n2vc/vnf.py

   1 import asyncio
   2 import logging
   3 import os
   4 import os.path
   5 import re
   6 import shlex
   7 import ssl
   8 import subprocess
   9 import sys
  10 # import time
  11
  12 # FIXME: this should load the juju inside or modules without having to
  13 # explicitly install it. Check why it's not working.
  14 # Load our subtree of the juju library
  15 path = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
  16 path = os.path.join(path, "modules/libjuju/")
  17 if path not in sys.path:
  18     sys.path.insert(1, path)
  19
  20 from juju.controller import Controller
  21 from juju.model import ModelObserver
  22 from juju.errors import JujuAPIError
  23
  24 # We might need this to connect to the websocket securely, but test and verify.
  25 try:
  26     ssl._create_default_https_context = ssl._create_unverified_context
  27 except AttributeError:
  28     # Legacy Python doesn't verify by default (see pep-0476)
  29     #   https://www.python.org/dev/peps/pep-0476/
  30     pass
  31
  32
  33 # Custom exceptions
  34 class JujuCharmNotFound(Exception):
  35     """The Charm can't be found or is not readable."""
  36
  37
  38 class JujuApplicationExists(Exception):
  39     """The Application already exists."""
  40
  41
  42 class N2VCPrimitiveExecutionFailed(Exception):
  43     """Something failed while attempting to execute a primitive."""
  44
  45
  46 # Quiet the debug logging
  47 logging.getLogger('websockets.protocol').setLevel(logging.INFO)
  48 logging.getLogger('juju.client.connection').setLevel(logging.WARN)
  49 logging.getLogger('juju.model').setLevel(logging.WARN)
  50 logging.getLogger('juju.machine').setLevel(logging.WARN)
  51
  52
  53 class VCAMonitor(ModelObserver):
  54     """Monitor state changes within the Juju Model."""
  55     log = None
  56     ns_name = None
  57     applications = {}
  58
  59     def __init__(self, ns_name):
  60         self.log = logging.getLogger(__name__)
  61
  62         self.ns_name = ns_name
  63
  64     def AddApplication(self, application_name, callback, *callback_args):
  65         if application_name not in self.applications:
  66             self.applications[application_name] = {
  67                 'callback': callback,
  68                 'callback_args': callback_args
  69             }
  70
  71     def RemoveApplication(self, application_name):
  72         if application_name in self.applications:
  73             del self.applications[application_name]
  74
  75     async def on_change(self, delta, old, new, model):
  76         """React to changes in the Juju model."""
  77
  78         if delta.entity == "unit":
  79             # Ignore change events from other applications
  80             if delta.data['application'] not in self.applications.keys():
  81                 return
  82
  83             try:
  84
  85                 application_name = delta.data['application']
  86
  87                 callback = self.applications[application_name]['callback']
  88                 callback_args = \
  89                     self.applications[application_name]['callback_args']
  90
  91                 if old and new:
  92                     # Fire off a callback with the application state
  93                     if callback:
  94                         callback(
  95                             self.ns_name,
  96                             delta.data['application'],
  97                             new.workload_status,
  98                             new.workload_status_message,
  99                             *callback_args)
 100
 101                 if old and not new:
 102                     # This is a charm being removed
 103                     if callback:
 104                         callback(
 105                             self.ns_name,
 106                             delta.data['application'],
 107                             "removed",
 108                             "",
 109                             *callback_args)
 110             except Exception as e:
 111                 self.log.debug("[1] notify_callback exception: {}".format(e))
 112
 113         elif delta.entity == "action":
 114             # TODO: Decide how we want to notify the user of actions
 115
 116             # uuid = delta.data['id']     # The Action's unique id
 117             # msg = delta.data['message'] # The output of the action
 118             #
 119             # if delta.data['status'] == "pending":
 120             #     # The action is queued
 121             #     pass
 122             # elif delta.data['status'] == "completed""
 123             #     # The action was successful
 124             #     pass
 125             # elif delta.data['status'] == "failed":
 126             #     # The action failed.
 127             #     pass
 128
 129             pass
 130
 131 ########
 132 # TODO
 133 #
 134 # Create unique models per network service
 135 # Document all public functions
 136
 137
 138 class N2VC:
 139     def __init__(self,
 140                  log=None,
 141                  server='127.0.0.1',
 142                  port=17070,
 143                  user='admin',
 144                  secret=None,
 145                  artifacts=None,
 146                  loop=None,
 147                  ):
 148         """Initialize N2VC
 149
 150         :param vcaconfig dict A dictionary containing the VCA configuration
 151
 152         :param artifacts str The directory where charms required by a vnfd are
 153             stored.
