n2vc/vnf.py

   1
   2 import logging
   3 import os
   4 import os.path
   5 import re
   6 import ssl
   7 import sys
   8 import time
   9
  10 # FIXME: this should load the juju inside or modules without having to
  11 # explicitly install it. Check why it's not working.
  12 # Load our subtree of the juju library
  13 path = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
  14 path = os.path.join(path, "modules/libjuju/")
  15 if path not in sys.path:
  16     sys.path.insert(1, path)
  17
  18 from juju.controller import Controller
  19 from juju.model import Model, ModelObserver
  20
  21
  22 # We might need this to connect to the websocket securely, but test and verify.
  23 try:
  24     ssl._create_default_https_context = ssl._create_unverified_context
  25 except AttributeError:
  26     # Legacy Python doesn't verify by default (see pep-0476)
  27     #   https://www.python.org/dev/peps/pep-0476/
  28     pass
  29
  30
  31 # Custom exceptions
  32 class JujuCharmNotFound(Exception):
  33     """The Charm can't be found or is not readable."""
  34
  35
  36 class JujuApplicationExists(Exception):
  37     """The Application already exists."""
  38
  39
  40 class N2VCPrimitiveExecutionFailed(Exception):
  41     """Something failed while attempting to execute a primitive."""
  42
  43
  44 # Quiet the debug logging
  45 logging.getLogger('websockets.protocol').setLevel(logging.INFO)
  46 logging.getLogger('juju.client.connection').setLevel(logging.WARN)
  47 logging.getLogger('juju.model').setLevel(logging.WARN)
  48 logging.getLogger('juju.machine').setLevel(logging.WARN)
  49
  50
  51 class VCAMonitor(ModelObserver):
  52     """Monitor state changes within the Juju Model."""
  53     log = None
  54     ns_name = None
  55     applications = {}
  56
  57     def __init__(self, ns_name):
  58         self.log = logging.getLogger(__name__)
  59
  60         self.ns_name = ns_name
  61
  62     def AddApplication(self, application_name, callback, *callback_args):
  63         if application_name not in self.applications:
  64             self.applications[application_name] = {
  65                 'callback': callback,
  66                 'callback_args': callback_args
  67             }
  68
  69     def RemoveApplication(self, application_name):
  70         if application_name in self.applications:
  71             del self.applications[application_name]
  72
  73     async def on_change(self, delta, old, new, model):
  74         """React to changes in the Juju model."""
  75
  76         if delta.entity == "unit":
  77             # Ignore change events from other applications
  78             if delta.data['application'] not in self.applications.keys():
  79                 return
  80
  81             try:
  82
  83                 application_name = delta.data['application']
  84
  85                 callback = self.applications[application_name]['callback']
  86                 callback_args = self.applications[application_name]['callback_args']
  87
  88                 if old and new:
  89                     old_status = old.workload_status
  90                     new_status = new.workload_status
  91
  92                     if old_status == new_status:
  93                         """The workload status may fluctuate around certain events,
  94                         so wait until the status has stabilized before triggering
  95                         the callback."""
  96                         if callback:
  97                             callback(
  98                                 self.ns_name,
  99                                 delta.data['application'],
 100                                 new_status,
 101                                 new.workload_status_message,
 102                                 *callback_args)
 103
 104                 if old and not new:
 105                     # This is a charm being removed
 106                     if callback:
 107                         callback(
 108                             self.ns_name,
 109                             delta.data['application'],
 110                             "removed",
 111                             "",
 112                             *callback_args)
 113             except Exception as e:
 114                 self.log.debug("[1] notify_callback exception {}".format(e))
 115         elif delta.entity == "action":
 116             # TODO: Decide how we want to notify the user of actions
 117
 118             # uuid = delta.data['id']     # The Action's unique id
 119             # msg = delta.data['message'] # The output of the action
 120             #
 121             # if delta.data['status'] == "pending":
 122             #     # The action is queued
 123             #     pass
 124             # elif delta.data['status'] == "completed""
 125             #     # The action was successful
 126             #     pass
 127             # elif delta.data['status'] == "failed":
 128             #     # The action failed.
