        :param model_name The name of the model
+        :param model_name The name or unique id of the network service
         :param application_name The name of the application
         """
         metrics = {}
@@ -735,24 +905,59 @@ class N2VC:
             return True
         return False
 
+    async def Subscribe(self, ns_name, application_name, callback, *callback_args):
+        """Subscribe to callbacks for an application.
+
+        :param ns_name str: The name of the Network Service
+        :param application_name str: The name of the application
+        :param callback obj: The callback method
+        :param callback_args list: The list of arguments to append to calls to
+            the callback method
+        """
+        self.monitors[ns_name].AddApplication(
+            application_name,
+            callback,
+            *callback_args
+        )
+
+    async def Unsubscribe(self, ns_name, application_name):
+        """Unsubscribe to callbacks for an application.
+
+        Unsubscribes the caller from notifications from a deployed application.
+
+        :param ns_name str: The name of the Network Service
+        :param application_name str: The name of the application
+        """
+        self.monitors[ns_name].RemoveApplication(
+            application_name,
+        )
+
     # Non-public methods
-    async def add_relation(self, a, b, via=None):
+    async def add_relation(self, model_name, relation1, relation2):
         """
         Add a relation between two application endpoints.
 
-        :param a An application endpoint
-        :param b An application endpoint
-        :param via The egress subnet(s) for outbound traffic, e.g.,
-            (192.168.0.0/16,10.0.0.0/8)
+        :param str model_name: The name or unique id of the network service
+        :param str relation1: '<application>[:<relation_name>]'
+        :param str relation2: '<application>[:<relation_name>]'
         """
+
         if not self.authenticated:
             await self.login()
 
-        m = await self.get_model()
+        m = await self.get_model(model_name)
         try:
-            m.add_relation(a, b, via)
-        finally:
-            await m.disconnect()
+            await m.add_relation(relation1, relation2)
+        except JujuAPIError as e:
+            # If one of the applications in the relationship doesn't exist,
+            # or the relation has already been added, let the operation fail
+            # silently.
+            if 'not found' in e.message:
+                return
+            if 'already exists' in e.message:
+                return
+
+            raise e
 
     # async def apply_config(self, config, application):
     #     """Apply a configuration to the application."""
@@ -783,27 +988,45 @@ class N2VC:
 
         return config
 
-    def _map_primitive_parameters(self, parameters, values):
+    def _map_primitive_parameters(self, parameters, user_values):
         params = {}
         for parameter in parameters:
             param = str(parameter['name'])
+            value = parameter.get('value')
+
+            # map parameters inside a < >; e.g. <rw_mgmt_ip>. with the provided user_values.
+            # Must exist at user_values except if there is a default value
+            if isinstance(value, str) and value.startswith("<") and value.endswith(">"):
+                if parameter['value'][1:-1] in user_values:
+                    value = user_values[parameter['value'][1:-1]]
+                elif 'default-value' in parameter:
+                    value = parameter['default-value']
+                else:
+                    raise KeyError("parameter {}='{}' not supplied ".format(param, value))
+
+            # If there's no value, use the default-value (if set)
+            if value is None and 'default-value' in parameter:
+                value = parameter['default-value']
 
             # Typecast parameter value, if present
-            if 'data-type' in parameter:
-                paramtype = str(parameter['data-type']).lower()
-                value = None
-
-                if paramtype == "integer":
-                    value = int(parameter['value'])
-                elif paramtype == "boolean":
-                    value = bool(parameter['value'])
+            paramtype = "string"
+            try:
+                if 'data-type' in parameter:
+                    paramtype = str(parameter['data-type']).lower()
+
+                    if paramtype == "integer":
+                        value = int(value)
+                    elif paramtype == "boolean":
+                        value = bool(value)
+                    else:
+                        value = str(value)
                 else:
-                    value = str(parameter['value'])
+                    # If there's no data-type, assume the value is a string
+                    value = str(value)
+            except ValueError:
+                raise ValueError("parameter {}='{}' cannot be converted to type {}".format(param, value, paramtype))
 
-            if parameter['value'] == "<rw_mgmt_ip>":
-                params[param] = str(values[parameter['value']])
-            else:
-                params[param] = value
+            params[param] = value
         return params
 
     def _get_config_from_yang(self, config_primitive, values):
@@ -820,7 +1043,6 @@ class N2VC:
 
         return config
 
-    @staticmethod
     def FormatApplicationName(self, *args):
         """
         Generate a Juju-compatible Application name
@@ -836,7 +1058,6 @@ class N2VC:
 
             FormatApplicationName("ping_pong_ns", "ping_vnf", "a")
         """
-
         appname = ""
         for c in "-".join(list(args)):
             if c.isdigit():
@@ -844,7 +1065,7 @@ class N2VC:
             elif not c.isalpha():
                 c = "-"
             appname += c
-        return re.sub('\-+', '-', appname.lower())
+        return re.sub('-+', '-', appname.lower())
 
     # def format_application_name(self, nsd_name, vnfr_name, member_vnf_index=0):
     #     """Format the name of the application
@@ -884,7 +1105,7 @@ class N2VC:
 
         return app
 
-    async def get_model(self, model_name='default'):
+    async def get_model(self, model_name):
         """Get a model from the Juju Controller.
 