 154
 155         :Example:
 156         n2vc = N2VC(vcaconfig={
 157             'secret': 'MzI3MDJhOTYxYmM0YzRjNTJiYmY1Yzdm',
 158             'user': 'admin',
 159             'ip-address': '10.44.127.137',
 160             'port': 17070,
 161             'artifacts': '/path/to/charms'
 162         })
 163         """
 164
 165         # Initialize instance-level variables
 166         self.api = None
 167         self.log = None
 168         self.controller = None
 169         self.connecting = False
 170         self.authenticated = False
 171
 172         # For debugging
 173         self.refcount = {
 174             'controller': 0,
 175             'model': 0,
 176         }
 177
 178         self.models = {}
 179         self.default_model = None
 180
 181         # Model Observers
 182         self.monitors = {}
 183
 184         # VCA config
 185         self.hostname = ""
 186         self.port = 17070
 187         self.username = ""
 188         self.secret = ""
 189
 190         if log:
 191             self.log = log
 192         else:
 193             self.log = logging.getLogger(__name__)
 194
 195         # Quiet websocket traffic
 196         logging.getLogger('websockets.protocol').setLevel(logging.INFO)
 197         logging.getLogger('juju.client.connection').setLevel(logging.WARN)
 198         logging.getLogger('model').setLevel(logging.WARN)
 199         # logging.getLogger('websockets.protocol').setLevel(logging.DEBUG)
 200
 201         self.log.debug('JujuApi: instantiated')
 202
 203         self.server = server
 204         self.port = port
 205
 206         self.secret = secret
 207         if user.startswith('user-'):
 208             self.user = user
 209         else:
 210             self.user = 'user-{}'.format(user)
 211
 212         self.endpoint = '%s:%d' % (server, int(port))
 213
 214         self.artifacts = artifacts
 215
 216         self.loop = loop or asyncio.get_event_loop()
 217
 218     def __del__(self):
 219         """Close any open connections."""
 220         yield self.logout()
 221
 222     def notify_callback(self, model_name, application_name, status, message,
 223                         callback=None, *callback_args):
 224         try:
 225             if callback:
 226                 callback(
 227                     model_name,
 228                     application_name,
 229                     status, message,
 230                     *callback_args,
 231                 )
 232         except Exception as e:
 233             self.log.error("[0] notify_callback exception {}".format(e))
 234             raise e
 235         return True
 236
 237     # Public methods
 238     async def CreateNetworkService(self, nsd):
 239         """Create a new model to encapsulate this network service.
 240
 241         Create a new model in the Juju controller to encapsulate the
 242         charms associated with a network service.
 243
 244         You can pass either the nsd record or the id of the network
 245         service, but this method will fail without one of them.
 246         """
 247         if not self.authenticated:
 248             await self.login()
 249
 250         # Ideally, we will create a unique model per network service.
 251         # This change will require all components, i.e., LCM and SO, to use
 252         # N2VC for 100% compatibility. If we adopt unique models for the LCM,
 253         # services deployed via LCM would't be manageable via SO and vice versa
 254
 255         return self.default_model
 256
 257     async def Relate(self, ns_name, vnfd):
 258         """Create a relation between the charm-enabled VDUs in a VNF.
 259
 260         The Relation mapping has two parts: the id of the vdu owning the endpoint, and the name of the endpoint.
 261
 262         vdu:
 263             ...
 264             relation:
 265             -   provides: dataVM:db
 266                 requires: mgmtVM:app
 267
 268         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.
 269
 270         :param str ns_name: The name of the network service.
 271         :param dict vnfd: The parsed yaml VNF descriptor.
 272         """
 273
 274         # Currently, the call to Relate() is made automatically after the
 275         # deployment of each charm; if the relation depends on a charm that
 276         # hasn't been deployed yet, the call will fail silently. This will
 277         # prevent an API breakage, with the intent of making this an explicitly
 278         # required call in a more object-oriented refactor of the N2VC API.
 279
 280         configs = []
 281         vnf_config = vnfd.get("vnf-configuration")
 282         if vnf_config:
 283             juju = vnf_config['juju']
 284             if juju:
 285                 configs.append(vnf_config)
 286
 287         for vdu in vnfd['vdu']:
 288             vdu_config = vdu.get('vdu-configuration')
 289             if vdu_config:
 290                 juju = vdu_config['juju']
 291                 if juju:
 292                     configs.append(vdu_config)
 293
 294         def _get_application_name(name):
 295             """Get the application name that's mapped to a vnf/vdu."""
