sfa/planetlab/plslices.py

   1 import time
   2 from types import StringTypes
   3 from collections import defaultdict
   4
   5 from sfa.util.sfatime import utcparse, datetime_to_epoch
   6 from sfa.util.sfalogging import logger
   7 from sfa.util.xrn import Xrn, get_leaf, get_authority, urn_to_hrn
   8 from sfa.rspecs.rspec import RSpec
   9 from sfa.planetlab.vlink import VLink
  10 from sfa.planetlab.topology import Topology
  11 from sfa.planetlab.plxrn import PlXrn, hrn_to_pl_slicename, xrn_to_hostname, top_auth, hash_loginbase
  12 from sfa.storage.model import SliverAllocation
  13
  14 MAXINT =  2L**31-1
  15
  16 class PlSlices:
  17
  18     rspec_to_slice_tag = {'max_rate':'net_max_rate'}
  19
  20     def __init__(self, driver):
  21         self.driver = driver
  22
  23     def get_slivers(self, xrn, node=None):
  24         hrn, type = urn_to_hrn(xrn)
  25
  26         slice_name = hrn_to_pl_slicename(hrn)
  27         # XX Should we just call PLCAPI.GetSliceTicket(slice_name) instead
  28         # of doing all of this?
  29         #return self.driver.shell.GetSliceTicket(self.auth, slice_name)
  30
  31         # from PLCAPI.GetSlivers.get_slivers()
  32         slice_fields = ['slice_id', 'name', 'instantiation', 'expires', 'person_ids', 'slice_tag_ids']
  33         slices = self.driver.shell.GetSlices(slice_name, slice_fields)
  34         # Build up list of users and slice attributes
  35         person_ids = set()
  36         all_slice_tag_ids = set()
  37         for slice in slices:
  38             person_ids.update(slice['person_ids'])
  39             all_slice_tag_ids.update(slice['slice_tag_ids'])
  40         person_ids = list(person_ids)
  41         all_slice_tag_ids = list(all_slice_tag_ids)
  42         # Get user information
  43         all_persons_list = self.driver.shell.GetPersons({'person_id':person_ids,'enabled':True}, ['person_id', 'enabled', 'key_ids'])
  44         all_persons = {}
  45         for person in all_persons_list:
  46             all_persons[person['person_id']] = person
  47
  48         # Build up list of keys
  49         key_ids = set()
  50         for person in all_persons.values():
  51             key_ids.update(person['key_ids'])
  52         key_ids = list(key_ids)
  53         # Get user account keys
  54         all_keys_list = self.driver.shell.GetKeys(key_ids, ['key_id', 'key', 'key_type'])
  55         all_keys = {}
  56         for key in all_keys_list:
  57             all_keys[key['key_id']] = key
  58         # Get slice attributes
  59         all_slice_tags_list = self.driver.shell.GetSliceTags(all_slice_tag_ids)
  60         all_slice_tags = {}
  61         for slice_tag in all_slice_tags_list:
  62             all_slice_tags[slice_tag['slice_tag_id']] = slice_tag
  63
  64         slivers = []
  65         for slice in slices:
  66             keys = []
  67             for person_id in slice['person_ids']:
  68                 if person_id in all_persons:
  69                     person = all_persons[person_id]
  70                     if not person['enabled']:
  71                         continue
  72                     for key_id in person['key_ids']:
  73                         if key_id in all_keys:
  74                             key = all_keys[key_id]
  75                             keys += [{'key_type': key['key_type'],
  76                                     'key': key['key']}]
  77             attributes = []
  78             # All (per-node and global) attributes for this slice
  79             slice_tags = []
  80             for slice_tag_id in slice['slice_tag_ids']:
  81                 if slice_tag_id in all_slice_tags:
  82                     slice_tags.append(all_slice_tags[slice_tag_id])
  83             # Per-node sliver attributes take precedence over global
  84             # slice attributes, so set them first.