         Note: Model objects returned must call disconnected() before it goes
@@ -893,16 +1114,39 @@ class N2VC:
             await self.login()
 
         if model_name not in self.models:
-            self.models[model_name] = await self.controller.get_model(
-                model_name,
-            )
+            # Get the models in the controller
+            models = await self.controller.list_models()
+
+            if model_name not in models:
+                try:
+                    self.models[model_name] = await self.controller.add_model(
+                        model_name
+                    )
+                except JujuError as e:
+                    if "already exists" not in e.message:
+                        raise e
+            else:
+                self.models[model_name] = await self.controller.get_model(
+                    model_name
+                )
+
             self.refcount['model'] += 1
 
             # Create an observer for this model
+            await self.create_model_monitor(model_name)
+
+        return self.models[model_name]
+
+    async def create_model_monitor(self, model_name):
+        """Create a monitor for the model, if none exists."""
+        if not self.authenticated:
+            await self.login()
+
+        if model_name not in self.monitors:
             self.monitors[model_name] = VCAMonitor(model_name)
             self.models[model_name].add_observer(self.monitors[model_name])
 
-        return self.models[model_name]
+        return True
 
     async def login(self):
         """Login to the Juju controller."""
@@ -914,7 +1158,6 @@ class N2VC:
 
         self.log.debug("JujuApi: Logging into controller")
 
-        cacert = None
         self.controller = Controller(loop=self.loop)
 
         if self.secret:
@@ -930,7 +1173,7 @@ class N2VC:
                 endpoint=self.endpoint,
                 username=self.user,
                 password=self.secret,
-                cacert=cacert,
+                cacert=self.ca_cert,
             )
             self.refcount['controller'] += 1
         else:
@@ -950,21 +1193,11 @@ class N2VC:
     async def logout(self):
         """Logout of the Juju controller."""
         if not self.authenticated:
-            return
+            return False
 
         try:
-            if self.default_model:
-                self.log.debug("Disconnecting model {}".format(
-                    self.default_model
-                ))
-                await self.default_model.disconnect()
-                self.refcount['model'] -= 1
-                self.default_model = None
-
             for model in self.models:
-                await self.models[model].disconnect()
-                self.refcount['model'] -= 1
-                self.models[model] = None
+                await self.disconnect_model(model)
 
             if self.controller:
                 self.log.debug("Disconnecting controller {}".format(
@@ -983,6 +1216,15 @@ class N2VC:
                 "Fatal error logging out of Juju Controller: {}".format(e)
             )
             raise e
+        return True
+
+    async def disconnect_model(self, model):
+        self.log.debug("Disconnecting model {}".format(model))
+        if model in self.models:
+            print("Disconnecting model")
+            await self.models[model].disconnect()
+            self.refcount['model'] -= 1
+            self.models[model] = None
 
     # async def remove_application(self, name):
     #     """Remove the application."""
@@ -1013,12 +1255,14 @@ class N2VC:
         finally:
             await m.disconnect()
 
-    async def resolve_error(self, application=None):
+    async def resolve_error(self, model_name, application=None):
         """Resolve units in error state."""
         if not self.authenticated:
             await self.login()
 
-        app = await self.get_application(self.default_model, application)
+        model = await self.get_model(model_name)
+
+        app = await self.get_application(model, application)
         if app:
             self.log.debug(
                 "JujuApi: Resolving errors for application {}".format(
@@ -1029,7 +1273,7 @@ class N2VC:
             for unit in app.units:
                 app.resolved(retry=True)
 
-    async def run_action(self, application, action_name, **params):
+    async def run_action(self, model_name, application, action_name, **params):
         """Execute an action and return an Action object."""
         if not self.authenticated:
             await self.login()
@@ -1040,7 +1284,10 @@ class N2VC:
                 'results': None,
             }
         }
-        app = await self.get_application(self.default_model, application)
+
+        model = await self.get_model(model_name)
+
+        app = await self.get_application(model, application)
         if app:
             # We currently only have one unit per application
             # so use the first unit available.
@@ -1103,14 +1350,10 @@ class N2VC:
         if not self.authenticated:
             await self.login()
 
-        # TODO: In a point release, we will use a model per deployed network
-        # service. In the meantime, we will always use the 'default' model.
-        model_name = 'default'
         model = await self.get_model(model_name)
 
         app = await self.get_application(model, application_name)
         self.log.debug("Application: {}".format(app))
-        # app = await self.get_application(model_name, application_name)
         if app:
             self.log.debug(
                 "JujuApi: Waiting {} seconds for Application {}".format(