ActivityTool.py 41.7 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067
##############################################################################
#
# Copyright (c) 2002 Nexedi SARL and Contributors. All Rights Reserved.
#                    Jean-Paul Smets-Solanes <jp@nexedi.com>
#
# WARNING: This program as such is intended to be used by professional
# programmers who take the whole responsability of assessing all potential
# consequences resulting from its eventual inadequacies and bugs
# End users who are looking for a ready-to-use solution with commercial
# garantees and support are strongly adviced to contract a Free Software
# Service Company
#
# This program is Free Software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
#
##############################################################################

import socket
import urllib
import threading
import sys
from types import TupleType, StringType
import re

from Products.CMFCore import CMFCorePermissions
from Products.ERP5Type.Core.Folder import Folder
from Products.CMFActivity.ActiveResult import ActiveResult
from Products.PythonScripts.Utility import allow_class
from AccessControl import ClassSecurityInfo, Permissions
from AccessControl.SecurityManagement import newSecurityManager
from AccessControl.SecurityManagement import noSecurityManager
from AccessControl.SecurityManagement import setSecurityManager
from AccessControl.SecurityManagement import getSecurityManager
from Products.CMFCore.utils import UniqueObject, _getAuthenticatedUser, getToolByName
from Globals import InitializeClass, DTMLFile
from Acquisition import aq_base
from Acquisition import aq_inner
from Products.CMFActivity.ActiveObject import DISTRIBUTABLE_STATE, INVOKE_ERROR_STATE, VALIDATE_ERROR_STATE
from ActivityBuffer import ActivityBuffer
from zExceptions import ExceptionFormatter
from BTrees.OIBTree import OIBTree

from ZODB.POSException import ConflictError
from Products.MailHost.MailHost import MailHostError

from zLOG import LOG, INFO, WARNING

try:
  from Products.TimerService import getTimerService
except ImportError:
  def getTimerService(self):
    pass

# minimal IP:Port regexp
NODE_RE = re.compile('^\d+\.\d+\.\d+\.\d+:\d+$')

# Using a RAM property (not a property of an instance) allows
# to prevent from storing a state in the ZODB (and allows to restart...)
active_threads = 0
max_active_threads = 1 # 2 will cause more bug to appear (he he)
is_initialized = 0
tic_lock = threading.Lock() # A RAM based lock to prevent too many concurrent tic() calls
timerservice_lock = threading.Lock() # A RAM based lock to prevent TimerService spamming when busy
first_run = 1
currentNode = None
ROLE_IDLE = 0
ROLE_PROCESSING = 1

# Activity Registration
activity_dict = {}
activity_list = []

# Here go ActivityBuffer instances
# Structure:
#  global_activity_buffer[activity_tool_path][thread_id] = ActivityBuffer
global_activity_buffer = {}
from thread import get_ident, allocate_lock
global_activity_buffer_lock = allocate_lock()

def registerActivity(activity):
  # Must be rewritten to register
  # class and create instance for each activity
  #LOG('Init Activity', 0, str(activity.__name__))
  activity_instance = activity()
  activity_list.append(activity_instance)
  activity_dict[activity.__name__] = activity_instance

class Message:
  """Activity Message Class.

  Message instances are stored in an activity queue, inside the Activity Tool.
  """
  def __init__(self, obj, active_process, activity_kw, method_id, args, kw):
    if isinstance(obj, str):
      self.object_path = tuple(obj.split('/'))
    else:
      self.object_path = obj.getPhysicalPath()
    if type(active_process) is StringType:
      self.active_process = active_process.split('/')
    elif active_process is None:
      self.active_process = None
    else:
      self.active_process = active_process.getPhysicalPath()
      self.active_process_uid = active_process.getUid()
    self.activity_kw = activity_kw
    self.method_id = method_id
    self.args = args
    self.kw = kw
    self.is_executed = 0
    self.exc_type = None
    self.exc_value = None
    self.traceback = None
    self.processing = None
    self.user_name = str(_getAuthenticatedUser(self))
    # Store REQUEST Info ?

  def getObject(self, activity_tool):
    """return the object referenced in this message."""
    return activity_tool.unrestrictedTraverse(self.object_path)

  def getObjectList(self, activity_tool):
    """return the list of object that can be expanded from this message."""
    object_list = []
    try:
      object_list.append(self.getObject(activity_tool))
    except KeyError:
      pass
    else:
      if self.hasExpandMethod():
        expand_method_id = self.activity_kw['expand_method_id']
        # FIXME: how to pass parameters?
        object_list = getattr(object_list[0], expand_method_id)()
    return object_list

  def hasExpandMethod(self):
    """return true if the message has an expand method.
    An expand method is used to expand the list of objects and to turn a
    big recursive transaction affecting many objects into multiple
    transactions affecting only one object at a time (this can prevent
    duplicated method calls)."""
    return self.activity_kw.has_key('expand_method_id')

  def changeUser(self, user_name, activity_tool):
    """restore the security context for the calling user."""
    uf = activity_tool.getPortalObject().acl_users
    user = uf.getUserById(user_name)
    # if the user is not found, try to get it from a parent acl_users
    # XXX this is still far from perfect, because we need to store all
    # informations about the user (like original user folder, roles) to
    # replay the activity with exactly the same security context as if
    # it had been executed without activity.
    if user is None:
      uf = activity_tool.getPortalObject().aq_parent.acl_users
      user = uf.getUserById(user_name)
    if user is not None:
      user = user.__of__(uf)
      newSecurityManager(None, user)
    else :
      LOG("CMFActivity", WARNING,
          "Unable to find user %s in the portal" % user_name)
      noSecurityManager()
    return user