  85             # Then comes nodegroup slice attributes
  86             # Followed by global slice attributes
  87             sliver_attributes = []
  88
  89             if node is not None:
  90                 for sliver_attribute in filter(lambda a: a['node_id'] == node['node_id'], slice_tags):
  91                     sliver_attributes.append(sliver_attribute['tagname'])
  92                     attributes.append({'tagname': sliver_attribute['tagname'],
  93                                     'value': sliver_attribute['value']})
  94
  95             # set nodegroup slice attributes
  96             for slice_tag in filter(lambda a: a['nodegroup_id'] in node['nodegroup_ids'], slice_tags):
  97                 # Do not set any nodegroup slice attributes for
  98                 # which there is at least one sliver attribute
  99                 # already set.
 100                 if slice_tag not in slice_tags:
 101                     attributes.append({'tagname': slice_tag['tagname'],
 102                         'value': slice_tag['value']})
 103
 104             for slice_tag in filter(lambda a: a['node_id'] is None, slice_tags):
 105                 # Do not set any global slice attributes for
 106                 # which there is at least one sliver attribute
 107                 # already set.
 108                 if slice_tag['tagname'] not in sliver_attributes:
 109                     attributes.append({'tagname': slice_tag['tagname'],
 110                                    'value': slice_tag['value']})
 111
 112             # XXX Sanity check; though technically this should be a system invariant
 113             # checked with an assertion
 114             if slice['expires'] > MAXINT:  slice['expires']= MAXINT
 115
 116             slivers.append({
 117                 'hrn': hrn,
 118                 'name': slice['name'],
 119                 'slice_id': slice['slice_id'],
 120                 'instantiation': slice['instantiation'],
 121                 'expires': slice['expires'],
 122                 'keys': keys,
 123                 'attributes': attributes
 124             })
 125
 126         return slivers
 127
 128
 129     def get_sfa_peer(self, xrn):
 130         hrn, type = urn_to_hrn(xrn)
 131
 132         # return the authority for this hrn or None if we are the authority
 133         sfa_peer = None
 134         slice_authority = get_authority(hrn)
 135         site_authority = get_authority(slice_authority)
 136
 137         if site_authority != self.driver.hrn:
 138             sfa_peer = site_authority
 139
 140         return sfa_peer
 141
 142     def verify_slice_leases(self, slice, rspec_requested_leases):
 143
 144         leases = self.driver.shell.GetLeases({'name':slice['name'], 'clip':int(time.time())}, ['lease_id','name', 'hostname', 't_from', 't_until'])
 145         grain = self.driver.shell.GetLeaseGranularity()
 146
 147         requested_leases = []
 148         for lease in rspec_requested_leases:
 149              requested_lease = {}
 150              slice_hrn, _ = urn_to_hrn(lease['slice_id'])
 151
 152              top_auth_hrn = top_auth(slice_hrn)
 153              site_hrn = '.'.join(slice_hrn.split('.')[:-1])
 154              slice_part = slice_hrn.split('.')[-1]
 155              if top_auth_hrn == self.driver.hrn:
 156                  login_base = slice_hrn.split('.')[-2][:12]
 157              else:
 158                  login_base = hash_loginbase(site_hrn)
 159
 160              slice_name = '_'.join([login_base, slice_part])
 161
 162              if slice_name != slice['name']:
 163                  continue
 164              elif Xrn(lease['component_id']).get_authority_urn().split(':')[0] != self.driver.hrn:
 165                  continue
 166
 167              hostname = xrn_to_hostname(lease['component_id'])
 168              # fill the requested node with nitos ids
 169              requested_lease['name'] = slice['name']
 170              requested_lease['hostname'] = hostname
 171              requested_lease['t_from'] = int(lease['start_time'])
 172              requested_lease['t_until'] = int(lease['duration']) * grain + int(lease['start_time'])
 173              requested_leases.append(requested_lease)
 174
 175
 176
 177         # prepare actual slice leases by lease_id
 178         leases_by_id = {}
 179         for lease in leases:
 180              leases_by_id[lease['lease_id']] = {'name': lease['name'], 'hostname': lease['hostname'], \
 181                                                 't_from': lease['t_from'], 't_until': lease['t_until']}
 182
 183         added_leases = []