 296             vnf_member_index = 0
 297             vnf_name = vnfd['name']
 298
 299             for vdu in vnfd.get('vdu'):
 300                 # Compare the named portion of the relation to the vdu's id
 301                 if vdu['id'] == name:
 302                     application_name = self.FormatApplicationName(
 303                         ns_name,
 304                         vnf_name,
 305                         str(vnf_member_index),
 306                     )
 307                     return application_name
 308                 else:
 309                     vnf_member_index += 1
 310
 311             return None
 312
 313         # Loop through relations
 314         for cfg in configs:
 315             if 'juju' in cfg:
 316                 if 'relation' in juju:
 317                     for rel in juju['relation']:
 318                         try:
 319
 320                             # get the application name for the provides
 321                             (name, endpoint) = rel['provides'].split(':')
 322                             application_name = _get_application_name(name)
 323
 324                             provides = "{}:{}".format(
 325                                 application_name,
 326                                 endpoint
 327                             )
 328
 329                             # get the application name for thr requires
 330                             (name, endpoint) = rel['requires'].split(':')
 331                             application_name = _get_application_name(name)
 332
 333                             requires = "{}:{}".format(
 334                                 application_name,
 335                                 endpoint
 336                             )
 337                             self.log.debug("Relation: {} <-> {}".format(
 338                                 provides,
 339                                 requires
 340                             ))
 341                             await self.add_relation(
 342                                 ns_name,
 343                                 provides,
 344                                 requires,
 345                             )
 346                         except Exception as e:
 347                             self.log.debug("Exception: {}".format(e))
 348
 349         return
 350
 351     async def DeployCharms(self, model_name, application_name, vnfd,
 352                            charm_path, params={}, machine_spec={},
 353                            callback=None, *callback_args):
 354         """Deploy one or more charms associated with a VNF.
 355
 356         Deploy the charm(s) referenced in a VNF Descriptor.
 357
 358         :param str model_name: The name of the network service.
 359         :param str application_name: The name of the application
 360         :param dict vnfd: The name of the application
 361         :param str charm_path: The path to the Juju charm
 362         :param dict params: A dictionary of runtime parameters
 363           Examples::
 364           {
 365             'rw_mgmt_ip': '1.2.3.4',
 366             # Pass the initial-config-primitives section of the vnf or vdu
 367             'initial-config-primitives': {...}
 368           }
 369         :param dict machine_spec: A dictionary describing the machine to
 370         install to
 371           Examples::
 372           {
 373             'hostname': '1.2.3.4',
 374             'username': 'ubuntu',
 375           }
 376         :param obj callback: A callback function to receive status changes.
 377         :param tuple callback_args: A list of arguments to be passed to the
 378         callback
 379         """
 380
 381         ########################################################
 382         # Verify the path to the charm exists and is readable. #
 383         ########################################################
 384         if not os.path.exists(charm_path):
 385             self.log.debug("Charm path doesn't exist: {}".format(charm_path))
 386             self.notify_callback(
 387                 model_name,
 388                 application_name,
 389                 "failed",
 390                 callback,
 391                 *callback_args,
 392             )
 393             raise JujuCharmNotFound("No artifacts configured.")
 394
 395         ################################
 396         # Login to the Juju controller #
 397         ################################
 398         if not self.authenticated:
 399             self.log.debug("Authenticating with Juju")
 400             await self.login()
 401
 402         ##########################################
 403         # Get the model for this network service #
 404         ##########################################
 405         # TODO: In a point release, we will use a model per deployed network
 406         # service. In the meantime, we will always use the 'default' model.
 407         model_name = 'default'
 408         model = await self.get_model(model_name)
 409
 410         ########################################
 411         # Verify the application doesn't exist #
 412         ########################################
 413         app = await self.get_application(model, application_name)
 414         if app:
 415             raise JujuApplicationExists("Can't deploy application \"{}\" to model \"{}\" because it already exists.".format(application_name, model_name))
 416
 417         ################################################################
 418         # Register this application with the model-level event monitor #
 419         ################################################################
 420         if callback:
 421             self.monitors[model_name].AddApplication(
 422                 application_name,
 423                 callback,
 424                 *callback_args
 425             )
 426
 427         ########################################################
 428         # Check for specific machine placement (native charms) #
 429         ########################################################
 430         to = ""
 431         if machine_spec.keys():
 432             if all(k in machine_spec for k in ['hostname', 'username']):
 433                 # Get the path to the previously generated ssh private key.
 434                 # Machines we're manually provisioned must have N2VC's public
 435                 # key injected, so if we don't have a keypair, raise an error.
 436                 private_key_path = ""
 437
 438                 # Enlist the existing machine in Juju
 439                 machine = await self.model.add_machine(
 440                     spec='ssh:{}@{}:{}'.format(
 441                         specs['host'],
 442                         specs['user'],
 443                         private_key_path,
 444                     )
 445                 )
 446                 # Set the machine id that the deploy below will use.
