src/nepi/core/execute.py

   1 #!/usr/bin/env python
   2 # -*- coding: utf-8 -*-
   3
   4 from nepi.core.attributes import Attribute, AttributesMap
   5 from nepi.core.connector import ConnectorTypeBase
   6 from nepi.util import proxy, validation
   7 from nepi.util.constants import STATUS_FINISHED, TIME_NOW
   8 from nepi.util.parser._xml import XmlExperimentParser
   9 import sys
  10 import re
  11 import threading
  12 import ConfigParser
  13 import os
  14
  15 ATTRIBUTE_PATTERN_BASE = re.compile(r"\{#\[(?P<label>[-a-zA-Z0-9._]*)\](?P<expr>(?P<component>\.addr\[[0-9]+\]|\.route\[[0-9]+\]|\.trace\[[0-9]+\]|).\[(?P<attribute>[-a-zA-Z0-9._]*)\])#}")
  16 ATTRIBUTE_PATTERN_GUID_SUB = r"{#[%(guid)s]%(expr)s#}"
  17 COMPONENT_PATTERN = re.compile(r"(?P<kind>[a-z]*)\[(?P<index>.*)\]")
  18
  19 class ConnectorType(ConnectorTypeBase):
  20     def __init__(self, testbed_id, factory_id, name, max = -1, min = 0):
  21         super(ConnectorType, self).__init__(testbed_id, factory_id, name, max, min)
  22         # from_connections -- connections where the other connector is the "From"
  23         # to_connections -- connections where the other connector is the "To"
  24         # keys in the dictionary correspond to the
  25         # connector_type_id for possible connections. The value is a tuple:
  26         # (can_cross, connect)
  27         # can_cross: indicates if the connection is allowed accros different
  28         #    testbed instances
  29         # code: is the connection function to be invoked when the elements
  30         #    are connected
  31         self._from_connections = dict()
  32         self._to_connections = dict()
  33
  34     def add_from_connection(self, testbed_id, factory_id, name, can_cross,
  35             init_code, compl_code):
  36         type_id = self.make_connector_type_id(testbed_id, factory_id, name)
  37         self._from_connections[type_id] = (can_cross, init_code, compl_code)
  38
  39     def add_to_connection(self, testbed_id, factory_id, name, can_cross,
  40             init_code, compl_code):
  41         type_id = self.make_connector_type_id(testbed_id, factory_id, name)
  42         self._to_connections[type_id] = (can_cross, init_code, compl_code)
  43
  44     def can_connect(self, testbed_id, factory_id, name, count,
  45             must_cross = False):
  46         connector_type_id = self.make_connector_type_id(testbed_id, factory_id, name)
  47         for lookup_type_id in self._type_resolution_order(connector_type_id):
  48             if lookup_type_id in self._from_connections:
  49                 (can_cross, init_code, compl_code) = self._from_connections[lookup_type_id]
  50             elif lookup_type_id in self._to_connections:
  51                 (can_cross, init_code, compl_code) = self._to_connections[lookup_type_id]
  52             else:
  53                 # keey trying
  54                 continue
  55             return not must_cross or can_cross
  56         else:
  57             return False
  58
  59     def _connect_to_code(self, testbed_id, factory_id, name):
  60         connector_type_id = self.make_connector_type_id(testbed_id, factory_id, name)
  61         for lookup_type_id in self._type_resolution_order(connector_type_id):
  62             if lookup_type_id in self._to_connections:
  63                 (can_cross, init_code, compl_code) = self._to_connections[lookup_type_id]
  64                 return (init_code, compl_code)
  65         else:
  66             return (False, False)
  67
  68     def connect_to_init_code(self, testbed_id, factory_id, name):
  69         return self._connect_to_code(testbed_id, factory_id, name)[0]
  70
  71     def connect_to_compl_code(self, testbed_id, factory_id, name):
  72         return self._connect_to_code(testbed_id, factory_id, name)[1]
  73
  74 class Factory(AttributesMap):
  75     def __init__(self, factory_id, create_function, start_function,
  76             stop_function, status_function,
  77             configure_function, preconfigure_function,
  78             allow_addresses = False, has_addresses = False,
  79             allow_routes = False, has_routes = False):
  80         super(Factory, self).__init__()
  81         self._factory_id = factory_id
  82         self._allow_addresses = bool(allow_addresses)
  83         self._allow_routes = bool(allow_routes)
  84         self._has_addresses = bool(has_addresses) or self._allow_addresses
  85         self._has_routes = bool(has_routes) or self._allow_routes
  86         self._create_function = create_function
  87         self._start_function = start_function
  88         self._stop_function = stop_function
  89         self._status_function = status_function
  90         self._configure_function = configure_function
  91         self._preconfigure_function = preconfigure_function