 184         kept_leases_id = []
 185         deleted_leases_id = []
 186         for lease_id in leases_by_id:
 187              if leases_by_id[lease_id] not in requested_leases:
 188                  deleted_leases_id.append(lease_id)
 189              else:
 190                  kept_leases_id.append(lease_id)
 191                  requested_leases.remove(leases_by_id[lease_id])
 192         added_leases = requested_leases
 193
 194
 195         try:
 196             self.driver.shell.DeleteLeases(deleted_leases_id)
 197             for lease in added_leases:
 198                 self.driver.shell.AddLeases(lease['hostname'], slice['name'], lease['t_from'], lease['t_until'])
 199
 200         except:
 201             logger.log_exc('Failed to add/remove slice leases')
 202
 203         return leases
 204
 205
 206     def verify_slice_nodes(self, slice_urn, slice, rspec_nodes):
 207
 208         slivers = {}
 209         for node in rspec_nodes:
 210             hostname = node.get('component_name')
 211             client_id = node.get('client_id')
 212             component_id = node.get('component_id').strip()
 213             if hostname:
 214                 hostname = hostname.strip()
 215             elif component_id:
 216                 hostname = xrn_to_hostname(component_id)
 217             if hostname:
 218                 slivers[hostname] = {'client_id': client_id, 'component_id': component_id}
 219
 220         nodes = self.driver.shell.GetNodes(slice['node_ids'], ['node_id', 'hostname', 'interface_ids'])
 221         current_slivers = [node['hostname'] for node in nodes]
 222
 223         # remove nodes not in rspec
 224         deleted_nodes = list(set(current_slivers).difference(slivers.keys()))
 225
 226         # add nodes from rspec
 227         added_nodes = list(set(slivers.keys()).difference(current_slivers))
 228
 229         try:
 230             self.driver.shell.AddSliceToNodes(slice['name'], added_nodes)
 231             self.driver.shell.DeleteSliceFromNodes(slice['name'], deleted_nodes)
 232
 233         except:
 234             logger.log_exc('Failed to add/remove slice from nodes')
 235
 236         slices = self.driver.shell.GetSlices(slice['name'], ['node_ids'])
 237         resulting_nodes = self.driver.shell.GetNodes(slices[0]['node_ids'])
 238
 239         # update sliver allocations
 240         for node in resulting_nodes:
 241             client_id = slivers[node['hostname']]['client_id']
 242             component_id = slivers[node['hostname']]['component_id']
 243             sliver_hrn = '%s.%s-%s' % (self.driver.hrn, slice['slice_id'], node['node_id'])
 244             sliver_id = Xrn(sliver_hrn, type='sliver').urn
 245             record = SliverAllocation(sliver_id=sliver_id, client_id=client_id,
 246                                       component_id=component_id,
 247                                       slice_urn = slice_urn,
 248                                       allocation_state='geni_allocated')
 249             record.sync(self.driver.api.dbsession())
 250         return resulting_nodes
 251
 252     def free_egre_key(self):
 253         used = set()
 254         for tag in self.driver.shell.GetSliceTags({'tagname': 'egre_key'}):
 255                 used.add(int(tag['value']))
 256
 257         for i in range(1, 256):
 258             if i not in used:
 259                 key = i
 260                 break
 261         else:
 262             raise KeyError("No more EGRE keys available")
 263
 264         return str(key)
 265
 266     def verify_slice_links(self, slice, requested_links, nodes):
 267
 268         if not requested_links:
 269             return
 270
 271         # exit if links are not supported here
 272         topology = Topology()
 273         if not topology:
 274             return
 275
 276         # build dict of nodes
 277         nodes_dict = {}
 278         interface_ids = []
 279         for node in nodes:
 280             nodes_dict[node['node_id']] = node
 281             interface_ids.extend(node['interface_ids'])
 282         # build dict of interfaces
 283         interfaces = self.driver.shell.GetInterfaces(interface_ids)
 284         interfaces_dict = {}
 285         for interface in interfaces:
 286             interfaces_dict[interface['interface_id']] = interface
 287
 288         slice_tags = []
 289
 290         # set egre key
 291         slice_tags.append({'name': 'egre_key', 'value': self.free_egre_key()})
 292
 293         # set netns
 294         slice_tags.append({'name': 'netns', 'value': '1'})
 295
 296         # set cap_net_admin
 297         # need to update the attribute string?