 447                 to = machine.id
 448             pass
 449
 450         #######################################
 451         # Get the initial charm configuration #
 452         #######################################
 453
 454         rw_mgmt_ip = None
 455         if 'rw_mgmt_ip' in params:
 456             rw_mgmt_ip = params['rw_mgmt_ip']
 457
 458         if 'initial-config-primitive' not in params:
 459             params['initial-config-primitive'] = {}
 460
 461         initial_config = self._get_config_from_dict(
 462             params['initial-config-primitive'],
 463             {'<rw_mgmt_ip>': rw_mgmt_ip}
 464         )
 465
 466         self.log.debug("JujuApi: Deploying charm ({}) from {}".format(
 467             application_name,
 468             charm_path,
 469             to=to,
 470         ))
 471
 472         ########################################################
 473         # Deploy the charm and apply the initial configuration #
 474         ########################################################
 475         app = await model.deploy(
 476             # We expect charm_path to be either the path to the charm on disk
 477             # or in the format of cs:series/name
 478             charm_path,
 479             # This is the formatted, unique name for this charm
 480             application_name=application_name,
 481             # Proxy charms should use the current LTS. This will need to be
 482             # changed for native charms.
 483             series='xenial',
 484             # Apply the initial 'config' primitive during deployment
 485             config=initial_config,
 486             # Where to deploy the charm to.
 487             to=to,
 488         )
 489
 490         # Map the vdu id<->app name,
 491         #
 492         await self.Relate(model_name, vnfd)
 493
 494         # #######################################
 495         # # Execute initial config primitive(s) #
 496         # #######################################
 497         await self.ExecuteInitialPrimitives(
 498             model_name,
 499             application_name,
 500             params,
 501         )
 502
 503         # primitives = {}
 504         #
 505         # # Build a sequential list of the primitives to execute
 506         # for primitive in params['initial-config-primitive']:
 507         #     try:
 508         #         if primitive['name'] == 'config':
 509         #             # This is applied when the Application is deployed
 510         #             pass
 511         #         else:
 512         #             seq = primitive['seq']
 513         #
 514         #             params = {}
 515         #             if 'parameter' in primitive:
 516         #                 params = primitive['parameter']
 517         #
 518         #             primitives[seq] = {
 519         #                 'name': primitive['name'],
 520         #                 'parameters': self._map_primitive_parameters(
 521         #                     params,
 522         #                     {'<rw_mgmt_ip>': rw_mgmt_ip}
 523         #                 ),
 524         #             }
 525         #
 526         #             for primitive in sorted(primitives):
 527         #                 await self.ExecutePrimitive(
 528         #                     model_name,
 529         #                     application_name,
 530         #                     primitives[primitive]['name'],
 531         #                     callback,
 532         #                     callback_args,
 533         #                     **primitives[primitive]['parameters'],
 534         #                 )
 535         #     except N2VCPrimitiveExecutionFailed as e:
 536         #         self.log.debug(
 537         #             "[N2VC] Exception executing primitive: {}".format(e)
 538         #         )
 539         #         raise
 540
 541     async def GetPrimitiveStatus(self, model_name, uuid):
 542         """Get the status of an executed Primitive.
 543
 544         The status of an executed Primitive will be one of three values:
 545         - completed
 546         - failed
 547         - running
 548         """
 549         status = None
 550         try:
 551             if not self.authenticated:
 552                 await self.login()
 553
 554             # FIXME: This is hard-coded until model-per-ns is added
 555             model_name = 'default'
 556
 557             model = await self.get_model(model_name)
 558
 559             results = await model.get_action_status(uuid)
 560
 561             if uuid in results:
 562                 status = results[uuid]
 563
 564         except Exception as e:
 565             self.log.debug(
 566                 "Caught exception while getting primitive status: {}".format(e)
 567             )
 568             raise N2VCPrimitiveExecutionFailed(e)
 569
 570         return status
 571
 572     async def GetPrimitiveOutput(self, model_name, uuid):
 573         """Get the output of an executed Primitive.
 574
 575         Note: this only returns output for a successfully executed primitive.
 576         """
 577         results = None
 578         try:
 579             if not self.authenticated:
 580                 await self.login()
 581
 582             # FIXME: This is hard-coded until model-per-ns is added
 583             model_name = 'default'
 584
 585             model = await self.get_model(model_name)
 586             results = await model.get_action_output(uuid, 60)
 587         except Exception as e:
 588             self.log.debug(
 589                 "Caught exception while getting primitive status: {}".format(e)
 590             )
 591             raise N2VCPrimitiveExecutionFailed(e)
 592
 593         return results
 594
 595     # async def ProvisionMachine(self, model_name, hostname, username):
 596     #     """Provision machine for usage with Juju.
 597     #
 598     #     Provisions a previously instantiated machine for use with Juju.