 129             #     pass
 130
 131             pass
 132
 133 ########
 134 # TODO
 135 #
 136 # Create unique models per network service
 137 # Document all public functions
 138
 139
 140 class N2VC:
 141
 142     # Juju API
 143     api = None
 144     log = None
 145     controller = None
 146     connecting = False
 147     authenticated = False
 148
 149     models = {}
 150     default_model = None
 151
 152     # Model Observers
 153     monitors = {}
 154
 155     # VCA config
 156     hostname = ""
 157     port = 17070
 158     username = ""
 159     secret = ""
 160
 161     def __init__(self,
 162                  log=None,
 163                  server='127.0.0.1',
 164                  port=17070,
 165                  user='admin',
 166                  secret=None,
 167                  artifacts=None
 168                  ):
 169         """Initialize N2VC
 170
 171         :param vcaconfig dict A dictionary containing the VCA configuration
 172
 173         :param artifacts str The directory where charms required by a vnfd are
 174             stored.
 175
 176         :Example:
 177         n2vc = N2VC(vcaconfig={
 178             'secret': 'MzI3MDJhOTYxYmM0YzRjNTJiYmY1Yzdm',
 179             'user': 'admin',
 180             'ip-address': '10.44.127.137',
 181             'port': 17070,
 182             'artifacts': '/path/to/charms'
 183         })
 184
 185         """
 186
 187         if log:
 188             self.log = log
 189         else:
 190             self.log = logging.getLogger(__name__)
 191
 192         # Quiet websocket traffic
 193         logging.getLogger('websockets.protocol').setLevel(logging.INFO)
 194         logging.getLogger('juju.client.connection').setLevel(logging.WARN)
 195         logging.getLogger('model').setLevel(logging.WARN)
 196         # logging.getLogger('websockets.protocol').setLevel(logging.DEBUG)
 197
 198         self.log.debug('JujuApi: instantiated')
 199
 200         self.server = server
 201         self.port = port
 202
 203         self.secret = secret
 204         if user.startswith('user-'):
 205             self.user = user
 206         else:
 207             self.user = 'user-{}'.format(user)
 208
 209         self.endpoint = '%s:%d' % (server, int(port))
 210
 211         self.artifacts = artifacts
 212
 213     def __del__(self):
 214         """Close any open connections."""
 215         yield self.logout()
 216
 217     def notify_callback(self, model_name, application_name, status, message, callback=None, *callback_args):
 218         try:
 219             if callback:
 220                 callback(model_name, application_name, status, message, *callback_args)
 221         except Exception as e:
 222             self.log.error("[0] notify_callback exception {}".format(e))
 223             raise e
 224         return True
 225
 226     # Public methods
 227     async def CreateNetworkService(self, nsd):
 228         """Create a new model to encapsulate this network service.
 229
 230         Create a new model in the Juju controller to encapsulate the
 231         charms associated with a network service.
 232
 233         You can pass either the nsd record or the id of the network
 234         service, but this method will fail without one of them.
 235         """
 236         if not self.authenticated:
 237             await self.login()
 238
 239         # Ideally, we will create a unique model per network service.
 240         # This change will require all components, i.e., LCM and SO, to use
 241         # N2VC for 100% compatibility. If we adopt unique models for the LCM,
 242         # services deployed via LCM would't be manageable via SO and vice versa
 243
 244         return self.default_model
 245
 246     async def DeployCharms(self, model_name, application_name, vnfd, charm_path, params={}, machine_spec={}, callback=None, *callback_args):
 247         """Deploy one or more charms associated with a VNF.
 248
 249         Deploy the charm(s) referenced in a VNF Descriptor.
 250
 251         :param str model_name: The name of the network service.
 252         :param str application_name: The name of the application
 253         :param dict vnfd: The name of the application
 254         :param str charm_path: The path to the Juju charm
 255         :param dict params: A dictionary of runtime parameters
 256           Examples::
 257           {
 258             'rw_mgmt_ip': '1.2.3.4',
 259             # Pass the initial-config-primitives section of the vnf or vdu
 260             'initial-config-primitives': {...}
 261           }
 262         :param dict machine_spec: A dictionary describing the machine to install to
 263           Examples::
 264           {
 265             'hostname': '1.2.3.4',
 266             'username': 'ubuntu',
 267           }
 268         :param obj callback: A callback function to receive status changes.
