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 ['host', 'user']):
 433                 # Enlist an existing machine as a Juju unit
 434                 machine = await model.add_machine(spec='ssh:{}@{}:{}'.format(
 435                     machine_spec['user'],
 436                     machine_spec['host'],
 437                     self.GetPrivateKeyPath(),
 438                 ))
 439                 to = machine.id
 440
 441         #######################################
 442         # Get the initial charm configuration #
 443         #######################################
 444
 445         rw_mgmt_ip = None
 446         if 'rw_mgmt_ip' in params:
 447             rw_mgmt_ip = params['rw_mgmt_ip']
 448
 449         if 'initial-config-primitive' not in params:
 450             params['initial-config-primitive'] = {}
 451
 452         initial_config = self._get_config_from_dict(
 453             params['initial-config-primitive'],
 454             {'<rw_mgmt_ip>': rw_mgmt_ip}
 455         )
 456
 457         self.log.debug("JujuApi: Deploying charm ({}) from {}".format(
 458             application_name,
 459             charm_path,
 460             to=to,
 461         ))
 462
 463         ########################################################
 464         # Deploy the charm and apply the initial configuration #
 465         ########################################################
 466         app = await model.deploy(
 467             # We expect charm_path to be either the path to the charm on disk
 468             # or in the format of cs:series/name
 469             charm_path,
 470             # This is the formatted, unique name for this charm
 471             application_name=application_name,
 472             # Proxy charms should use the current LTS. This will need to be
 473             # changed for native charms.
 474             series='xenial',
 475             # Apply the initial 'config' primitive during deployment
 476             config=initial_config,
 477             # Where to deploy the charm to.
 478             to=to,
 479         )
 480
 481         # Map the vdu id<->app name,
 482         #
 483         await self.Relate(model_name, vnfd)
 484
 485         # #######################################
 486         # # Execute initial config primitive(s) #
 487         # #######################################
 488         uuids = await self.ExecuteInitialPrimitives(
 489             model_name,
 490             application_name,
 491             params,
 492         )
 493         return uuids
 494
 495         # primitives = {}
 496         #
 497         # # Build a sequential list of the primitives to execute
 498         # for primitive in params['initial-config-primitive']:
 499         #     try:
 500         #         if primitive['name'] == 'config':
 501         #             # This is applied when the Application is deployed
 502         #             pass
 503         #         else:
 504         #             seq = primitive['seq']
 505         #
 506         #             params = {}
 507         #             if 'parameter' in primitive:
 508         #                 params = primitive['parameter']
 509         #
 510         #             primitives[seq] = {
 511         #                 'name': primitive['name'],
 512         #                 'parameters': self._map_primitive_parameters(
 513         #                     params,
 514         #                     {'<rw_mgmt_ip>': rw_mgmt_ip}
 515         #                 ),
 516         #             }
 517         #
 518         #             for primitive in sorted(primitives):
 519         #                 await self.ExecutePrimitive(
 520         #                     model_name,
 521         #                     application_name,
 522         #                     primitives[primitive]['name'],
 523         #                     callback,
 524         #                     callback_args,
 525         #                     **primitives[primitive]['parameters'],
 526         #                 )
 527         #     except N2VCPrimitiveExecutionFailed as e:
 528         #         self.log.debug(
 529         #             "[N2VC] Exception executing primitive: {}".format(e)
 530         #         )
 531         #         raise
 532
 533     async def GetPrimitiveStatus(self, model_name, uuid):
 534         """Get the status of an executed Primitive.
 535
 536         The status of an executed Primitive will be one of three values:
 537         - completed
 538         - failed
 539         - running
 540         """
 541         status = None
 542         try:
 543             if not self.authenticated:
 544                 await self.login()
 545
 546             # FIXME: This is hard-coded until model-per-ns is added
 547             model_name = 'default'
 548
 549             model = await self.get_model(model_name)
 550
 551             results = await model.get_action_status(uuid)
 552
 553             if uuid in results:
 554                 status = results[uuid]
 555
 556         except Exception as e:
 557             self.log.debug(
 558                 "Caught exception while getting primitive status: {}".format(e)
 559             )
 560             raise N2VCPrimitiveExecutionFailed(e)
 561
 562         return status
 563
 564     async def GetPrimitiveOutput(self, model_name, uuid):
 565         """Get the output of an executed Primitive.