 599     #     """
 600     #     try:
 601     #         if not self.authenticated:
 602     #             await self.login()
 603     #
 604     #         # FIXME: This is hard-coded until model-per-ns is added
 605     #         model_name = 'default'
 606     #
 607     #         model = await self.get_model(model_name)
 608     #         model.add_machine(spec={})
 609     #
 610     #         machine = await model.add_machine(spec='ssh:{}@{}:{}'.format(
 611     #             "ubuntu",
 612     #             host['address'],
 613     #             private_key_path,
 614     #         ))
 615     #         return machine.id
 616     #
 617     #     except Exception as e:
 618     #         self.log.debug(
 619     #             "Caught exception while getting primitive status: {}".format(e)
 620     #         )
 621     #         raise N2VCPrimitiveExecutionFailed(e)
 622
 623     def GetPrivateKeyPath(self):
 624         homedir = os.environ['HOME']
 625         sshdir = "{}/.ssh".format(homedir)
 626         private_key_path = "{}/id_n2vc_rsa".format(sshdir)
 627         return private_key_path
 628
 629     async def GetPublicKey(self):
 630         """Get the N2VC SSH public key.abs
 631
 632         Returns the SSH public key, to be injected into virtual machines to
 633         be managed by the VCA.
 634
 635         The first time this is run, a ssh keypair will be created. The public
 636         key is injected into a VM so that we can provision the machine with
 637         Juju, after which Juju will communicate with the VM directly via the
 638         juju agent.
 639         """
 640         public_key = ""
 641
 642         # Find the path to where we expect our key to live.
 643         homedir = os.environ['HOME']
 644         sshdir = "{}/.ssh".format(homedir)
 645         if not os.path.exists(sshdir):
 646             os.mkdir(sshdir)
 647
 648         private_key_path = "{}/id_n2vc_rsa".format(sshdir)
 649         public_key_path = "{}.pub".format(private_key_path)
 650
 651         # If we don't have a key generated, generate it.
 652         if not os.path.exists(private_key_path):
 653             cmd = "ssh-keygen -t {} -b {} -N '' -f {}".format(
 654                 "rsa",
 655                 "4096",
 656                 private_key_path
 657             )
 658             subprocess.check_output(shlex.split(cmd))
 659
 660         # Read the public key
 661         with open(public_key_path, "r") as f:
 662             public_key = f.readline()
 663
 664         return public_key
 665
 666     async def ExecuteInitialPrimitives(self, model_name, application_name,
 667                                        params, callback=None, *callback_args):
 668         """Execute multiple primitives.
 669
 670         Execute multiple primitives as declared in initial-config-primitive.
 671         This is useful in cases where the primitives initially failed -- for
 672         example, if the charm is a proxy but the proxy hasn't been configured
 673         yet.
 674         """
 675         uuids = []
 676         primitives = {}
 677
 678         # Build a sequential list of the primitives to execute
 679         for primitive in params['initial-config-primitive']:
 680             try:
 681                 if primitive['name'] == 'config':
 682                     pass
 683                 else:
 684                     seq = primitive['seq']
 685
 686                     params = {}
 687                     if 'parameter' in primitive:
 688                         params = primitive['parameter']
 689
 690                     primitives[seq] = {
 691                         'name': primitive['name'],
 692                         'parameters': self._map_primitive_parameters(
 693                             params,
 694                             {'<rw_mgmt_ip>': None}
 695                         ),
 696                     }
 697
 698                     for primitive in sorted(primitives):
 699                         uuids.append(
 700                             await self.ExecutePrimitive(
 701                                 model_name,
 702                                 application_name,
 703                                 primitives[primitive]['name'],
 704                                 callback,
 705                                 callback_args,
 706                                 **primitives[primitive]['parameters'],
 707                             )
 708                         )
 709             except N2VCPrimitiveExecutionFailed as e:
 710                 self.log.debug(
 711                     "[N2VC] Exception executing primitive: {}".format(e)
 712                 )
 713                 raise
 714         return uuids
 715
 716     async def ExecutePrimitive(self, model_name, application_name, primitive,
 717                                callback, *callback_args, **params):
 718         """Execute a primitive of a charm for Day 1 or Day 2 configuration.
 719
 720         Execute a primitive defined in the VNF descriptor.
 721
 722         :param str model_name: The name of the network service.
 723         :param str application_name: The name of the application
 724         :param str primitive: The name of the primitive to execute.
 725         :param obj callback: A callback function to receive status changes.
 726         :param tuple callback_args: A list of arguments to be passed to the
 727          callback function.
 728         :param dict params: A dictionary of key=value pairs representing the
 729          primitive's parameters
 730           Examples::
 731           {
 732             'rw_mgmt_ip': '1.2.3.4',
 733             # Pass the initial-config-primitives section of the vnf or vdu
 734             'initial-config-primitives': {...}
 735           }
 736         """
 737         self.log.debug("Executing {}".format(primitive))
 738         uuid = None
 739         try:
 740             if not self.authenticated:
 741                 await self.login()
 742
 743             # FIXME: This is hard-coded until model-per-ns is added
 744             model_name = 'default'
 745
 746             model = await self.get_model(model_name)
 747
 748             if primitive == 'config':
 749                 # config is special, and expecting params to be a dictionary
 750                 await self.set_config(
 751                     model,
 752                     application_name,
 753                     params['params'],
 754                 )
 755             else:
 756                 app = await self.get_application(model, application_name)
 757                 if app:
 758                     # Run against the first (and probably only) unit in the app
 759                     unit = app.units[0]
 760                     if unit:
 761                         action = await unit.run_action(primitive, **params)
 762                         uuid = action.id
 763         except Exception as e:
 764             self.log.debug(
 765                 "Caught exception while executing primitive: {}".format(e)
 766             )
 767             raise N2VCPrimitiveExecutionFailed(e)
 768         return uuid
 769
 770     async def RemoveCharms(self, model_name, application_name, callback=None,
 771                            *callback_args):
 772         """Remove a charm from the VCA.