 269         :param tuple callback_args: A list of arguments to be passed to the callback
 270         """
 271
 272         ########################################################
 273         # Verify the path to the charm exists and is readable. #
 274         ########################################################
 275         if not os.path.exists(charm_path):
 276             self.log.debug("Charm path doesn't exist: {}".format(charm_path))
 277             self.notify_callback(model_name, application_name, "failed", callback, *callback_args)
 278             raise JujuCharmNotFound("No artifacts configured.")
 279
 280         ################################
 281         # Login to the Juju controller #
 282         ################################
 283         if not self.authenticated:
 284             self.log.debug("Authenticating with Juju")
 285             await self.login()
 286
 287         ##########################################
 288         # Get the model for this network service #
 289         ##########################################
 290         # TODO: In a point release, we will use a model per deployed network
 291         # service. In the meantime, we will always use the 'default' model.
 292         model_name = 'default'
 293         model = await self.get_model(model_name)
 294
 295         ########################################
 296         # Verify the application doesn't exist #
 297         ########################################
 298         app = await self.get_application(model, application_name)
 299         if app:
 300             raise JujuApplicationExists("Can't deploy application \"{}\" to model \"{}\" because it already exists.".format(application_name, model_name))
 301
 302         ################################################################
 303         # Register this application with the model-level event monitor #
 304         ################################################################
 305         if callback:
 306             self.monitors[model_name].AddApplication(
 307                 application_name,
 308                 callback,
 309                 *callback_args
 310             )
 311
 312         ########################################################
 313         # Check for specific machine placement (native charms) #
 314         ########################################################
 315         to = ""
 316         if machine_spec.keys():
 317             # TODO: This needs to be tested.
 318             # if all(k in machine_spec for k in ['hostname', 'username']):
 319             #     # Enlist the existing machine in Juju
 320             #     machine = await self.model.add_machine(spec='ssh:%@%'.format(
 321             #         specs['host'],
 322             #         specs['user'],
 323             #     ))
 324             #     to = machine.id
 325             pass
 326
 327         #######################################
 328         # Get the initial charm configuration #
 329         #######################################
 330
 331         rw_mgmt_ip = None
 332         if 'rw_mgmt_ip' in params:
 333             rw_mgmt_ip = params['rw_mgmt_ip']
 334
 335         initial_config = self._get_config_from_dict(
 336             params['initial-config-primitive'],
 337             {'<rw_mgmt_ip>': rw_mgmt_ip}
 338         )
 339
 340         self.log.debug("JujuApi: Deploying charm ({}) from {}".format(
 341             application_name,
 342             charm_path,
 343             to=to,
 344         ))
 345
 346         ########################################################
 347         # Deploy the charm and apply the initial configuration #
 348         ########################################################
 349         app = await model.deploy(
 350             # We expect charm_path to be either the path to the charm on disk
 351             # or in the format of cs:series/name
 352             charm_path,
 353             # This is the formatted, unique name for this charm
 354             application_name=application_name,
 355             # Proxy charms should use the current LTS. This will need to be
 356             # changed for native charms.
 357             series='xenial',
 358             # Apply the initial 'config' primitive during deployment
 359             config=initial_config,
 360             # TBD: Where to deploy the charm to.
