sfa/planetlab/plslices.py

   1 from types import StringTypes
   2 from collections import defaultdict
   3
   4 from sfa.util.sfatime import utcparse, datetime_to_epoch
   5 from sfa.util.sfalogging import logger
   6 from sfa.util.xrn import Xrn, get_leaf, get_authority, urn_to_hrn
   7 from sfa.rspecs.rspec import RSpec
   8 from sfa.planetlab.vlink import VLink
   9 from sfa.planetlab.topology import Topology
  10 from sfa.planetlab.plxrn import PlXrn, hrn_to_pl_slicename
  11
  12 MAXINT =  2L**31-1
  13
  14 class PlSlices:
  15
  16     rspec_to_slice_tag = {'max_rate':'net_max_rate'}
  17
  18     def __init__(self, driver):
  19         self.driver = driver
  20
  21     def get_slivers(self, xrn, node=None):
  22         hrn, type = urn_to_hrn(xrn)
  23
  24         slice_name = hrn_to_pl_slicename(hrn)
  25         # XX Should we just call PLCAPI.GetSliceTicket(slice_name) instead
  26         # of doing all of this?
  27         #return self.driver.shell.GetSliceTicket(self.auth, slice_name)
  28
  29         # from PLCAPI.GetSlivers.get_slivers()
  30         slice_fields = ['slice_id', 'name', 'instantiation', 'expires', 'person_ids', 'slice_tag_ids']
  31         slices = self.driver.shell.GetSlices(slice_name, slice_fields)
  32         # Build up list of users and slice attributes
  33         person_ids = set()
  34         all_slice_tag_ids = set()
  35         for slice in slices:
  36             person_ids.update(slice['person_ids'])
  37             all_slice_tag_ids.update(slice['slice_tag_ids'])
  38         person_ids = list(person_ids)
  39         all_slice_tag_ids = list(all_slice_tag_ids)
  40         # Get user information
  41         all_persons_list = self.driver.shell.GetPersons({'person_id':person_ids,'enabled':True}, ['person_id', 'enabled', 'key_ids'])
  42         all_persons = {}
  43         for person in all_persons_list:
  44             all_persons[person['person_id']] = person
  45
  46         # Build up list of keys
  47         key_ids = set()
  48         for person in all_persons.values():
  49             key_ids.update(person['key_ids'])
  50         key_ids = list(key_ids)
  51         # Get user account keys
  52         all_keys_list = self.driver.shell.GetKeys(key_ids, ['key_id', 'key', 'key_type'])
  53         all_keys = {}
  54         for key in all_keys_list:
  55             all_keys[key['key_id']] = key
  56         # Get slice attributes
  57         all_slice_tags_list = self.driver.shell.GetSliceTags(all_slice_tag_ids)
  58         all_slice_tags = {}
  59         for slice_tag in all_slice_tags_list:
  60             all_slice_tags[slice_tag['slice_tag_id']] = slice_tag
  61
  62         slivers = []
  63         for slice in slices:
  64             keys = []
  65             for person_id in slice['person_ids']:
  66                 if person_id in all_persons:
  67                     person = all_persons[person_id]
  68                     if not person['enabled']:
  69                         continue
  70                     for key_id in person['key_ids']:
  71                         if key_id in all_keys:
  72                             key = all_keys[key_id]
  73                             keys += [{'key_type': key['key_type'],
  74                                     'key': key['key']}]
  75             attributes = []
  76             # All (per-node and global) attributes for this slice
  77             slice_tags = []
  78             for slice_tag_id in slice['slice_tag_ids']:
  79                 if slice_tag_id in all_slice_tags:
  80                     slice_tags.append(all_slice_tags[slice_tag_id])
  81             # Per-node sliver attributes take precedence over global
  82             # slice attributes, so set them first.