 773
 774         Remove a charm referenced in a VNF Descriptor.
 775
 776         :param str model_name: The name of the network service.
 777         :param str application_name: The name of the application
 778         :param obj callback: A callback function to receive status changes.
 779         :param tuple callback_args: A list of arguments to be passed to the
 780          callback function.
 781         """
 782         try:
 783             if not self.authenticated:
 784                 await self.login()
 785
 786             model = await self.get_model(model_name)
 787             app = await self.get_application(model, application_name)
 788             if app:
 789                 # Remove this application from event monitoring
 790                 self.monitors[model_name].RemoveApplication(application_name)
 791
 792                 # self.notify_callback(model_name, application_name, "removing", callback, *callback_args)
 793                 self.log.debug(
 794                     "Removing the application {}".format(application_name)
 795                 )
 796                 await app.remove()
 797
 798                 # Notify the callback that this charm has been removed.
 799                 self.notify_callback(
 800                     model_name,
 801                     application_name,
 802                     "removed",
 803                     callback,
 804                     *callback_args,
 805                 )
 806
 807         except Exception as e:
 808             print("Caught exception: {}".format(e))
 809             self.log.debug(e)
 810             raise e
 811
 812     async def DestroyNetworkService(self, nsd):
 813         raise NotImplementedError()
 814
 815     async def GetMetrics(self, model_name, application_name):
 816         """Get the metrics collected by the VCA.
 817
 818         :param model_name The name of the model
 819         :param application_name The name of the application
 820         """
 821         metrics = {}
 822         model = await self.get_model(model_name)
 823         app = await self.get_application(model, application_name)
 824         if app:
 825             metrics = await app.get_metrics()
 826
 827         return metrics
 828
 829     async def HasApplication(self, model_name, application_name):
 830         model = await self.get_model(model_name)
 831         app = await self.get_application(model, application_name)
 832         if app:
 833             return True
 834         return False
 835
 836     # Non-public methods
 837     async def add_relation(self, model_name, relation1, relation2):
 838         """
 839         Add a relation between two application endpoints.
 840
 841         :param str model_name Name of the network service.
 842         :param str relation1 '<application>[:<relation_name>]'
 843         :param str relation12 '<application>[:<relation_name>]'
 844         """
 845
 846         if not self.authenticated:
 847             await self.login()
 848
 849         m = await self.get_model(model_name)
 850         try:
 851             await m.add_relation(relation1, relation2)
 852         except JujuAPIError as e:
 853             # If one of the applications in the relationship doesn't exist,
 854             # or the relation has already been added, let the operation fail
 855             # silently.
 856             if 'not found' in e.message:
 857                 return
 858             if 'already exists' in e.message:
 859                 return
 860
 861             raise e
 862
 863     # async def apply_config(self, config, application):
 864     #     """Apply a configuration to the application."""
 865     #     print("JujuApi: Applying configuration to {}.".format(
 866     #         application
 867     #     ))
 868     #     return await self.set_config(application=application, config=config)
 869
 870     def _get_config_from_dict(self, config_primitive, values):
 871         """Transform the yang config primitive to dict.
 872
 873         Expected result:
 874
 875             config = {
 876                 'config':
 877             }
 878         """
 879         config = {}
 880         for primitive in config_primitive:
 881             if primitive['name'] == 'config':
 882                 # config = self._map_primitive_parameters()
 883                 for parameter in primitive['parameter']:
 884                     param = str(parameter['name'])
 885                     if parameter['value'] == "<rw_mgmt_ip>":
 886                         config[param] = str(values[parameter['value']])
 887                     else:
 888                         config[param] = str(parameter['value'])
 889
 890         return config
 891
 892     def _map_primitive_parameters(self, parameters, values):
 893         params = {}
 894         for parameter in parameters:
 895             param = str(parameter['name'])
 896
 897             # Typecast parameter value, if present
 898             if 'data-type' in parameter:
 899                 paramtype = str(parameter['data-type']).lower()
 900                 value = None
 901
 902                 if paramtype == "integer":
 903                     value = int(parameter['value'])
 904                 elif paramtype == "boolean":
 905                     value = bool(parameter['value'])
 906                 else:
 907                     value = str(parameter['value'])
 908
 909             if parameter['value'] == "<rw_mgmt_ip>":
 910                 params[param] = str(values[parameter['value']])
 911             else:
 912                 params[param] = value
 913         return params
 914
 915     def _get_config_from_yang(self, config_primitive, values):
 916         """Transform the yang config primitive to dict."""