 361             to=None,
 362         )
 363
 364         # #######################################
 365         # # Execute initial config primitive(s) #
 366         # #######################################
 367         primitives = {}
 368
 369         # Build a sequential list of the primitives to execute
 370         for primitive in params['initial-config-primitive']:
 371             try:
 372                 if primitive['name'] == 'config':
 373                     # This is applied when the Application is deployed
 374                     pass
 375                 else:
 376                     seq = primitive['seq']
 377
 378                     params = {}
 379                     if 'parameter' in primitive:
 380                         params = primitive['parameter']
 381
 382                     primitives[seq] = {
 383                         'name': primitive['name'],
 384                         'parameters': self._map_primitive_parameters(
 385                             params,
 386                             {'<rw_mgmt_ip>': rw_mgmt_ip}
 387                         ),
 388                     }
 389
 390                     for primitive in sorted(primitives):
 391                         await self.ExecutePrimitive(
 392                             model_name,
 393                             application_name,
 394                             primitives[primitive]['name'],
 395                             callback,
 396                             callback_args,
 397                             **primitives[primitive]['parameters'],
 398                         )
 399             except N2VCPrimitiveExecutionFailed as e:
 400                 self.log.debug(
 401                     "[N2VC] Exception executing primitive: {}".format(e)
 402                 )
 403                 raise
 404
 405     async def ExecutePrimitive(self, model_name, application_name, primitive, callback, *callback_args, **params):
 406         """Execute a primitive of a charm for Day 1 or Day 2 configuration.
 407
 408         Execute a primitive defined in the VNF descriptor.
 409
 410         :param str model_name: The name of the network service.
 411         :param str application_name: The name of the application
 412         :param str primitive: The name of the primitive to execute.
 413         :param obj callback: A callback function to receive status changes.
 414         :param tuple callback_args: A list of arguments to be passed to the callback function.
 415         :param dict params: A dictionary of key=value pairs representing the primitive's parameters
 416           Examples::
 417           {
 418             'rw_mgmt_ip': '1.2.3.4',
 419             # Pass the initial-config-primitives section of the vnf or vdu
 420             'initial-config-primitives': {...}
 421           }
 422         """
 423         uuid = None
 424         try:
 425             if not self.authenticated:
 426                 await self.login()
 427
 428             # FIXME: This is hard-coded until model-per-ns is added
 429             model_name = 'default'
 430
 431             model = await self.controller.get_model(model_name)
 432
 433             if primitive == 'config':
 434                 # config is special, and expecting params to be a dictionary
 435                 self.log.debug("Setting charm configuration for {}".format(application_name))
 436                 self.log.debug(params['params'])
 437                 await self.set_config(model, application_name, params['params'])
 438             else:
 439                 app = await self.get_application(model, application_name)
 440                 if app:
 441                     # Run against the first (and probably only) unit in the app
 442                     unit = app.units[0]
 443                     if unit:
 444                         self.log.debug("Executing primitive {}".format(primitive))
 445                         action = await unit.run_action(primitive, **params)
 446                         uuid = action.id
 447                 await model.disconnect()
 448         except Exception as e:
 449             self.log.debug("Caught exception while executing primitive: {}".format(e))
 450             raise N2VCPrimitiveExecutionFailed(e)
 451         return uuid
 452
 453     async def RemoveCharms(self, model_name, application_name, callback=None, *callback_args):
 454         """Remove a charm from the VCA.
 455
 456         Remove a charm referenced in a VNF Descriptor.
 457
 458         :param str model_name: The name of the network service.
 459         :param str application_name: The name of the application
 460         :param obj callback: A callback function to receive status changes.
 461         :param tuple callback_args: A list of arguments to be passed to the callback function.
 462         """
 463         try:
 464             if not self.authenticated:
 465                 await self.login()
 466
 467             model = await self.get_model(model_name)
 468             app = await self.get_application(model, application_name)
 469             if app:
 470                 # Remove this application from event monitoring
 471                 self.monitors[model_name].RemoveApplication(application_name)
 472
 473                 # self.notify_callback(model_name, application_name, "removing", callback, *callback_args)
 474                 self.log.debug("Removing the application {}".format(application_name))
 475                 await app.remove()
 476
 477                 # Notify the callback that this charm has been removed.
 478                 self.notify_callback(model_name, application_name, "removed", callback, *callback_args)
 479
 480         except Exception as e:
 481             print("Caught exception: {}".format(e))
 482             self.log.debug(e)
 483             raise e
 484
 485     async def DestroyNetworkService(self, nsd):
 486         raise NotImplementedError()
 487
 488     async def GetMetrics(self, model_name, application_name):
 489         """Get the metrics collected by the VCA.