  92         self._connector_types = dict()
  93         self._traces = list()
  94         self._box_attributes = AttributesMap()
  95
  96     @property
  97     def factory_id(self):
  98         return self._factory_id
  99
 100     @property
 101     def allow_addresses(self):
 102         return self._allow_addresses
 103
 104     @property
 105     def allow_routes(self):
 106         return self._allow_routes
 107
 108     @property
 109     def has_addresses(self):
 110         return self._has_addresses
 111
 112     @property
 113     def has_routes(self):
 114         return self._has_routes
 115
 116     @property
 117     def box_attributes(self):
 118         return self._box_attributes
 119
 120     @property
 121     def create_function(self):
 122         return self._create_function
 123
 124     @property
 125     def start_function(self):
 126         return self._start_function
 127
 128     @property
 129     def stop_function(self):
 130         return self._stop_function
 131
 132     @property
 133     def status_function(self):
 134         return self._status_function
 135
 136     @property
 137     def configure_function(self):
 138         return self._configure_function
 139
 140     @property
 141     def preconfigure_function(self):
 142         return self._preconfigure_function
 143
 144     @property
 145     def traces(self):
 146         return self._traces
 147
 148     def connector_type(self, name):
 149         return self._connector_types[name]
 150
 151     def add_connector_type(self, connector_type):
 152         self._connector_types[connector_type.name] = connector_type
 153
 154     def add_trace(self, trace_id):
 155         self._traces.append(trace_id)
 156
 157     def add_box_attribute(self, name, help, type, value = None, range = None,
 158         allowed = None, flags = Attribute.NoFlags, validation_function = None):
 159         self._box_attributes.add_attribute(name, help, type, value, range,
 160                 allowed, flags, validation_function)
 161
 162 class TestbedController(object):
 163     def __init__(self, testbed_id, testbed_version):
 164         self._testbed_id = testbed_id
 165         self._testbed_version = testbed_version
 166
 167     @property
 168     def guids(self):
 169         raise NotImplementedError
 170
 171     def defer_configure(self, name, value):
 172         """Instructs setting a configuartion attribute for the testbed instance"""
 173         raise NotImplementedError
 174
 175     def defer_create(self, guid, factory_id):
 176         """Instructs creation of element """
 177         raise NotImplementedError
 178
 179     def defer_create_set(self, guid, name, value):
 180         """Instructs setting an initial attribute on an element"""
 181         raise NotImplementedError
 182
 183     def defer_factory_set(self, guid, name, value):
 184         """Instructs setting an attribute on a factory"""
 185         raise NotImplementedError
 186
 187     def defer_connect(self, guid1, connector_type_name1, guid2,
 188             connector_type_name2):
 189         """Instructs creation of a connection between the given connectors"""
 190         raise NotImplementedError
 191
 192     def defer_cross_connect(self, guid, connector_type_name, cross_guid,
 193             cross_testbed_id, cross_factory_id, cross_connector_type_name):
 194         """
 195         Instructs creation of a connection between the given connectors
 196         of different testbed instances
 197         """
 198         raise NotImplementedError
 199
 200     def defer_add_trace(self, guid, trace_id):
 201         """Instructs the addition of a trace"""
 202         raise NotImplementedError
 203
 204     def defer_add_address(self, guid, address, netprefix, broadcast):
 205         """Instructs the addition of an address"""
 206         raise NotImplementedError
 207
 208     def defer_add_route(self, guid, destination, netprefix, nexthop):
 209         """Instructs the addition of a route"""
 210         raise NotImplementedError
 211
 212     def do_setup(self):
 213         """After do_setup the testbed initial configuration is done"""
 214         raise NotImplementedError
 215
 216     def do_create(self):
 217         """
 218         After do_create all instructed elements are created and
 219         attributes setted
 220         """
 221         raise NotImplementedError
 222
 223     def do_connect_init(self):
 224         """
 225         After do_connect_init all internal connections between testbed elements
 226         are initiated
 227         """
 228         raise NotImplementedError
 229
 230     def do_connect_compl(self):
 231         """
 232         After do_connect all internal connections between testbed elements
 233         are completed
 234         """
 235         raise NotImplementedError
 236
 237     def do_configure(self):