 917         config = {}
 918         for primitive in config_primitive.values():
 919             if primitive['name'] == 'config':
 920                 for parameter in primitive['parameter'].values():
 921                     param = str(parameter['name'])
 922                     if parameter['value'] == "<rw_mgmt_ip>":
 923                         config[param] = str(values[parameter['value']])
 924                     else:
 925                         config[param] = str(parameter['value'])
 926
 927         return config
 928
 929     def FormatApplicationName(self, *args):
 930         """
 931         Generate a Juju-compatible Application name
 932
 933         :param args tuple: Positional arguments to be used to construct the
 934         application name.
 935
 936         Limitations::
 937         - Only accepts characters a-z and non-consequitive dashes (-)
 938         - Application name should not exceed 50 characters
 939
 940         Examples::
 941
 942             FormatApplicationName("ping_pong_ns", "ping_vnf", "a")
 943         """
 944         appname = ""
 945         for c in "-".join(list(args)):
 946             if c.isdigit():
 947                 c = chr(97 + int(c))
 948             elif not c.isalpha():
 949                 c = "-"
 950             appname += c
 951         return re.sub('\-+', '-', appname.lower())
 952
 953     # def format_application_name(self, nsd_name, vnfr_name, member_vnf_index=0):
 954     #     """Format the name of the application
 955     #
 956     #     Limitations:
 957     #     - Only accepts characters a-z and non-consequitive dashes (-)
 958     #     - Application name should not exceed 50 characters
 959     #     """
 960     #     name = "{}-{}-{}".format(nsd_name, vnfr_name, member_vnf_index)
 961     #     new_name = ''
 962     #     for c in name:
 963     #         if c.isdigit():
 964     #             c = chr(97 + int(c))
 965     #         elif not c.isalpha():
 966     #             c = "-"
 967     #         new_name += c
 968     #     return re.sub('\-+', '-', new_name.lower())
 969
 970     def format_model_name(self, name):
 971         """Format the name of model.
 972
 973         Model names may only contain lowercase letters, digits and hyphens
 974         """
 975
 976         return name.replace('_', '-').lower()
 977
 978     async def get_application(self, model, application):
 979         """Get the deployed application."""
 980         if not self.authenticated:
 981             await self.login()
 982
 983         app = None
 984         if application and model:
 985             if model.applications:
 986                 if application in model.applications:
 987                     app = model.applications[application]
 988
 989         return app
 990
 991     async def get_model(self, model_name='default'):
 992         """Get a model from the Juju Controller.
 993
 994         Note: Model objects returned must call disconnected() before it goes
 995         out of scope."""
 996         if not self.authenticated:
 997             await self.login()
 998
 999         if model_name not in self.models:
1000             self.models[model_name] = await self.controller.get_model(
1001                 model_name,
1002             )
1003             self.refcount['model'] += 1
1004
1005             # Create an observer for this model
1006             self.monitors[model_name] = VCAMonitor(model_name)
1007             self.models[model_name].add_observer(self.monitors[model_name])
1008
1009         return self.models[model_name]
1010
1011     async def login(self):
1012         """Login to the Juju controller."""
1013
1014         if self.authenticated:
1015             return
1016
1017         self.connecting = True
1018
1019         self.log.debug("JujuApi: Logging into controller")
1020
1021         cacert = None
1022         self.controller = Controller(loop=self.loop)
1023
1024         if self.secret:
1025             self.log.debug(
1026                 "Connecting to controller... ws://{}:{} as {}/{}".format(
1027                     self.endpoint,
1028                     self.port,
1029                     self.user,
1030                     self.secret,
1031                 )
1032             )
1033             await self.controller.connect(
1034                 endpoint=self.endpoint,
1035                 username=self.user,
1036                 password=self.secret,
1037                 cacert=cacert,
1038             )
1039             self.refcount['controller'] += 1
1040         else:
1041             # current_controller no longer exists
1042             # self.log.debug("Connecting to current controller...")
1043             # await self.controller.connect_current()
1044             # await self.controller.connect(
1045             #     endpoint=self.endpoint,
1046             #     username=self.user,
1047             #     cacert=cacert,
1048             # )
1049             self.log.fatal("VCA credentials not configured.")
1050
1051         self.authenticated = True
1052         self.log.debug("JujuApi: Logged into controller")
1053
1054     async def logout(self):
1055         """Logout of the Juju controller."""