 490
 491         :param model_name The name of the model
 492         :param application_name The name of the application
 493         """
 494         metrics = {}
 495         model = await self.get_model(model_name)
 496         app = await self.get_application(model, application_name)
 497         if app:
 498             metrics = await app.get_metrics()
 499
 500         return metrics
 501
 502     # Non-public methods
 503     async def add_relation(self, a, b, via=None):
 504         """
 505         Add a relation between two application endpoints.
 506
 507         :param a An application endpoint
 508         :param b An application endpoint
 509         :param via The egress subnet(s) for outbound traffic, e.g.,
 510             (192.168.0.0/16,10.0.0.0/8)
 511         """
 512         if not self.authenticated:
 513             await self.login()
 514
 515         m = await self.get_model()
 516         try:
 517             m.add_relation(a, b, via)
 518         finally:
 519             await m.disconnect()
 520
 521     # async def apply_config(self, config, application):
 522     #     """Apply a configuration to the application."""
 523     #     print("JujuApi: Applying configuration to {}.".format(
 524     #         application
 525     #     ))
 526     #     return await self.set_config(application=application, config=config)
 527
 528     def _get_config_from_dict(self, config_primitive, values):
 529         """Transform the yang config primitive to dict.
 530
 531         Expected result:
 532
 533             config = {
 534                 'config':
 535             }
 536         """
 537         config = {}
 538         for primitive in config_primitive:
 539             if primitive['name'] == 'config':
 540                 # config = self._map_primitive_parameters()
 541                 for parameter in primitive['parameter']:
 542                     param = str(parameter['name'])
 543                     if parameter['value'] == "<rw_mgmt_ip>":
 544                         config[param] = str(values[parameter['value']])
 545                     else:
 546                         config[param] = str(parameter['value'])
 547
 548         return config
 549
 550     def _map_primitive_parameters(self, parameters, values):
 551         params = {}
 552         for parameter in parameters:
 553             param = str(parameter['name'])
 554             if parameter['value'] == "<rw_mgmt_ip>":
 555                 params[param] = str(values[parameter['value']])
 556             else:
 557                 """
 558                 The Juju API uses strictly typed data-types, so we must make
 559                 sure the parameters from the VNFD match the appropriate type.
 560
 561                 The honus will still be on the operator, to make sure the
 562                 data-type in the VNFD matches the one in the charm. N2VC will
 563                 raise N2VCPrimitiveExecutionFailed when there is a mismatch.
 564
 565                 There are three data types supported by the YANG model:
 566                 # - STRING
 567                 # - INTEGER
 568                 # - BOOLEAN
 569
 570                 Each parameter will look like this:
 571                 {
 572                     'seq': '3',
 573                     'name': 'testint',
 574                     'parameter': [
 575                         {
 576                             'name': 'interval',
 577                             'data-type': 'INTEGER',
 578                             'value': 20
 579                         }
 580                     ]
 581                 }
 582                 """
 583
 584                 if 'value' in parameter:
 585                     # String is the default format
 586                     val = str(parameter['value'])
 587
 588                     # If the data-type is explicitly set, cast to that type.
 589                     if 'data-type' in parameter:
 590                         dt = parameter['data-type'].upper()
 591                         if dt == "INTEGER":
 592                             val = int(val)
 593
 594                         elif dt == "BOOLEAN":
 595                             if val in ['true', 'false', '0', '1']:
 596                                 val = True
 597                             else:
 598                                 val = False
 599
 600                     params[param] = val
 601         return params
 602
 603     def _get_config_from_yang(self, config_primitive, values):
 604         """Transform the yang config primitive to dict."""
 605         config = {}
 606         for primitive in config_primitive.values():
 607             if primitive['name'] == 'config':
 608                 for parameter in primitive['parameter'].values():
 609                     param = str(parameter['name'])
 610                     if parameter['value'] == "<rw_mgmt_ip>":
 611                         config[param] = str(values[parameter['value']])
 612                     else:
 613                         config[param] = str(parameter['value'])
 614
 615         return config
 616
 617     def FormatApplicationName(self, *args):
 618         """
 619         Generate a Juju-compatible Application name
 620
 621         :param args tuple: Positional arguments to be used to construct the
 622         application name.