 238         """After do_configure elements are configured"""
 239         raise NotImplementedError
 240
 241     def do_cross_connect_init(self, cross_data):
 242         """
 243         After do_cross_connect_init initiation of all external connections
 244         between different testbed elements is performed
 245         """
 246         raise NotImplementedError
 247
 248     def do_cross_connect_compl(self, cross_data):
 249         """
 250         After do_cross_connect_compl completion of all external connections
 251         between different testbed elements is performed
 252         """
 253         raise NotImplementedError
 254
 255     def start(self):
 256         raise NotImplementedError
 257
 258     def stop(self):
 259         raise NotImplementedError
 260
 261     def set(self, time, guid, name, value):
 262         raise NotImplementedError
 263
 264     def get(self, time, guid, name):
 265         raise NotImplementedError
 266
 267     def get_route(self, guid, index, attribute):
 268         """
 269         Params:
 270
 271             guid: guid of box to query
 272             index: number of routing entry to fetch
 273             attribute: one of Destination, NextHop, NetPrefix
 274         """
 275         raise NotImplementedError
 276
 277     def get_address(self, guid, index, attribute='Address'):
 278         """
 279         Params:
 280
 281             guid: guid of box to query
 282             index: number of inteface to select
 283             attribute: one of Address, NetPrefix, Broadcast
 284         """
 285         raise NotImplementedError
 286
 287     def get_attribute_list(self, guid):
 288         raise NotImplementedError
 289
 290     def action(self, time, guid, action):
 291         raise NotImplementedError
 292
 293     def status(self, guid):
 294         raise NotImplementedError
 295
 296     def trace(self, guid, trace_id, attribute='value'):
 297         raise NotImplementedError
 298
 299     def shutdown(self):
 300         raise NotImplementedError
 301
 302 class ExperimentController(object):
 303     def __init__(self, experiment_xml, root_dir):
 304         self._experiment_xml = experiment_xml
 305         self._testbeds = dict()
 306         self._access_config = dict()
 307         self._netrefs = dict()
 308         self._cross_data = dict()
 309         self._root_dir = root_dir
 310
 311         self.persist_experiment_xml()
 312
 313     @property
 314     def experiment_xml(self):
 315         return self._experiment_xml
 316
 317     def persist_experiment_xml(self):
 318         xml_path = os.path.join(self._root_dir, "experiment.xml")
 319         f = open(xml_path, "w")
 320         f.write(self._experiment_xml)
 321         f.close()
 322
 323     def set_access_configuration(self, testbed_guid, access_config):
 324         self._access_config[testbed_guid] = access_config
 325
 326     def trace(self, testbed_guid, guid, trace_id, attribute='value'):
 327         return self._testbeds[testbed_guid].trace(guid, trace_id, attribute)
 328
 329     @staticmethod
 330     def _parallel(callables):
 331         threads = [ threading.Thread(target=callable) for callable in callables ]
 332         for thread in threads:
 333             thread.start()
 334         for thread in threads:
 335             thread.join()
 336
 337     def start(self):
 338         self._init_testbed_controllers()
 339
 340         # persist testbed connection data, for potential recovery
 341         self._persist_testbed_proxies()
 342
 343         # perform setup in parallel for all test beds,
 344         # wait for all threads to finish
 345         self._parallel([testbed.do_setup
 346                         for testbed in self._testbeds.itervalues()])
 347
 348         # perform create-connect in parallel, wait
 349         # (internal connections only)
 350         self._parallel([lambda : testbed.do_create()
 351                         for testbed in self._testbeds.itervalues()])
 352
 353         self._parallel([lambda : testbed.do_connect_init()
 354                         for testbed in self._testbeds.itervalues()])
 355
 356         self._parallel([lambda : testbed.do_connect_compl()
 357                         for testbed in self._testbeds.itervalues()])
 358
 359         self._parallel([lambda : testbed.do_preconfigure()
 360                         for testbed in self._testbeds.itervalues()])
 361
 362         # resolve netrefs
 363         self.do_netrefs(fail_if_undefined=True)
 364
 365         # perform do_configure in parallel for al testbeds
 366         # (it's internal configuration for each)
 367         self._parallel([testbed.do_configure
 368                         for testbed in self._testbeds.itervalues()])
 369
 370         # cross-connect (cannot be done in parallel)