  83             # Then comes nodegroup slice attributes
  84             # Followed by global slice attributes
  85             sliver_attributes = []
  86
  87             if node is not None:
  88                 for sliver_attribute in filter(lambda a: a['node_id'] == node['node_id'], slice_tags):
  89                     sliver_attributes.append(sliver_attribute['tagname'])
  90                     attributes.append({'tagname': sliver_attribute['tagname'],
  91                                     'value': sliver_attribute['value']})
  92
  93             # set nodegroup slice attributes
  94             for slice_tag in filter(lambda a: a['nodegroup_id'] in node['nodegroup_ids'], slice_tags):
  95                 # Do not set any nodegroup slice attributes for
  96                 # which there is at least one sliver attribute
  97                 # already set.
  98                 if slice_tag not in slice_tags:
  99                     attributes.append({'tagname': slice_tag['tagname'],
 100                         'value': slice_tag['value']})
 101
 102             for slice_tag in filter(lambda a: a['node_id'] is None, slice_tags):
 103                 # Do not set any global slice attributes for
 104                 # which there is at least one sliver attribute
 105                 # already set.
 106                 if slice_tag['tagname'] not in sliver_attributes:
 107                     attributes.append({'tagname': slice_tag['tagname'],
 108                                    'value': slice_tag['value']})
 109
 110             # XXX Sanity check; though technically this should be a system invariant
 111             # checked with an assertion
 112             if slice['expires'] > MAXINT:  slice['expires']= MAXINT
 113
 114             slivers.append({
 115                 'hrn': hrn,
 116                 'name': slice['name'],
 117                 'slice_id': slice['slice_id'],
 118                 'instantiation': slice['instantiation'],
 119                 'expires': slice['expires'],
 120                 'keys': keys,
 121                 'attributes': attributes
 122             })
 123
 124         return slivers
 125
 126     def get_peer(self, xrn):
 127         hrn, type = urn_to_hrn(xrn)
 128         # Becaues of myplc federation,  we first need to determine if this
 129         # slice belongs to out local plc or a myplc peer. We will assume it
 130         # is a local site, unless we find out otherwise
 131         peer = None
 132
 133         # get this slice's authority (site)
 134         slice_authority = get_authority(hrn)
 135
 136         # get this site's authority (sfa root authority or sub authority)
 137         site_authority = get_authority(slice_authority).lower()
 138
 139         # check if we are already peered with this site_authority, if so
 140         peers = self.driver.shell.GetPeers({}, ['peer_id', 'peername', 'shortname', 'hrn_root'])
 141         for peer_record in peers:
 142             names = [name.lower() for name in peer_record.values() if isinstance(name, StringTypes)]
 143             if site_authority in names:
 144                 peer = peer_record
 145
 146         return peer
 147
 148     def get_sfa_peer(self, xrn):
 149         hrn, type = urn_to_hrn(xrn)
 150
 151         # return the authority for this hrn or None if we are the authority
 152         sfa_peer = None
 153         slice_authority = get_authority(hrn)
 154         site_authority = get_authority(slice_authority)
 155
 156         if site_authority != self.driver.hrn:
 157             sfa_peer = site_authority
 158
 159         return sfa_peer
 160
 161     def verify_slice_leases(self, slice, requested_leases, kept_leases, peer):
 162
 163         leases = self.driver.shell.GetLeases({'name':slice['name']}, ['lease_id'])
 164         grain = self.driver.shell.GetLeaseGranularity()
 165         current_leases = [lease['lease_id'] for lease in leases]
 166         deleted_leases = list(set(current_leases).difference(kept_leases))
 167
 168         try:
 169             if peer:
 170                 self.driver.shell.UnBindObjectFromPeer('slice', slice['slice_id'], peer['shortname'])
 171             deleted=self.driver.shell.DeleteLeases(deleted_leases)
 172             for lease in requested_leases:
 173                 added=self.driver.shell.AddLeases(lease['hostname'], slice['name'], int(lease['start_time']), int(lease['duration']) * grain + int(lease['start_time']))