 566
 567         Note: this only returns output for a successfully executed primitive.
 568         """
 569         results = None
 570         try:
 571             if not self.authenticated:
 572                 await self.login()
 573
 574             # FIXME: This is hard-coded until model-per-ns is added
 575             model_name = 'default'
 576
 577             model = await self.get_model(model_name)
 578             results = await model.get_action_output(uuid, 60)
 579         except Exception as e:
 580             self.log.debug(
 581                 "Caught exception while getting primitive status: {}".format(e)
 582             )
 583             raise N2VCPrimitiveExecutionFailed(e)
 584
 585         return results
 586
 587     # async def ProvisionMachine(self, model_name, hostname, username):
 588     #     """Provision machine for usage with Juju.
 589     #
 590     #     Provisions a previously instantiated machine for use with Juju.
 591     #     """
 592     #     try:
 593     #         if not self.authenticated:
 594     #             await self.login()
 595     #
 596     #         # FIXME: This is hard-coded until model-per-ns is added
 597     #         model_name = 'default'
 598     #
 599     #         model = await self.get_model(model_name)
 600     #         model.add_machine(spec={})
 601     #
 602     #         machine = await model.add_machine(spec='ssh:{}@{}:{}'.format(
 603     #             "ubuntu",
 604     #             host['address'],
 605     #             private_key_path,
 606     #         ))
 607     #         return machine.id
 608     #
 609     #     except Exception as e:
 610     #         self.log.debug(
 611     #             "Caught exception while getting primitive status: {}".format(e)
 612     #         )
 613     #         raise N2VCPrimitiveExecutionFailed(e)
 614
 615     def GetPrivateKeyPath(self):
 616         homedir = os.environ['HOME']
 617         sshdir = "{}/.ssh".format(homedir)
 618         private_key_path = "{}/id_n2vc_rsa".format(sshdir)
 619         return private_key_path
 620
 621     async def GetPublicKey(self):
 622         """Get the N2VC SSH public key.abs
 623
 624         Returns the SSH public key, to be injected into virtual machines to
 625         be managed by the VCA.
 626
 627         The first time this is run, a ssh keypair will be created. The public
 628         key is injected into a VM so that we can provision the machine with
 629         Juju, after which Juju will communicate with the VM directly via the
 630         juju agent.
 631         """
 632         public_key = ""
 633
 634         # Find the path to where we expect our key to live.
 635         homedir = os.environ['HOME']
 636         sshdir = "{}/.ssh".format(homedir)
 637         if not os.path.exists(sshdir):
 638             os.mkdir(sshdir)
 639
 640         private_key_path = "{}/id_n2vc_rsa".format(sshdir)
 641         public_key_path = "{}.pub".format(private_key_path)
 642
 643         # If we don't have a key generated, generate it.
 644         if not os.path.exists(private_key_path):
 645             cmd = "ssh-keygen -t {} -b {} -N '' -f {}".format(
 646                 "rsa",
 647                 "4096",
 648                 private_key_path
 649             )
 650             subprocess.check_output(shlex.split(cmd))
 651
 652         # Read the public key
 653         with open(public_key_path, "r") as f:
 654             public_key = f.readline()
 655
 656         return public_key
 657
 658     async def ExecuteInitialPrimitives(self, model_name, application_name,
 659                                        params, callback=None, *callback_args):
 660         """Execute multiple primitives.
 661
 662         Execute multiple primitives as declared in initial-config-primitive.
 663         This is useful in cases where the primitives initially failed -- for
 664         example, if the charm is a proxy but the proxy hasn't been configured
 665         yet.