1056         if not self.authenticated:
1057             return
1058
1059         try:
1060             if self.default_model:
1061                 self.log.debug("Disconnecting model {}".format(
1062                     self.default_model
1063                 ))
1064                 await self.default_model.disconnect()
1065                 self.refcount['model'] -= 1
1066                 self.default_model = None
1067
1068             for model in self.models:
1069                 await self.models[model].disconnect()
1070                 self.refcount['model'] -= 1
1071                 self.models[model] = None
1072
1073             if self.controller:
1074                 self.log.debug("Disconnecting controller {}".format(
1075                     self.controller
1076                 ))
1077                 await self.controller.disconnect()
1078                 self.refcount['controller'] -= 1
1079                 self.controller = None
1080
1081             self.authenticated = False
1082
1083             self.log.debug(self.refcount)
1084
1085         except Exception as e:
1086             self.log.fatal(
1087                 "Fatal error logging out of Juju Controller: {}".format(e)
1088             )
1089             raise e
1090
1091     # async def remove_application(self, name):
1092     #     """Remove the application."""
1093     #     if not self.authenticated:
1094     #         await self.login()
1095     #
1096     #     app = await self.get_application(name)
1097     #     if app:
1098     #         self.log.debug("JujuApi: Destroying application {}".format(
1099     #             name,
1100     #         ))
1101     #
1102     #         await app.destroy()
1103
1104     async def remove_relation(self, a, b):
1105         """
1106         Remove a relation between two application endpoints
1107
1108         :param a An application endpoint
1109         :param b An application endpoint
1110         """
1111         if not self.authenticated:
1112             await self.login()
1113
1114         m = await self.get_model()
1115         try:
1116             m.remove_relation(a, b)
1117         finally:
1118             await m.disconnect()
1119
1120     async def resolve_error(self, application=None):
1121         """Resolve units in error state."""
1122         if not self.authenticated:
1123             await self.login()
1124
1125         app = await self.get_application(self.default_model, application)
1126         if app:
1127             self.log.debug(
1128                 "JujuApi: Resolving errors for application {}".format(
1129                     application,
1130                 )
1131             )
1132
1133             for unit in app.units:
1134                 app.resolved(retry=True)
1135
1136     async def run_action(self, application, action_name, **params):
1137         """Execute an action and return an Action object."""
1138         if not self.authenticated:
1139             await self.login()
1140         result = {
1141             'status': '',
1142             'action': {
1143                 'tag': None,
1144                 'results': None,
1145             }
1146         }
1147         app = await self.get_application(self.default_model, application)
1148         if app:
1149             # We currently only have one unit per application
1150             # so use the first unit available.
1151             unit = app.units[0]
1152
1153             self.log.debug(
1154                 "JujuApi: Running Action {} against Application {}".format(
1155                     action_name,
1156                     application,
1157                 )
1158             )
1159
1160             action = await unit.run_action(action_name, **params)
1161
1162             # Wait for the action to complete
1163             await action.wait()
1164
1165             result['status'] = action.status
1166             result['action']['tag'] = action.data['id']
1167             result['action']['results'] = action.results
1168
1169         return result
1170
1171     async def set_config(self, model_name, application, config):
1172         """Apply a configuration to the application."""
1173         if not self.authenticated:
1174             await self.login()
1175
1176         app = await self.get_application(model_name, application)
1177         if app:
1178             self.log.debug("JujuApi: Setting config for Application {}".format(
1179                 application,
1180             ))
1181             await app.set_config(config)
1182
1183             # Verify the config is set
1184             newconf = await app.get_config()
1185             for key in config:
1186                 if config[key] != newconf[key]['value']:
1187                     self.log.debug("JujuApi: Config not set! Key {} Value {} doesn't match {}".format(key, config[key], newconf[key]))
1188
1189     # async def set_parameter(self, parameter, value, application=None):
1190     #     """Set a config parameter for a service."""
1191     #     if not self.authenticated:
1192     #         await self.login()
1193     #
1194     #     self.log.debug("JujuApi: Setting {}={} for Application {}".format(
1195     #         parameter,
1196     #         value,
1197     #         application,
1198     #     ))
1199     #     return await self.apply_config(
1200     #         {parameter: value},
1201     #         application=application,
1202         # )
1203
1204     async def wait_for_application(self, model_name, application_name,
1205                                    timeout=300):
1206         """Wait for an application to become active."""
1207         if not self.authenticated:
1208             await self.login()
1209
1210         # TODO: In a point release, we will use a model per deployed network
1211         # service. In the meantime, we will always use the 'default' model.
1212         model_name = 'default'
1213         model = await self.get_model(model_name)
1214
1215         app = await self.get_application(model, application_name)
1216         self.log.debug("Application: {}".format(app))
1217         # app = await self.get_application(model_name, application_name)
1218         if app:
1219             self.log.debug(
1220                 "JujuApi: Waiting {} seconds for Application {}".format(
1221                     timeout,
1222                     application_name,
1223                 )
1224             )
1225
1226             await model.block_until(
1227                 lambda: all(
1228                     unit.agent_status == 'idle' and unit.workload_status in
1229                     ['active', 'unknown'] for unit in app.units
1230                 ),
1231                 timeout=timeout
1232             )