 371         for guid, testbed in self._testbeds.iteritems():
 372             cross_data = self._get_cross_data(guid)
 373             testbed.do_cross_connect_init(cross_data)
 374         for guid, testbed in self._testbeds.iteritems():
 375             cross_data = self._get_cross_data(guid)
 376             testbed.do_cross_connect_compl(cross_data)
 377
 378         # start experiment (parallel start on all testbeds)
 379         self._parallel([testbed.start
 380                         for testbed in self._testbeds.itervalues()])
 381
 382     def _persist_testbed_proxies(self):
 383         TRANSIENT = ('Recover',)
 384
 385         # persist access configuration for all testbeds, so that
 386         # recovery mode can reconnect to them if it becomes necessary
 387         conf = ConfigParser.RawConfigParser()
 388         for testbed_guid, testbed_config in self._access_config.iteritems():
 389             testbed_guid = str(testbed_guid)
 390             conf.add_section(testbed_guid)
 391             for attr in testbed_config.attributes_list:
 392                 if attr not in TRANSIENT:
 393                     conf.set(testbed_guid, attr,
 394                         testbed_config.get_attribute_value(attr))
 395
 396         f = open(os.path.join(self._root_dir, 'access_config.ini'), 'w')
 397         conf.write(f)
 398         f.close()
 399
 400     def _load_testbed_proxies(self):
 401         TYPEMAP = {
 402             STRING : 'get',
 403             INTEGER : 'getint',
 404             FLOAT : 'getfloat',
 405             BOOLEAN : 'getboolean',
 406         }
 407
 408         conf = ConfigParser.RawConfigParser()
 409         conf.read(os.path.join(self._root_dir, 'access_config.ini'))
 410         for testbed_guid in conf.sections():
 411             testbed_config = proxy.AccessConfiguration()
 412             for attr in conf.options(testbed_guid):
 413                 testbed_config.set_attribute_value(attr,
 414                     conf.get(testbed_guid, attr) )
 415
 416             testbed_guid = str(testbed_guid)
 417             conf.add_section(testbed_guid)
 418             for attr in testbed_config.attributes_list:
 419                 if attr not in TRANSIENT:
 420                     getter = getattr(conf, TYPEMAP.get(
 421                         testbed_config.get_attribute_type(attr),
 422                         'get') )
 423                     testbed_config.set_attribute_value(
 424                         testbed_guid, attr, getter(attr))
 425
 426     def _unpersist_testbed_proxies(self):
 427         try:
 428             os.remove(os.path.join(self._root_dir, 'access_config.ini'))
 429         except:
 430             # Just print exceptions, this is just cleanup
 431             import traceback
 432             traceback.print_exc(file=sys.stderr)
 433
 434     def stop(self):
 435        for testbed in self._testbeds.values():
 436            testbed.stop()
 437        self._unpersist_testbed_proxies()
 438
 439     def recover(self):
 440         # reload perviously persisted testbed access configurations
 441         self._load_testbed_proxies()
 442
 443         # recreate testbed proxies by reconnecting only
 444         self._init_testbed_controllers(recover = True)
 445
 446     def is_finished(self, guid):
 447         for testbed in self._testbeds.values():
 448             for guid_ in testbed.guids:
 449                 if guid_ == guid:
 450                     return testbed.status(guid) == STATUS_FINISHED
 451         raise RuntimeError("No element exists with guid %d" % guid)
 452
 453     def shutdown(self):
 454        for testbed in self._testbeds.values():
 455            testbed.shutdown()
 456
 457     @staticmethod
 458     def _netref_component_split(component):
 459         match = COMPONENT_PATTERN.match(component)
 460         if match:
 461             return match.group("kind"), match.group("index")
 462         else:
 463             return component, None
 464
 465     def do_netrefs(self, fail_if_undefined = False):
 466         COMPONENT_GETTERS = {
 467             'addr' :
 468                 lambda testbed, guid, index, name :
 469                     testbed.get_address(guid, index, name),
 470             'route' :
 471                 lambda testbed, guid, index, name :
 472                     testbed.get_route(guid, index, name),
 473             'trace' :
 474                 lambda testbed, guid, index, name :
 475                     testbed.trace(guid, index, name),
 476             '' :
 477                 lambda testbed, guid, index, name :
 478                     testbed.get(TIME_NOW, guid, name),
 479         }
 480
 481         for (testbed_guid, guid), attrs in self._netrefs.iteritems():
 482             testbed = self._testbeds[testbed_guid]
 483             for name in attrs:
 484                 value = testbed.get(TIME_NOW, guid, name)