 666         """
 667         uuids = []
 668         primitives = {}
 669
 670         # Build a sequential list of the primitives to execute
 671         for primitive in params['initial-config-primitive']:
 672             try:
 673                 if primitive['name'] == 'config':
 674                     pass
 675                 else:
 676                     seq = primitive['seq']
 677
 678                     params = {}
 679                     if 'parameter' in primitive:
 680                         params = primitive['parameter']
 681
 682                     primitives[seq] = {
 683                         'name': primitive['name'],
 684                         'parameters': self._map_primitive_parameters(
 685                             params,
 686                             {'<rw_mgmt_ip>': None}
 687                         ),
 688                     }
 689
 690                     for primitive in sorted(primitives):
 691                         uuids.append(
 692                             await self.ExecutePrimitive(
 693                                 model_name,
 694                                 application_name,
 695                                 primitives[primitive]['name'],
 696                                 callback,
 697                                 callback_args,
 698                                 **primitives[primitive]['parameters'],
 699                             )
 700                         )
 701             except N2VCPrimitiveExecutionFailed as e:
 702                 self.log.debug(
 703                     "[N2VC] Exception executing primitive: {}".format(e)
 704                 )
 705                 raise
 706         return uuids
 707
 708     async def ExecutePrimitive(self, model_name, application_name, primitive,
 709                                callback, *callback_args, **params):
 710         """Execute a primitive of a charm for Day 1 or Day 2 configuration.
 711
 712         Execute a primitive defined in the VNF descriptor.
 713
 714         :param str model_name: The name of the network service.
 715         :param str application_name: The name of the application
 716         :param str primitive: The name of the primitive to execute.
 717         :param obj callback: A callback function to receive status changes.
 718         :param tuple callback_args: A list of arguments to be passed to the
 719          callback function.
 720         :param dict params: A dictionary of key=value pairs representing the
 721          primitive's parameters
 722           Examples::
 723           {
 724             'rw_mgmt_ip': '1.2.3.4',
 725             # Pass the initial-config-primitives section of the vnf or vdu
 726             'initial-config-primitives': {...}
 727           }
 728         """
 729         self.log.debug("Executing {}".format(primitive))
 730         uuid = None
 731         try:
 732             if not self.authenticated:
 733                 await self.login()
 734
 735             # FIXME: This is hard-coded until model-per-ns is added
 736             model_name = 'default'
 737
 738             model = await self.get_model(model_name)
 739
 740             if primitive == 'config':
 741                 # config is special, and expecting params to be a dictionary
 742                 await self.set_config(
 743                     model,
 744                     application_name,
 745                     params['params'],
 746                 )
 747             else:
 748                 app = await self.get_application(model, application_name)
 749                 if app:
 750                     # Run against the first (and probably only) unit in the app
 751                     unit = app.units[0]
 752                     if unit:
 753                         action = await unit.run_action(primitive, **params)
 754                         uuid = action.id
 755         except Exception as e:
 756             self.log.debug(
 757                 "Caught exception while executing primitive: {}".format(e)
 758             )
 759             raise N2VCPrimitiveExecutionFailed(e)
 760         return uuid
 761
 762     async def RemoveCharms(self, model_name, application_name, callback=None,
 763                            *callback_args):
 764         """Remove a charm from the VCA.
 765
 766         Remove a charm referenced in a VNF Descriptor.
 767
 768         :param str model_name: The name of the network service.
 769         :param str application_name: The name of the application
 770         :param obj callback: A callback function to receive status changes.
 771         :param tuple callback_args: A list of arguments to be passed to the
 772          callback function.
 773         """
 774         try:
 775             if not self.authenticated:
 776                 await self.login()
 777
 778             model = await self.get_model(model_name)
 779             app = await self.get_application(model, application_name)
 780             if app:
 781                 # Remove this application from event monitoring
 782                 self.monitors[model_name].RemoveApplication(application_name)
 783
 784                 # self.notify_callback(model_name, application_name, "removing", callback, *callback_args)
 785                 self.log.debug(
 786                     "Removing the application {}".format(application_name)
 787                 )
 788                 await app.remove()
 789
 790                 # Notify the callback that this charm has been removed.
 791                 self.notify_callback(
 792                     model_name,
 793                     application_name,
 794                     "removed",
 795                     callback,
 796                     *callback_args,
 797                 )
 798
 799         except Exception as e:
 800             print("Caught exception: {}".format(e))
 801             self.log.debug(e)
 802             raise e
 803
 804     async def DestroyNetworkService(self, nsd):
 805         raise NotImplementedError()
 806
 807     async def GetMetrics(self, model_name, application_name):
 808         """Get the metrics collected by the VCA.