 298         slice_tags.append({'name': 'capabilities', 'value': 'CAP_NET_ADMIN'})
 299
 300         for link in requested_links:
 301             # get the ip address of the first node in the link
 302             ifname1 = Xrn(link['interface1']['component_id']).get_leaf()
 303
 304             if ifname1:
 305                 ifname_parts = ifname1.split(':')
 306                 node_raw = ifname_parts[0]
 307                 device = None
 308                 if len(ifname_parts) > 1:
 309                     device = ifname_parts[1]
 310                 node_id = int(node_raw.replace('node', ''))
 311                 node = nodes_dict[node_id]
 312                 if1 = interfaces_dict[node['interface_ids'][0]]
 313                 ipaddr = if1['ip']
 314                 topo_rspec = VLink.get_topo_rspec(link, ipaddr)
 315                 # set topo_rspec tag
 316                 slice_tags.append({'name': 'topo_rspec', 'value': str([topo_rspec]), 'node_id': node_id})
 317                 # set vini_topo tag
 318                 slice_tags.append({'name': 'vini_topo', 'value': 'manual', 'node_id': node_id})
 319                 #self.driver.shell.AddSliceTag(slice['name'], 'topo_rspec', str([topo_rspec]), node_id)
 320
 321         self.verify_slice_attributes(slice, slice_tags, {'append': True}, admin=True)
 322
 323
 324
 325     def verify_site(self, slice_xrn, slice_record=None, sfa_peer=None, options=None):
 326         if slice_record is None: slice_record={}
 327         if options is None: options={}
 328         (slice_hrn, type) = urn_to_hrn(slice_xrn)
 329         top_auth_hrn = top_auth(slice_hrn)
 330         site_hrn = '.'.join(slice_hrn.split('.')[:-1])
 331         if top_auth_hrn == self.driver.hrn:
 332             login_base = slice_hrn.split('.')[-2][:12]
 333         else:
 334             login_base = hash_loginbase(site_hrn)
 335         #plxrn = PlXrn(xrn=slice_xrn)
 336         #slice_hrn = plxrn.get_hrn()
 337         #type = plxrn.get_type()
 338         #site_hrn = plxrn.get_authority_hrn()
 339         #authority_name = plxrn.pl_authname()
 340         #slicename = plxrn.pl_slicename()
 341         #login_base = plxrn.pl_login_base()
 342
 343         sites = self.driver.shell.GetSites({'peer_id': None},['site_id','name','abbreviated_name','login_base','hrn'])
 344
 345         # filter sites by hrn
 346         site_exists = [site for site in sites if site['hrn'] == site_hrn]
 347
 348         if not site_exists:
 349             # create new site record
 350             site = {'name': 'sfa:%s' % site_hrn,
 351                     'abbreviated_name': site_hrn,
 352                     'login_base': login_base,
 353                     'max_slices': 100,
 354                     'max_slivers': 1000,
 355                     'enabled': True,
 356                     'peer_site_id': None}
 357
 358             site['site_id'] = self.driver.shell.AddSite(site)
 359             # Set site HRN
 360             self.driver.shell.SetSiteHrn(int(site['site_id']), site_hrn)
 361             # Tag this as created through SFA
 362             self.driver.shell.SetSiteSfaCreated(int(site['site_id']), 'True')
 363             # exempt federated sites from monitor policies
 364             self.driver.shell.AddSiteTag(int(site['site_id']), 'exempt_site_until', "20200101")
 365
 366         else:
 367             site =  site_exists[0]
 368
 369         return site
 370
 371
 372     def verify_slice(self, slice_hrn, slice_record, sfa_peer, expiration, options=None):
 373         if options is None: options={}
 374         top_auth_hrn = top_auth(slice_hrn)
 375         site_hrn = '.'.join(slice_hrn.split('.')[:-1])
 376         slice_part = slice_hrn.split('.')[-1]
 377         if top_auth_hrn == self.driver.hrn:
 378             login_base = slice_hrn.split('.')[-2][:12]
 379         else:
 380             login_base = hash_loginbase(site_hrn)
 381         slice_name = '_'.join([login_base, slice_part])
 382         #plxrn = PlXrn(xrn=slice_hrn)
 383         #slice_hrn = plxrn.get_hrn()
 384         #type = plxrn.get_type()
 385         #site_hrn = plxrn.get_authority_hrn()
 386         #authority_name = plxrn.pl_authname()
 387         #slicename = plxrn.pl_slicename()
 388         #login_base = plxrn.pl_login_base()
 389
 390         slices = self.driver.shell.GetSlices({'peer_id': None},['slice_id','name','hrn'])
 391         # Filter slices by HRN
 392         slice_exists = [slice for slice in slices if slice['hrn'] == slice_hrn]
 393         expires = int(datetime_to_epoch(utcparse(expiration)))
 394         if not slice_exists:
 395             if slice_record:
 396                 url = slice_record.get('url', slice_hrn)
 397                 description = slice_record.get('description', slice_hrn)
 398             else:
 399                 url = slice_hrn
 400                 description = slice_hrn
 401             slice = {'name': slice_name,
 402                      'url': url,
 403                      'description': description}
 404             # add the slice
 405             slice['slice_id'] = self.driver.shell.AddSlice(slice)
 406             # set the slice HRN
 407             self.driver.shell.SetSliceHrn(int(slice['slice_id']), slice_hrn)
 408             # Tag this as created through SFA
 409             self.driver.shell.SetSliceSfaCreated(int(slice['slice_id']), 'True')
 410             # set the expiration
 411             self.driver.shell.UpdateSlice(int(slice['slice_id']), {'expires': expires})
 412
 413         else:
 414             slice = slice_exists[0]
 415             #Update expiration if necessary
 416             if slice.get('expires', None) != expires:
 417                 self.driver.shell.UpdateSlice( int(slice['slice_id']), {'expires' : expires})
 418
 419         return self.driver.shell.GetSlices(int(slice['slice_id']))[0]
 420
 421
 422     def verify_persons(self, slice_hrn, slice_record, users, sfa_peer, options=None):
 423         if options is None: options={}
 424         top_auth_hrn = top_auth(slice_hrn)
 425         site_hrn = '.'.join(slice_hrn.split('.')[:-1])
 426         slice_part = slice_hrn.split('.')[-1]
 427         users_by_hrn = {}
 428         for user in users:
 429            user['hrn'], _ = urn_to_hrn(user['urn'])
 430            users_by_hrn[user['hrn']] = user
 431
 432         if top_auth_hrn == self.driver.hrn:
 433             login_base = slice_hrn.split('.')[-2][:12]
 434         else:
 435             login_base = hash_loginbase(site_hrn)
 436
 437         slice_name = '_'.join([login_base, slice_part])
 438
 439         persons = self.driver.shell.GetPersons({'peer_id': None},['person_id','email','hrn'])
 440         sites = self.driver.shell.GetSites({'peer_id': None}, ['node_ids', 'site_id', 'name', 'person_ids', 'slice_ids', 'login_base', 'hrn'])
 441         site = [site for site in sites if site['hrn'] == site_hrn][0]
 442         slices = self.driver.shell.GetSlices({'peer_id': None}, ['slice_id', 'node_ids', 'person_ids', 'expires', 'site_id', 'name', 'hrn'])
 443         slice = [slice for slice in slices if slice['hrn'] == slice_hrn][0]
 444         slice_persons = self.driver.shell.GetPersons({'peer_id': None, 'person_id': slice['person_ids']},['person_id','email','hrn'])
 445
 446         persons_by_hrn = {}
 447         persons_by_email = {}
 448         for person in persons:
 449            persons_by_hrn[person['hrn']] = person
 450            persons_by_email[person['email']] = person
 451         slice_persons_by_hrn = {}