 623
 624         Limitations::
 625         - Only accepts characters a-z and non-consequitive dashes (-)
 626         - Application name should not exceed 50 characters
 627
 628         Examples::
 629
 630             FormatApplicationName("ping_pong_ns", "ping_vnf", "a")
 631         """
 632
 633         appname = ""
 634         for c in "-".join(list(args)):
 635             if c.isdigit():
 636                 c = chr(97 + int(c))
 637             elif not c.isalpha():
 638                 c = "-"
 639             appname += c
 640         return re.sub('\-+', '-', appname.lower())
 641
 642
 643     # def format_application_name(self, nsd_name, vnfr_name, member_vnf_index=0):
 644     #     """Format the name of the application
 645     #
 646     #     Limitations:
 647     #     - Only accepts characters a-z and non-consequitive dashes (-)
 648     #     - Application name should not exceed 50 characters
 649     #     """
 650     #     name = "{}-{}-{}".format(nsd_name, vnfr_name, member_vnf_index)
 651     #     new_name = ''
 652     #     for c in name:
 653     #         if c.isdigit():
 654     #             c = chr(97 + int(c))
 655     #         elif not c.isalpha():
 656     #             c = "-"
 657     #         new_name += c
 658     #     return re.sub('\-+', '-', new_name.lower())
 659
 660     def format_model_name(self, name):
 661         """Format the name of model.
 662
 663         Model names may only contain lowercase letters, digits and hyphens
 664         """
 665
 666         return name.replace('_', '-').lower()
 667
 668     async def get_application(self, model, application):
 669         """Get the deployed application."""
 670         if not self.authenticated:
 671             await self.login()
 672
 673         app = None
 674         if application and model:
 675             if model.applications:
 676                 if application in model.applications:
 677                     app = model.applications[application]
 678
 679         return app
 680
 681     async def get_model(self, model_name='default'):
 682         """Get a model from the Juju Controller.
 683
 684         Note: Model objects returned must call disconnected() before it goes
 685         out of scope."""
 686         if not self.authenticated:
 687             await self.login()
 688
 689         if model_name not in self.models:
 690             print("connecting to model {}".format(model_name))
 691             self.models[model_name] = await self.controller.get_model(model_name)
 692
 693             # Create an observer for this model
 694             self.monitors[model_name] = VCAMonitor(model_name)
 695             self.models[model_name].add_observer(self.monitors[model_name])
 696
 697         return self.models[model_name]
 698
 699     async def login(self):
 700         """Login to the Juju controller."""
 701
 702         if self.authenticated:
 703             return
 704
 705         self.connecting = True
 706
 707         self.log.debug("JujuApi: Logging into controller")
 708
 709         cacert = None
 710         self.controller = Controller()
 711
 712         if self.secret:
 713             self.log.debug("Connecting to controller... ws://{}:{} as {}/{}".format(self.endpoint, self.port, self.user, self.secret))
 714             await self.controller.connect(
 715                 endpoint=self.endpoint,
 716                 username=self.user,
 717                 password=self.secret,
 718                 cacert=cacert,
 719             )
 720         else:
 721             # current_controller no longer exists
 722             # self.log.debug("Connecting to current controller...")
 723             # await self.controller.connect_current()
 724             # await self.controller.connect(
 725             #     endpoint=self.endpoint,
 726             #     username=self.user,
 727             #     cacert=cacert,
 728             # )
 729             self.log.fatal("VCA credentials not configured.")
 730
 731         self.authenticated = True
 732         self.log.debug("JujuApi: Logged into controller")
 733
 734         # self.default_model = await self.controller.get_model("default")
 735
 736     async def logout(self):
 737         """Logout of the Juju controller."""
 738         if not self.authenticated:
 739             return
 740
 741         try:
 742             if self.default_model:
 743                 self.log.debug("Disconnecting model {}".format(self.default_model))
 744                 await self.default_model.disconnect()
 745                 self.default_model = None
 746
 747             for model in self.models:
 748                 await self.models[model].disconnect()
 749
 750             if self.controller:
 751                 self.log.debug("Disconnecting controller {}".format(self.controller))
 752                 await self.controller.disconnect()
 753                 # self.controller = None
 754
 755             self.authenticated = False
 756         except Exception as e:
 757             self.log.fail("Fatal error logging out of Juju Controller: {}".format(e))
 758             raise e
 759
 760
 761     # async def remove_application(self, name):
 762     #     """Remove the application."""