 809
 810         :param model_name The name of the model
 811         :param application_name The name of the application
 812         """
 813         metrics = {}
 814         model = await self.get_model(model_name)
 815         app = await self.get_application(model, application_name)
 816         if app:
 817             metrics = await app.get_metrics()
 818
 819         return metrics
 820
 821     async def HasApplication(self, model_name, application_name):
 822         model = await self.get_model(model_name)
 823         app = await self.get_application(model, application_name)
 824         if app:
 825             return True
 826         return False
 827
 828     # Non-public methods
 829     async def add_relation(self, model_name, relation1, relation2):
 830         """
 831         Add a relation between two application endpoints.
 832
 833         :param str model_name Name of the network service.
 834         :param str relation1 '<application>[:<relation_name>]'
 835         :param str relation12 '<application>[:<relation_name>]'
 836         """
 837
 838         if not self.authenticated:
 839             await self.login()
 840
 841         m = await self.get_model(model_name)
 842         try:
 843             await m.add_relation(relation1, relation2)
 844         except JujuAPIError as e:
 845             # If one of the applications in the relationship doesn't exist,
 846             # or the relation has already been added, let the operation fail
 847             # silently.
 848             if 'not found' in e.message:
 849                 return
 850             if 'already exists' in e.message:
 851                 return
 852
 853             raise e
 854
 855     # async def apply_config(self, config, application):
 856     #     """Apply a configuration to the application."""
 857     #     print("JujuApi: Applying configuration to {}.".format(
 858     #         application
 859     #     ))
 860     #     return await self.set_config(application=application, config=config)
 861
 862     def _get_config_from_dict(self, config_primitive, values):
 863         """Transform the yang config primitive to dict.
 864
 865         Expected result:
 866
 867             config = {
 868                 'config':
 869             }
 870         """
 871         config = {}
 872         for primitive in config_primitive:
 873             if primitive['name'] == 'config':
 874                 # config = self._map_primitive_parameters()
 875                 for parameter in primitive['parameter']:
 876                     param = str(parameter['name'])
 877                     if parameter['value'] == "<rw_mgmt_ip>":
 878                         config[param] = str(values[parameter['value']])
 879                     else:
 880                         config[param] = str(parameter['value'])
 881
 882         return config
 883
 884     def _map_primitive_parameters(self, parameters, values):
 885         params = {}
 886         for parameter in parameters:
 887             param = str(parameter['name'])
 888             value = None
 889
 890             # Typecast parameter value, if present
 891             if 'data-type' in parameter:
 892                 paramtype = str(parameter['data-type']).lower()
 893
 894                 if paramtype == "integer":
 895                     value = int(parameter['value'])
 896                 elif paramtype == "boolean":
 897                     value = bool(parameter['value'])
 898                 else:
 899                     value = str(parameter['value'])
 900
 901             if parameter['value'] == "<rw_mgmt_ip>":
 902                 params[param] = str(values[parameter['value']])
 903             else:
 904                 params[param] = value
 905         return params
 906
 907     def _get_config_from_yang(self, config_primitive, values):
 908         """Transform the yang config primitive to dict."""
 909         config = {}
 910         for primitive in config_primitive.values():
 911             if primitive['name'] == 'config':
 912                 for parameter in primitive['parameter'].values():
 913                     param = str(parameter['name'])
 914                     if parameter['value'] == "<rw_mgmt_ip>":
 915                         config[param] = str(values[parameter['value']])
 916                     else:
 917                         config[param] = str(parameter['value'])
 918
 919         return config
 920
 921     def FormatApplicationName(self, *args):
 922         """
 923         Generate a Juju-compatible Application name
 924
 925         :param args tuple: Positional arguments to be used to construct the
 926         application name.