 174
 175         except:
 176             logger.log_exc('Failed to add/remove slice leases')
 177
 178         return leases
 179
 180
 181     def verify_slice_nodes(self, slice, requested_slivers, peer):
 182
 183         nodes = self.driver.shell.GetNodes(slice['node_ids'], ['node_id', 'hostname', 'interface_ids'])
 184         current_slivers = [node['hostname'] for node in nodes]
 185
 186         # remove nodes not in rspec
 187         deleted_nodes = list(set(current_slivers).difference(requested_slivers))
 188
 189         # add nodes from rspec
 190         added_nodes = list(set(requested_slivers).difference(current_slivers))
 191
 192         try:
 193             if peer:
 194                 self.driver.shell.UnBindObjectFromPeer('slice', slice['slice_id'], peer['shortname'])
 195             self.driver.shell.AddSliceToNodes(slice['name'], added_nodes)
 196             self.driver.shell.DeleteSliceFromNodes(slice['name'], deleted_nodes)
 197
 198         except:
 199             logger.log_exc('Failed to add/remove slice from nodes')
 200         return nodes
 201
 202     def free_egre_key(self):
 203         used = set()
 204         for tag in self.driver.shell.GetSliceTags({'tagname': 'egre_key'}):
 205                 used.add(int(tag['value']))
 206
 207         for i in range(1, 256):
 208             if i not in used:
 209                 key = i
 210                 break
 211         else:
 212             raise KeyError("No more EGRE keys available")
 213
 214         return str(key)
 215
 216     def verify_slice_links(self, slice, requested_links, nodes):
 217
 218         if not requested_links:
 219             return
 220
 221         # exit if links are not supported here
 222         topology = Topology()
 223         if not topology:
 224             return
 225
 226         # build dict of nodes
 227         nodes_dict = {}
 228         interface_ids = []
 229         for node in nodes:
 230             nodes_dict[node['node_id']] = node
 231             interface_ids.extend(node['interface_ids'])
 232         # build dict of interfaces
 233         interfaces = self.driver.shell.GetInterfaces(interface_ids)
 234         interfaces_dict = {}
 235         for interface in interfaces:
 236             interfaces_dict[interface['interface_id']] = interface
 237
 238         slice_tags = []
 239
 240         # set egre key
 241         slice_tags.append({'name': 'egre_key', 'value': self.free_egre_key()})
 242
 243         # set netns
 244         slice_tags.append({'name': 'netns', 'value': '1'})
 245
 246         # set cap_net_admin
 247         # need to update the attribute string?
 248         slice_tags.append({'name': 'capabilities', 'value': 'CAP_NET_ADMIN'})
 249
 250         for link in requested_links:
 251             # get the ip address of the first node in the link
 252             ifname1 = Xrn(link['interface1']['component_id']).get_leaf()
 253             ifname_parts = ifname1.split(':')
 254             node_raw = ifname_parts[0]
 255             device = None
 256             if len(ifname_parts) > 1:
 257                 device = ifname_parts[1]
 258             node_id = int(node_raw.replace('node', ''))
 259             node = nodes_dict[node_id]
 260             if1 = interfaces_dict[node['interface_ids'][0]]
 261             ipaddr = if1['ip']
 262             topo_rspec = VLink.get_topo_rspec(link, ipaddr)
 263             # set topo_rspec tag
 264             slice_tags.append({'name': 'topo_rspec', 'value': str([topo_rspec]), 'node_id': node_id})
 265             # set vini_topo tag
 266             slice_tags.append({'name': 'vini_topo', 'value': 'manual', 'node_id': node_id})
 267             #self.driver.shell.AddSliceTag(slice['name'], 'topo_rspec', str([topo_rspec]), node_id)
 268
 269         self.verify_slice_attributes(slice, slice_tags, {'append': True}, admin=True)
 270
 271
 272
 273     def handle_peer(self, site, slice, persons, peer):
 274         if peer:
 275             # bind site
 276             try:
 277                 if site:
 278                     self.driver.shell.BindObjectToPeer('site', site['site_id'], peer['shortname'], slice['site_id'])
 279             except Exception,e:
 280                 self.driver.shell.DeleteSite(site['site_id'])
 281                 raise e
 282
 283             # bind slice
 284             try:
 285                 if slice:
 286                     self.driver.shell.BindObjectToPeer('slice', slice['slice_id'], peer['shortname'], slice['slice_id'])
 287             except Exception,e:
 288                 self.driver.shell.DeleteSlice(slice['slice_id'])
 289                 raise e
 290
 291             # bind persons
 292             for person in persons:
 293                 try:
 294                     self.driver.shell.BindObjectToPeer('person',
 295                                                      person['person_id'], peer['shortname'], person['peer_person_id'])
 296
 297                     for (key, remote_key_id) in zip(person['keys'], person['key_ids']):
 298                         try:
 299                             self.driver.shell.BindObjectToPeer( 'key', key['key_id'], peer['shortname'], remote_key_id)
 300                         except:
 301                             self.driver.shell.DeleteKey(key['key_id'])
 302                             logger("failed to bind key: %s to peer: %s " % (key['key_id'], peer['shortname']))
 303                 except Exception,e:
 304                     self.driver.shell.DeletePerson(person['person_id'])
 305                     raise e
 306
 307         return slice
 308
 309     def verify_site(self, slice_xrn, slice_record={}, peer=None, sfa_peer=None, options={}):
 310         (slice_hrn, type) = urn_to_hrn(slice_xrn)
 311         site_hrn = get_authority(slice_hrn)
 312         # login base can't be longer than 20 characters
 313         slicename = hrn_to_pl_slicename(slice_hrn)
 314         authority_name = slicename.split('_')[0]
 315         login_base = authority_name[:20]
 316         sites = self.driver.shell.GetSites(login_base)
 317         if not sites:
 318             # create new site record
 319             site = {'name': 'geni.%s' % authority_name,
 320                     'abbreviated_name': authority_name,
 321                     'login_base': login_base,
 322                     'max_slices': 100,
 323                     'max_slivers': 1000,
 324                     'enabled': True,
 325                     'peer_site_id': None}
 326             if peer:
 327                 site['peer_site_id'] = slice_record.get('site_id', None)
 328             site['site_id'] = self.driver.shell.AddSite(site)
 329             # exempt federated sites from monitor policies
 330             self.driver.shell.AddSiteTag(site['site_id'], 'exempt_site_until', "20200101")
 331
 332 #            # is this still necessary?
 333 #            # add record to the local registry
 334 #            if sfa_peer and slice_record:
 335 #                peer_dict = {'type': 'authority', 'hrn': site_hrn, \
 336 #                             'peer_authority': sfa_peer, 'pointer': site['site_id']}
 337 #                self.registry.register_peer_object(self.credential, peer_dict)
 338         else:
 339             site =  sites[0]
 340             if peer:
 341                 # unbind from peer so we can modify if necessary. Will bind back later
 342                 self.driver.shell.UnBindObjectFromPeer('site', site['site_id'], peer['shortname'])
 343
 344         return site
 345
 346     def verify_slice(self, slice_hrn, slice_record, peer, sfa_peer, options={}):
 347         slicename = hrn_to_pl_slicename(slice_hrn)
 348         parts = slicename.split("_")
 349         login_base = parts[0]
 350         slices = self.driver.shell.GetSlices([slicename])
 351         if not slices:
 352             slice = {'name': slicename,
 353                      'url': 'No Url',
 354                      'description': 'No Description'}
 355             # add the slice
 356             slice['slice_id'] = self.driver.shell.AddSlice(slice)
 357             slice['node_ids'] = []
 358             slice['person_ids'] = []
 359             if peer and slice_record:
 360                 slice['peer_slice_id'] = slice_record.get('slice_id', None)
 361         else:
 362             slice = slices[0]
 363             if peer and slice_record:
 364                 slice['peer_slice_id'] = slice_record.get('slice_id', None)
 365                 # unbind from peer so we can modify if necessary. Will bind back later
 366                 self.driver.shell.UnBindObjectFromPeer('slice', slice['slice_id'], peer['shortname'])
 367                 #Update existing record (e.g. expires field) it with the latest info.