 485                 if isinstance(value, basestring):
 486                     match = ATTRIBUTE_PATTERN_BASE.search(value)
 487                     if match:
 488                         label = match.group("label")
 489                         if label.startswith('GUID-'):
 490                             ref_guid = int(label[5:])
 491                             if ref_guid:
 492                                 expr = match.group("expr")
 493                                 component = match.group("component")[1:] # skip the dot
 494                                 attribute = match.group("attribute")
 495
 496                                 # split compound components into component kind and index
 497                                 # eg: 'addr[0]' -> ('addr', '0')
 498                                 component, component_index = self._netref_component_split(component)
 499
 500                                 # find object and resolve expression
 501                                 for ref_testbed in self._testbeds.itervalues():
 502                                     if component not in COMPONENT_GETTERS:
 503                                         raise ValueError, "Malformed netref: %r - unknown component" % (expr,)
 504                                     else:
 505                                         ref_value = COMPONENT_GETTERS[component](
 506                                             ref_testbed, ref_guid, component_index, attribute)
 507                                         if ref_value:
 508                                             testbed.set(TIME_NOW, guid, name,
 509                                                 value.replace(match.group(), ref_value))
 510                                             break
 511                                 else:
 512                                     # couldn't find value
 513                                     if fail_if_undefined:
 514                                         raise ValueError, "Unresolvable GUID: %r, in netref: %r" % (ref_guid, expr)
 515
 516     def _init_testbed_controllers(self, recover = False):
 517         parser = XmlExperimentParser()
 518         data = parser.from_xml_to_data(self._experiment_xml)
 519         element_guids = list()
 520         label_guids = dict()
 521         data_guids = data.guids
 522
 523         # create testbed controllers
 524         for guid in data_guids:
 525             if data.is_testbed_data(guid):
 526                 self._create_testbed_controller(guid, data, element_guids,
 527                         recover)
 528             else:
 529                 element_guids.append(guid)
 530                 label = data.get_attribute_data(guid, "label")
 531                 if label is not None:
 532                     if label in label_guids:
 533                         raise RuntimeError, "Label %r is not unique" % (label,)
 534                     label_guids[label] = guid
 535
 536         # replace references to elements labels for its guid
 537         self._resolve_labels(data, data_guids, label_guids)
 538
 539         # program testbed controllers
 540         if not recover:
 541             self._program_testbed_controllers(element_guids, data)
 542
 543     def _resolve_labels(self, data, data_guids, label_guids):
 544         netrefs = self._netrefs
 545         for guid in data_guids:
 546             if not data.is_testbed_data(guid):
 547                 for name, value in data.get_attribute_data(guid):
 548                     if isinstance(value, basestring):
 549                         match = ATTRIBUTE_PATTERN_BASE.search(value)
 550                         if match:
 551                             label = match.group("label")
 552                             if not label.startswith('GUID-'):
 553                                 ref_guid = label_guids.get(label)
 554                                 if ref_guid is not None:
 555                                     value = ATTRIBUTE_PATTERN_BASE.sub(
 556                                         ATTRIBUTE_PATTERN_GUID_SUB % dict(
 557                                             guid = 'GUID-%d' % (ref_guid,),
 558                                             expr = match.group("expr"),
 559                                             label = label),
 560                                         value)
 561                                     data.set_attribute_data(guid, name, value)
 562
 563                                     # memorize which guid-attribute pairs require
 564                                     # postprocessing, to avoid excessive controller-testbed
 565                                     # communication at configuration time
 566                                     # (which could require high-latency network I/O)
 567                                     (testbed_guid, factory_id) = data.get_box_data(guid)