 927
 928         Limitations::
 929         - Only accepts characters a-z and non-consequitive dashes (-)
 930         - Application name should not exceed 50 characters
 931
 932         Examples::
 933
 934             FormatApplicationName("ping_pong_ns", "ping_vnf", "a")
 935         """
 936         appname = ""
 937         for c in "-".join(list(args)):
 938             if c.isdigit():
 939                 c = chr(97 + int(c))
 940             elif not c.isalpha():
 941                 c = "-"
 942             appname += c
 943         return re.sub('\-+', '-', appname.lower())
 944
 945     # def format_application_name(self, nsd_name, vnfr_name, member_vnf_index=0):
 946     #     """Format the name of the application
 947     #
 948     #     Limitations:
 949     #     - Only accepts characters a-z and non-consequitive dashes (-)
 950     #     - Application name should not exceed 50 characters
 951     #     """
 952     #     name = "{}-{}-{}".format(nsd_name, vnfr_name, member_vnf_index)
 953     #     new_name = ''
 954     #     for c in name:
 955     #         if c.isdigit():
 956     #             c = chr(97 + int(c))
 957     #         elif not c.isalpha():
 958     #             c = "-"
 959     #         new_name += c
 960     #     return re.sub('\-+', '-', new_name.lower())
 961
 962     def format_model_name(self, name):
 963         """Format the name of model.
 964
 965         Model names may only contain lowercase letters, digits and hyphens
 966         """
 967
 968         return name.replace('_', '-').lower()
 969
 970     async def get_application(self, model, application):
 971         """Get the deployed application."""
 972         if not self.authenticated:
 973             await self.login()
 974
 975         app = None
 976         if application and model:
 977             if model.applications:
 978                 if application in model.applications:
 979                     app = model.applications[application]
 980
 981         return app
 982
 983     async def get_model(self, model_name='default'):
 984         """Get a model from the Juju Controller.
 985
 986         Note: Model objects returned must call disconnected() before it goes
 987         out of scope."""
 988         if not self.authenticated:
 989             await self.login()
 990
 991         if model_name not in self.models:
 992             self.models[model_name] = await self.controller.get_model(
 993                 model_name,
 994             )
 995             self.refcount['model'] += 1
 996
 997             # Create an observer for this model
 998             self.monitors[model_name] = VCAMonitor(model_name)
 999             self.models[model_name].add_observer(self.monitors[model_name])
1000
1001         return self.models[model_name]
1002
1003     async def login(self):
1004         """Login to the Juju controller."""
1005
1006         if self.authenticated:
1007             return
1008
1009         self.connecting = True
1010
1011         self.log.debug("JujuApi: Logging into controller")
1012
1013         cacert = None
1014         self.controller = Controller(loop=self.loop)
1015
1016         if self.secret:
1017             self.log.debug(
1018                 "Connecting to controller... ws://{}:{} as {}/{}".format(
1019                     self.endpoint,
1020                     self.port,
1021                     self.user,
1022                     self.secret,
1023                 )
1024             )
1025             await self.controller.connect(
1026                 endpoint=self.endpoint,
1027                 username=self.user,
1028                 password=self.secret,
1029                 cacert=cacert,
1030             )
1031             self.refcount['controller'] += 1
1032         else:
1033             # current_controller no longer exists
1034             # self.log.debug("Connecting to current controller...")
1035             # await self.controller.connect_current()
1036             # await self.controller.connect(
1037             #     endpoint=self.endpoint,
1038             #     username=self.user,
1039             #     cacert=cacert,
1040             # )
1041             self.log.fatal("VCA credentials not configured.")
1042
1043         self.authenticated = True
1044         self.log.debug("JujuApi: Logged into controller")
1045
1046     async def logout(self):
1047         """Logout of the Juju controller."""
1048         if not self.authenticated:
1049             return
1050
1051         try:
1052             if self.default_model:
1053                 self.log.debug("Disconnecting model {}".format(
1054                     self.default_model
1055                 ))
1056                 await self.default_model.disconnect()
1057                 self.refcount['model'] -= 1
1058                 self.default_model = None
1059
1060             for model in self.models:
1061                 await self.models[model].disconnect()
1062                 self.refcount['model'] -= 1
1063                 self.models[model] = None
1064
1065             if self.controller:
1066                 self.log.debug("Disconnecting controller {}".format(
1067                     self.controller
1068                 ))
1069                 await self.controller.disconnect()
1070                 self.refcount['controller'] -= 1
1071                 self.controller = None
1072
1073             self.authenticated = False
1074
1075             self.log.debug(self.refcount)
1076
1077         except Exception as e:
1078             self.log.fatal(
1079                 "Fatal error logging out of Juju Controller: {}".format(e)
1080             )
1081             raise e
1082
1083     # async def remove_application(self, name):
1084     #     """Remove the application."""