 763     #     if not self.authenticated:
 764     #         await self.login()
 765     #
 766     #     app = await self.get_application(name)
 767     #     if app:
 768     #         self.log.debug("JujuApi: Destroying application {}".format(
 769     #             name,
 770     #         ))
 771     #
 772     #         await app.destroy()
 773
 774     async def remove_relation(self, a, b):
 775         """
 776         Remove a relation between two application endpoints
 777
 778         :param a An application endpoint
 779         :param b An application endpoint
 780         """
 781         if not self.authenticated:
 782             await self.login()
 783
 784         m = await self.get_model()
 785         try:
 786             m.remove_relation(a, b)
 787         finally:
 788             await m.disconnect()
 789
 790     async def resolve_error(self, application=None):
 791         """Resolve units in error state."""
 792         if not self.authenticated:
 793             await self.login()
 794
 795         app = await self.get_application(self.default_model, application)
 796         if app:
 797             self.log.debug("JujuApi: Resolving errors for application {}".format(
 798                 application,
 799             ))
 800
 801             for unit in app.units:
 802                 app.resolved(retry=True)
 803
 804     async def run_action(self, application, action_name, **params):
 805         """Execute an action and return an Action object."""
 806         if not self.authenticated:
 807             await self.login()
 808         result = {
 809             'status': '',
 810             'action': {
 811                 'tag': None,
 812                 'results': None,
 813             }
 814         }
 815         app = await self.get_application(self.default_model, application)
 816         if app:
 817             # We currently only have one unit per application
 818             # so use the first unit available.
 819             unit = app.units[0]
 820
 821             self.log.debug("JujuApi: Running Action {} against Application {}".format(
 822                 action_name,
 823                 application,
 824             ))
 825
 826             action = await unit.run_action(action_name, **params)
 827
 828             # Wait for the action to complete
 829             await action.wait()
 830
 831             result['status'] = action.status
 832             result['action']['tag'] = action.data['id']
 833             result['action']['results'] = action.results
 834
 835         return result
 836
 837     async def set_config(self, model_name, application, config):
 838         """Apply a configuration to the application."""
 839         if not self.authenticated:
 840             await self.login()
 841
 842         app = await self.get_application(model_name, application)
 843         if app:
 844             self.log.debug("JujuApi: Setting config for Application {}".format(
 845                 application,
 846             ))
 847             await app.set_config(config)
 848
 849             # Verify the config is set
 850             newconf = await app.get_config()
 851             for key in config:
 852                 if config[key] != newconf[key]['value']:
 853                     self.log.debug("JujuApi: Config not set! Key {} Value {} doesn't match {}".format(key, config[key], newconf[key]))
 854
 855     # async def set_parameter(self, parameter, value, application=None):
 856     #     """Set a config parameter for a service."""
 857     #     if not self.authenticated:
 858     #         await self.login()
 859     #
 860     #     self.log.debug("JujuApi: Setting {}={} for Application {}".format(
 861     #         parameter,
 862     #         value,
 863     #         application,
 864     #     ))
 865     #     return await self.apply_config(
 866     #         {parameter: value},
 867     #         application=application,
 868         # )
 869
 870     async def wait_for_application(self, name, timeout=300):
 871         """Wait for an application to become active."""
 872         if not self.authenticated:
 873             await self.login()
 874
 875         app = await self.get_application(self.default_model, name)
 876         if app:
 877             self.log.debug(
 878                 "JujuApi: Waiting {} seconds for Application {}".format(
 879                     timeout,
 880                     name,
 881                 )
 882             )
 883
 884             await self.default_model.block_until(
 885                 lambda: all(
 886                     unit.agent_status == 'idle'
 887                     and unit.workload_status
 888                     in ['active', 'unknown'] for unit in app.units
 889                 ),
 890                 timeout=timeout
 891             )