 568                                     netrefs.setdefault((testbed_guid, guid), set()).add(name)
 569
 570     def _create_testbed_controller(self, guid, data, element_guids, recover):
 571         (testbed_id, testbed_version) = data.get_testbed_data(guid)
 572         access_config = None if guid not in self._access_config else\
 573                 self._access_config[guid]
 574
 575         if recover and access_config is None:
 576             # need to create one
 577             access_config = self._access_config[guid] = proxy.AccessConfiguration()
 578         if access_config is not None:
 579             # force recovery mode
 580             access_config.set_attribute_value("recover",recover)
 581
 582         testbed = proxy.create_testbed_controller(testbed_id,
 583                 testbed_version, access_config)
 584         for (name, value) in data.get_attribute_data(guid):
 585             testbed.defer_configure(name, value)
 586         self._testbeds[guid] = testbed
 587
 588     def _program_testbed_controllers(self, element_guids, data):
 589         for guid in element_guids:
 590             (testbed_guid, factory_id) = data.get_box_data(guid)
 591             testbed = self._testbeds[testbed_guid]
 592             testbed.defer_create(guid, factory_id)
 593             for (name, value) in data.get_attribute_data(guid):
 594                 testbed.defer_create_set(guid, name, value)
 595
 596         for guid in element_guids:
 597             (testbed_guid, factory_id) = data.get_box_data(guid)
 598             testbed = self._testbeds[testbed_guid]
 599             for (connector_type_name, cross_guid, cross_connector_type_name) \
 600                     in data.get_connection_data(guid):
 601                 (testbed_guid, factory_id) = data.get_box_data(guid)
 602                 (cross_testbed_guid, cross_factory_id) = data.get_box_data(
 603                         cross_guid)
 604                 if testbed_guid == cross_testbed_guid:
 605                     testbed.defer_connect(guid, connector_type_name,
 606                             cross_guid, cross_connector_type_name)
 607                 else:
 608                     testbed.defer_cross_connect(guid, connector_type_name, cross_guid,
 609                             cross_testbed_id, cross_factory_id,
 610                             cross_connector_type_name)
 611                     # save cross data for later
 612                     self._add_crossdata(testbed_guid, guid, cross_testbed_guid,
 613                             cross_guid)
 614             for trace_id in data.get_trace_data(guid):
 615                 testbed.defer_add_trace(guid, trace_id)
 616             for (autoconf, address, netprefix, broadcast) in \
 617                     data.get_address_data(guid):
 618                 if address != None:
 619                     testbed.defer_add_address(guid, address, netprefix,
 620                             broadcast)
 621             for (destination, netprefix, nexthop) in data.get_route_data(guid):
 622                 testbed.defer_add_route(guid, destination, netprefix, nexthop)
 623
 624     def _add_crossdata(self, testbed_guid, guid, cross_testbed_guid, cross_guid):
 625         if testbed_guid not in self._crossdata:
 626             self._cross_data[testbed_guid] = dict()
 627         if cross_testbed_guid not in self._cross_data[testbed_guid]:
 628             self._cross_data[testbed_guid][cross_testbed_guid] = list()
 629         if cross_testbed_guid not in self._cross_data:
 630             self._cross_data[cross_testbed_guid] = dict()
 631         if testbed_guid not in self._cross_data[cross_testbed_guid]:
 632             self._cross_data[cross_testbed_guid][testbed_guid] = list()
 633         self._cross_data[testbed_guid][cross_testbed_guid].append(cross_guid)
 634         self._cross_data[cross_testbed_guid][testbed_guid].append(guid)
 635
 636     def _get_cross_data(self, testbed_guid):
 637         cross_data = dict()
 638         if not testbed_guid in self._cross_data:
 639             return cross_data
 640         for cross_testbed_guid, guid_list in self._cross_data[testbed_guid]:
 641             cross_data[cross_testbed_guid] = dict()
 642             cross_testbed = self._testbeds[cross_testbed_guid]
 643             for cross_guid in guid_list:
 644                 cross_data_guid = dict()
 645                 cross_data[cross_testbed_guid][cross_guid] = cross_data_guid
 646                 attributes_list = cross_testbed.get_attribute_list(cross_guid)
 647                 for attr_name in attributes_list:
 648                     attr_value = cross_testbed.get(TIME_NOW, cross_guid,
 649                             attr_name)
 650                     cross_data_guid[attr_name] = attr_value
 651         return cross_data
 652