 452         for slice_person in slice_persons:
 453            slice_persons_by_hrn[slice_person['hrn']] = slice_person
 454
 455         # sort persons by HRN
 456         persons_to_add = set(users_by_hrn.keys()).difference(slice_persons_by_hrn.keys())
 457         persons_to_delete = set(slice_persons_by_hrn.keys()).difference(users_by_hrn.keys())
 458         persons_to_keep = set(users_by_hrn.keys()).intersection(slice_persons_by_hrn.keys())
 459
 460
 461         persons_to_verify_keys = {}
 462
 463         # Add persons or add persons to slice
 464         for person_hrn in persons_to_add:
 465              person_email = users_by_hrn[person_hrn].get('email', "%s@geni.net"%person_hrn.split('.')[-1])
 466              if person_email and person_email in persons_by_email.keys():
 467                  # check if the user already exist in PL
 468                  person_id = persons_by_email[person_email]['person_id']
 469                  self.driver.shell.AddPersonToSlice(person_id, slice['slice_id'])
 470                  persons_to_verify_keys[person_id] = users_by_hrn[person_hrn]
 471
 472              else:
 473                  person = {
 474                            'first_name': person_hrn,
 475                            'last_name': person_hrn,
 476                            'email': users_by_hrn[person_hrn].get('email', "%s@geni.net"%person_hrn.split('.')[-1]),
 477                           }
 478
 479                  person_id = self.driver.shell.AddPerson(person)
 480                  self.driver.shell.AddRoleToPerson('user', int(person_id))
 481                  # enable the account
 482                  self.driver.shell.UpdatePerson(int(person_id), {'enabled': True})
 483                  self.driver.shell.SetPersonSfaCreated(int(person_id), 'True')
 484                  self.driver.shell.AddPersonToSite(int(person_id), site['site_id'])
 485                  self.driver.shell.AddPersonToSlice(int(person_id), slice['slice_id'])
 486                  self.driver.shell.SetPersonHrn(int(person_id), person_hrn)
 487
 488                  # Add keys
 489                  for key in users_by_hrn[person_hrn].get('keys', []):
 490                       key = {'key':key, 'key_type':'ssh'}
 491                       self.driver.shell.AddPersonKey(person_id, key)
 492
 493
 494         # Delete persons from slice
 495         for person_hrn in persons_to_delete:
 496              person_id = slice_persons_by_hrn[person_hrn].get('person_id')
 497              slice_id = slice['slice_id']
 498              self.driver.shell.DeletePersonFromSlice(person_id, slice_id)
 499
 500
 501         # Update kept persons
 502         for person_hrn in persons_to_keep:
 503              person_id = slice_persons_by_hrn[person_hrn].get('person_id')
 504              persons_to_verify_keys[person_id] = users_by_hrn[person_hrn]
 505
 506         self.verify_keys(persons_to_verify_keys, options)
 507
 508         return persons_to_add
 509
 510
 511     def verify_keys(self, persons_to_verify_keys, options=None):
 512         if options is None: options={}
 513         # we only add keys that comes from sfa to persons in PL
 514         for person_id in persons_to_verify_keys:
 515              person_sfa_keys = persons_to_verify_keys[person_id].get('keys', [])
 516              person_pl_keys = self.driver.shell.GetKeys({'person_id': int(person_id)})
 517              person_pl_keys_list = [key['key'] for key in person_pl_keys]
 518
 519              keys_to_add = set(person_sfa_keys).difference(person_pl_keys_list)
 520
 521              for key_string in keys_to_add:
 522                   key = {'key': key_string, 'key_type': 'ssh'}
 523                   self.driver.shell.AddPersonKey(int(person_id), key)