 368             if slice_record and slice_record.get('expires'):
 369                 requested_expires = int(datetime_to_epoch(utcparse(slice_record['expires'])))
 370                 if requested_expires and slice['expires'] != requested_expires:
 371                     self.driver.shell.UpdateSlice( slice['slice_id'], {'expires' : requested_expires})
 372
 373         return slice
 374
 375     #def get_existing_persons(self, users):
 376     def verify_persons(self, slice_hrn, slice_record, users, peer, sfa_peer, options={}):
 377         users_by_email = {}
 378         users_by_site = defaultdict(list)
 379         users_dict = {}
 380         for user in users:
 381             user['urn'] = user['urn'].lower()
 382             hrn, type = urn_to_hrn(user['urn'])
 383             username = get_leaf(hrn)
 384             login_base = PlXrn(xrn=user['urn']).pl_login_base()
 385             user['username'] = username
 386             user['site'] = login_base
 387
 388             if 'email' in user:
 389                 user['email'] = user['email'].lower()
 390                 users_by_email[user['email']] = user
 391                 users_dict[user['email']] = user
 392             else:
 393                 users_by_site[user['site']].append(user)
 394
 395         # start building a list of existing users
 396         existing_user_ids = []
 397         existing_user_ids_filter = []
 398         if users_by_email:
 399             existing_user_ids_filter.extend(users_by_email.keys())
 400         if users_by_site:
 401             for login_base in users_by_site:
 402                 users = users_by_site[login_base]
 403                 for user in users:
 404                     existing_user_ids_filter.append(user['username']+'@geni.net')
 405         if existing_user_ids_filter:
 406             # get existing users by email
 407             existing_users = self.driver.shell.GetPersons({'email': existing_user_ids_filter},
 408                                                         ['person_id', 'key_ids', 'email'])
 409             existing_user_ids.extend([user['email'] for user in existing_users])
 410
 411         if users_by_site:
 412             # get a list of user sites (based on requeste user urns
 413             site_list = self.driver.shell.GetSites(users_by_site.keys(), \
 414                 ['site_id', 'login_base', 'person_ids'])
 415             # get all existing users at these sites
 416             sites = {}
 417             site_user_ids = []
 418             for site in site_list:
 419                 sites[site['site_id']] = site
 420                 site_user_ids.extend(site['person_ids'])
 421
 422             existing_site_persons_list = self.driver.shell.GetPersons(site_user_ids,
 423                                                                     ['person_id', 'key_ids', 'email', 'site_ids'])
 424
 425             # all requested users are either existing users or new (added) users
 426             for login_base in users_by_site:
 427                 requested_site_users = users_by_site[login_base]
 428                 for requested_user in requested_site_users:
 429                     user_found = False
 430                     for existing_user in existing_site_persons_list:
 431                         for site_id in existing_user['site_ids']:
 432                             if site_id in sites:
 433                                 site = sites[site_id]
 434                                 if login_base == site['login_base'] and \
 435                                    existing_user['email'].startswith(requested_user['username']+'@'):
 436                                     existing_user_ids.append(existing_user['email'])
 437                                     requested_user['email'] = existing_user['email']
 438                                     users_dict[existing_user['email']] = requested_user
 439                                     user_found = True
 440                                     break
 441                         if user_found:
 442                             break
 443
 444                     if user_found == False:
 445                         fake_email = requested_user['username'] + '@geni.net'
 446                         requested_user['email'] = fake_email
 447                         users_dict[fake_email] = requested_user
 448
 449         # requested slice users
 450         requested_user_ids = users_dict.keys()
 451         # existing slice users
 452         existing_slice_users_filter = {'person_id': slice_record.get('person_ids', [])}
 453         existing_slice_users = self.driver.shell.GetPersons(existing_slice_users_filter,
 454                                                           ['person_id', 'key_ids', 'email'])
 455         existing_slice_user_ids = [user['email'] for user in existing_slice_users]
 456
 457         # users to be added, removed or updated
 458         added_user_ids = set(requested_user_ids).difference(existing_user_ids)
 459         added_slice_user_ids = set(requested_user_ids).difference(existing_slice_user_ids)
 460         removed_user_ids = set(existing_slice_user_ids).difference(requested_user_ids)
 461         updated_user_ids = set(existing_slice_user_ids).intersection(requested_user_ids)
 462
 463         # Remove stale users (only if we are not appending).