1085     #     if not self.authenticated:
1086     #         await self.login()
1087     #
1088     #     app = await self.get_application(name)
1089     #     if app:
1090     #         self.log.debug("JujuApi: Destroying application {}".format(
1091     #             name,
1092     #         ))
1093     #
1094     #         await app.destroy()
1095
1096     async def remove_relation(self, a, b):
1097         """
1098         Remove a relation between two application endpoints
1099
1100         :param a An application endpoint
1101         :param b An application endpoint
1102         """
1103         if not self.authenticated:
1104             await self.login()
1105
1106         m = await self.get_model()
1107         try:
1108             m.remove_relation(a, b)
1109         finally:
1110             await m.disconnect()
1111
1112     async def resolve_error(self, application=None):
1113         """Resolve units in error state."""
1114         if not self.authenticated:
1115             await self.login()
1116
1117         app = await self.get_application(self.default_model, application)
1118         if app:
1119             self.log.debug(
1120                 "JujuApi: Resolving errors for application {}".format(
1121                     application,
1122                 )
1123             )
1124
1125             for unit in app.units:
1126                 app.resolved(retry=True)
1127
1128     async def run_action(self, application, action_name, **params):
1129         """Execute an action and return an Action object."""
1130         if not self.authenticated:
1131             await self.login()
1132         result = {
1133             'status': '',
1134             'action': {
1135                 'tag': None,
1136                 'results': None,
1137             }
1138         }
1139         app = await self.get_application(self.default_model, application)
1140         if app:
1141             # We currently only have one unit per application
1142             # so use the first unit available.
1143             unit = app.units[0]
1144
1145             self.log.debug(
1146                 "JujuApi: Running Action {} against Application {}".format(
1147                     action_name,
1148                     application,
1149                 )
1150             )
1151
1152             action = await unit.run_action(action_name, **params)
1153
1154             # Wait for the action to complete
1155             await action.wait()
1156
1157             result['status'] = action.status
1158             result['action']['tag'] = action.data['id']
1159             result['action']['results'] = action.results
1160
1161         return result
1162
1163     async def set_config(self, model_name, application, config):
1164         """Apply a configuration to the application."""
1165         if not self.authenticated:
1166             await self.login()
1167
1168         app = await self.get_application(model_name, application)
1169         if app:
1170             self.log.debug("JujuApi: Setting config for Application {}".format(
1171                 application,
1172             ))
1173             await app.set_config(config)
1174
1175             # Verify the config is set
1176             newconf = await app.get_config()
1177             for key in config:
1178                 if config[key] != newconf[key]['value']:
1179                     self.log.debug("JujuApi: Config not set! Key {} Value {} doesn't match {}".format(key, config[key], newconf[key]))
1180
1181     # async def set_parameter(self, parameter, value, application=None):
1182     #     """Set a config parameter for a service."""
1183     #     if not self.authenticated:
1184     #         await self.login()
1185     #
1186     #     self.log.debug("JujuApi: Setting {}={} for Application {}".format(
1187     #         parameter,
1188     #         value,
1189     #         application,
1190     #     ))
1191     #     return await self.apply_config(
1192     #         {parameter: value},
1193     #         application=application,
1194         # )
1195
1196     async def wait_for_application(self, model_name, application_name,
1197                                    timeout=300):
1198         """Wait for an application to become active."""
1199         if not self.authenticated:
1200             await self.login()
1201
1202         # TODO: In a point release, we will use a model per deployed network
1203         # service. In the meantime, we will always use the 'default' model.
1204         model_name = 'default'
1205         model = await self.get_model(model_name)
1206
1207         app = await self.get_application(model, application_name)
1208         self.log.debug("Application: {}".format(app))
1209         # app = await self.get_application(model_name, application_name)
1210         if app:
1211             self.log.debug(
1212                 "JujuApi: Waiting {} seconds for Application {}".format(
1213                     timeout,
1214                     application_name,
1215                 )
1216             )
1217
1218             await model.block_until(
1219                 lambda: all(
1220                     unit.agent_status == 'idle' and unit.workload_status in
1221                     ['active', 'unknown'] for unit in app.units
1222                 ),
1223                 timeout=timeout
1224             )