 524
 525
 526     def verify_slice_attributes(self, slice, requested_slice_attributes, options=None, admin=False):
 527         if options is None: options={}
 528         append = options.get('append', True)
 529         # get list of attributes users ar able to manage
 530         filter = {'category': '*slice*'}
 531         if not admin:
 532             filter['|roles'] = ['user']
 533         slice_attributes = self.driver.shell.GetTagTypes(filter)
 534         valid_slice_attribute_names = [attribute['tagname'] for attribute in slice_attributes]
 535
 536         # get sliver attributes
 537         added_slice_attributes = []
 538         removed_slice_attributes = []
 539         # we need to keep the slice hrn anyway
 540         ignored_slice_attribute_names = ['hrn']
 541         existing_slice_attributes = self.driver.shell.GetSliceTags({'slice_id': slice['slice_id']})
 542
 543         # get attributes that should be removed
 544         for slice_tag in existing_slice_attributes:
 545             if slice_tag['tagname'] in ignored_slice_attribute_names:
 546                 # If a slice already has a admin only role it was probably given to them by an
 547                 # admin, so we should ignore it.
 548                 ignored_slice_attribute_names.append(slice_tag['tagname'])
 549                 attribute_found=True
 550             else:
 551                 # If an existing slice attribute was not found in the request it should
 552                 # be removed
 553                 attribute_found=False
 554                 for requested_attribute in requested_slice_attributes:
 555                     if requested_attribute['name'] == slice_tag['tagname'] and \
 556                        requested_attribute['value'] == slice_tag['value']:
 557                         attribute_found=True
 558                         break
 559
 560             if not attribute_found and not append:
 561                 removed_slice_attributes.append(slice_tag)
 562
 563         # get attributes that should be added:
 564         for requested_attribute in requested_slice_attributes:
 565             # if the requested attribute wasn't found  we should add it
 566             if requested_attribute['name'] in valid_slice_attribute_names:
 567                 attribute_found = False
 568                 for existing_attribute in existing_slice_attributes:
 569                     if requested_attribute['name'] == existing_attribute['tagname'] and \
 570                        requested_attribute['value'] == existing_attribute['value']:
 571                         attribute_found=True
 572                         break
 573                 if not attribute_found:
 574                     added_slice_attributes.append(requested_attribute)
 575
 576
 577         # remove stale attributes
 578         for attribute in removed_slice_attributes:
 579             try:
 580                 self.driver.shell.DeleteSliceTag(attribute['slice_tag_id'])
 581             except Exception, e:
 582                 logger.warn('Failed to remove sliver attribute. name: %s, value: %s, node_id: %s\nCause:%s'\
 583                                 % (slice['name'], attribute['value'],  attribute.get('node_id'), str(e)))
 584
 585         # add requested_attributes
 586         for attribute in added_slice_attributes:
 587             try:
 588                 self.driver.shell.AddSliceTag(slice['name'], attribute['name'], attribute['value'], attribute.get('node_id', None))
 589             except Exception, e:
 590                 logger.warn('Failed to add sliver attribute. name: %s, value: %s, node_id: %s\nCause:%s'\
 591                                 % (slice['name'], attribute['value'],  attribute.get('node_id'), str(e)))
 592