 464         # Append by default.
 465         append = options.get('append', True)
 466         if append == False:
 467             for removed_user_id in removed_user_ids:
 468                 self.driver.shell.DeletePersonFromSlice(removed_user_id, slice_record['name'])
 469         # update_existing users
 470         updated_users_list = [user for user in users_dict.values() if user['email'] in \
 471           updated_user_ids]
 472         self.verify_keys(existing_slice_users, updated_users_list, peer, options)
 473
 474         added_persons = []
 475         # add new users
 476         for added_user_id in added_user_ids:
 477             added_user = users_dict[added_user_id]
 478             hrn, type = urn_to_hrn(added_user['urn'])
 479             person = {
 480                 'first_name': added_user.get('first_name', hrn),
 481                 'last_name': added_user.get('last_name', hrn),
 482                 'email': added_user_id,
 483                 'peer_person_id': None,
 484                 'keys': [],
 485                 'key_ids': added_user.get('key_ids', []),
 486             }
 487             person['person_id'] = self.driver.shell.AddPerson(person)
 488             if peer:
 489                 person['peer_person_id'] = added_user['person_id']
 490             added_persons.append(person)
 491
 492             # enable the account
 493             self.driver.shell.UpdatePerson(person['person_id'], {'enabled': True})
 494
 495             # add person to site
 496             self.driver.shell.AddPersonToSite(added_user_id, added_user['site'])
 497
 498             for key_string in added_user.get('keys', []):
 499                 key = {'key':key_string, 'key_type':'ssh'}
 500                 key['key_id'] = self.driver.shell.AddPersonKey(person['person_id'], key)
 501                 person['keys'].append(key)
 502
 503             # add the registry record
 504 #            if sfa_peer:
 505 #                peer_dict = {'type': 'user', 'hrn': hrn, 'peer_authority': sfa_peer, \
 506 #                    'pointer': person['person_id']}
 507 #                self.registry.register_peer_object(self.credential, peer_dict)
 508
 509         for added_slice_user_id in added_slice_user_ids.union(added_user_ids):
 510             # add person to the slice
 511             self.driver.shell.AddPersonToSlice(added_slice_user_id, slice_record['name'])
 512             # if this is a peer record then it should already be bound to a peer.
 513             # no need to return worry about it getting bound later
 514
 515         return added_persons
 516
 517
 518     def verify_keys(self, persons, users, peer, options={}):
 519         # existing keys
 520         key_ids = []
 521         for person in persons:
 522             key_ids.extend(person['key_ids'])
 523         keylist = self.driver.shell.GetKeys(key_ids, ['key_id', 'key'])
 524         keydict = {}
 525         for key in keylist:
 526             keydict[key['key']] = key['key_id']
 527         existing_keys = keydict.keys()
 528         persondict = {}
 529         for person in persons:
 530             persondict[person['email']] = person
 531
 532         # add new keys
 533         requested_keys = []
 534         updated_persons = []
 535         for user in users:
 536             user_keys = user.get('keys', [])
 537             updated_persons.append(user)
 538             for key_string in user_keys:
 539                 requested_keys.append(key_string)
 540                 if key_string not in existing_keys:
 541                     key = {'key': key_string, 'key_type': 'ssh'}
 542                     try:
 543                         if peer:
 544                             person = persondict[user['email']]
 545                             self.driver.shell.UnBindObjectFromPeer('person', person['person_id'], peer['shortname'])
 546                         key['key_id'] = self.driver.shell.AddPersonKey(user['email'], key)
 547                         if peer:
 548                             key_index = user_keys.index(key['key'])
 549                             remote_key_id = user['key_ids'][key_index]
 550                             self.driver.shell.BindObjectToPeer('key', key['key_id'], peer['shortname'], remote_key_id)
 551
 552                     finally:
 553                         if peer:
 554                             self.driver.shell.BindObjectToPeer('person', person['person_id'], peer['shortname'], user['person_id'])
 555
 556         # remove old keys (only if we are not appending)
 557         append = options.get('append', True)
 558         if append == False:
 559             removed_keys = set(existing_keys).difference(requested_keys)
 560             for existing_key_id in keydict:
 561                 if keydict[existing_key_id] in removed_keys:
 562                     try:
 563                         if peer:
 564                             self.driver.shell.UnBindObjectFromPeer('key', existing_key_id, peer['shortname'])
 565                         self.driver.shell.DeleteKey(existing_key_id)
 566                     except:
 567                         pass
 568
 569     def verify_slice_attributes(self, slice, requested_slice_attributes, options={}, admin=False):
 570         append = options.get('append', True)
 571         # get list of attributes users ar able to manage
 572         filter = {'category': '*slice*'}
 573         if not admin:
 574             filter['|roles'] = ['user']
 575         slice_attributes = self.driver.shell.GetTagTypes(filter)
 576         valid_slice_attribute_names = [attribute['tagname'] for attribute in slice_attributes]
 577
 578         # get sliver attributes
 579         added_slice_attributes = []
 580         removed_slice_attributes = []
 581         ignored_slice_attribute_names = []
 582         existing_slice_attributes = self.driver.shell.GetSliceTags({'slice_id': slice['slice_id']})
 583
 584         # get attributes that should be removed
 585         for slice_tag in existing_slice_attributes:
 586             if slice_tag['tagname'] in ignored_slice_attribute_names:
 587                 # If a slice already has a admin only role it was probably given to them by an
 588                 # admin, so we should ignore it.
 589                 ignored_slice_attribute_names.append(slice_tag['tagname'])
 590             else:
 591                 # If an existing slice attribute was not found in the request it should
 592                 # be removed
 593                 attribute_found=False
 594                 for requested_attribute in requested_slice_attributes:
 595                     if requested_attribute['name'] == slice_tag['tagname'] and \
 596                        requested_attribute['value'] == slice_tag['value']:
 597                         attribute_found=True
 598                         break
 599
 600             if not attribute_found and not append:
 601                 removed_slice_attributes.append(slice_tag)
 602
 603         # get attributes that should be added:
 604         for requested_attribute in requested_slice_attributes:
 605             # if the requested attribute wasn't found  we should add it
 606             if requested_attribute['name'] in valid_slice_attribute_names:
 607                 attribute_found = False
 608                 for existing_attribute in existing_slice_attributes:
 609                     if requested_attribute['name'] == existing_attribute['tagname'] and \
 610                        requested_attribute['value'] == existing_attribute['value']:
 611                         attribute_found=True
 612                         break
 613                 if not attribute_found:
 614                     added_slice_attributes.append(requested_attribute)
 615
 616
 617         # remove stale attributes
 618         for attribute in removed_slice_attributes:
 619             try:
 620                 self.driver.shell.DeleteSliceTag(attribute['slice_tag_id'])
 621             except Exception, e:
 622                 logger.warn('Failed to remove sliver attribute. name: %s, value: %s, node_id: %s\nCause:%s'\
 623                                 % (slice['name'], attribute['value'],  attribute.get('node_id'), str(e)))
 624
 625         # add requested_attributes
 626         for attribute in added_slice_attributes:
 627             try:
 628                 self.driver.shell.AddSliceTag(slice['name'], attribute['name'], attribute['value'], attribute.get('node_id', None))
 629             except Exception, e:
 630                 logger.warn('Failed to add sliver attribute. name: %s, value: %s, node_id: %s\nCause:%s'\
 631                                 % (slice['name'], attribute['value'],  attribute.get('node_id'), str(e)))
 632