  def activateResult(self, activity_tool, result, object):
    if self.active_process is not None:
      active_process = activity_tool.unrestrictedTraverse(self.active_process)
      if isinstance(result,ActiveResult):
        result.edit(object_path=object)
        result.edit(method_id=self.method_id)
        # XXX Allow other method_id in future
        active_process.activateResult(result)
      else:
        active_process.activateResult(
                    ActiveResult(object_path=object,
                          method_id=self.method_id,
                          result=result)) # XXX Allow other method_id in future

  def __call__(self, activity_tool):
    try:
      obj = self.getObject(activity_tool)
      old_security_manager = getSecurityManager()
      # Change user if required (TO BE DONE)
      # We will change the user only in order to execute this method
      user = self.changeUser(self.user_name, activity_tool)
      try:
        result = getattr(obj, self.method_id)(*self.args, **self.kw)
      finally:
        setSecurityManager(old_security_manager)

      self.activateResult(activity_tool, result, obj)
      self.is_executed = 1
    except:
      self.is_executed = 0
      self.exc_type = sys.exc_info()[0]
      self.exc_value = str(sys.exc_info()[1])
      self.traceback = ''.join(ExceptionFormatter.format_exception(
                               *sys.exc_info()))
      LOG('ActivityTool', WARNING,
          'Could not call method %s on object %s' % (
          self.method_id, self.object_path), error=sys.exc_info())
      # push the error in ZODB error_log
      if getattr(activity_tool, 'error_log', None) is not None:
        activity_tool.error_log.raising(sys.exc_info())

  def validate(self, activity, activity_tool, check_order_validation=1):
    return activity.validate(activity_tool, self,
                             check_order_validation=check_order_validation,
                             **self.activity_kw)

  def getDependentMessageList(self, activity, activity_tool):
    return activity.getDependentMessageList(activity_tool, self, **self.activity_kw)

  def notifyUser(self, activity_tool, message="Failed Processing Activity"):
    """Notify the user that the activity failed."""
    portal = activity_tool.getPortalObject()
    user_email = None
    user = portal.portal_membership.getMemberById(self.user_name)
    if user is not None:
      user_email = user.getProperty('email')
    if user_email in ('', None):
      user_email = portal.getProperty('email_to_address',
                       portal.getProperty('email_from_address'))
    mail_text = """From: %s
To: %s
Subject: %s

%s

Document: %s
Method: %s
Exception: %s %s

%s
""" % (activity_tool.email_from_address, user_email, message,
       message, '/'.join(self.object_path), self.method_id,
       self.exc_type, self.exc_value, self.traceback)
    try:
      activity_tool.MailHost.send( mail_text )
    except (socket.error, MailHostError), message:
      LOG('ActivityTool.notifyUser', WARNING, 'Mail containing failure information failed to be sent: %s. Exception was: %s %s\n%s' % (message, self.exc_type, self.exc_value, self.traceback))

  def reactivate(self, activity_tool):
    # Reactivate the original object.
    obj= self.getObject(activity_tool)
    # Change user if required (TO BE DONE)
    # We will change the user only in order to execute this method
    current_user = str(_getAuthenticatedUser(self))
    user = self.changeUser(self.user_name, activity_tool)
    try:
      active_obj = obj.activate(**self.activity_kw)
      getattr(active_obj, self.method_id)(*self.args, **self.kw)
    finally:
      # Use again the previous user
      if user is not None:
        self.changeUser(current_user, activity_tool)

class Method:

  def __init__(self, passive_self, activity, active_process, kw, method_id):
    self.__passive_self = passive_self
    self.__activity = activity
    self.__active_process = active_process
    self.__kw = kw
    self.__method_id = method_id

  def __call__(self, *args, **kw):
    m = Message(self.__passive_self, self.__active_process, self.__kw, self.__method_id, args, kw)
    activity_dict[self.__activity].queueMessage(self.__passive_self.portal_activities, m)

allow_class(Method)

class ActiveWrapper:

  def __init__(self, passive_self, activity, active_process, **kw):
    self.__dict__['__passive_self'] = passive_self
    self.__dict__['__activity'] = activity
    self.__dict__['__active_process'] = active_process
    self.__dict__['__kw'] = kw

  def __getattr__(self, id):
    return Method(self.__dict__['__passive_self'], self.__dict__['__activity'],
                  self.__dict__['__active_process'],
                  self.__dict__['__kw'], id)

class ActivityTool (Folder, UniqueObject):
    """
    ActivityTool is the central point for activity management.

    Improvement to consider to reduce locks:

      Idea 1: create an SQL tool which accumulate queries and executes them at the end of a transaction,
              thus allowing all SQL transaction to happen in a very short time
              (this would also be a great way of using MyISAM tables)

      Idea 2: do the same at the level of ActivityTool

      Idea 3: do the same at the level of each activity (ie. queueMessage
              accumulates and fires messages at the end of the transactino)
    """
    id = 'portal_activities'
    meta_type = 'CMF Activity Tool'
    portal_type = 'Activity Tool'
    allowed_types = ( 'CMF Active Process', )
    security = ClassSecurityInfo()

    manage_options = tuple(
                     [ { 'label' : 'Overview', 'action' : 'manage_overview' }
                     , { 'label' : 'Activities', 'action' : 'manageActivities' }
                     , { 'label' : 'LoadBalancing', 'action' : 'manageLoadBalancing'}
                     , { 'label' : 'Advanced', 'action' : 'manageActivitiesAdvanced' }
                     ,
                     ] + list(Folder.manage_options))

    security.declareProtected( CMFCorePermissions.ManagePortal , 'manageActivities' )
    manageActivities = DTMLFile( 'dtml/manageActivities', globals() )

    security.declareProtected( CMFCorePermissions.ManagePortal , 'manageActivitiesAdvanced' )
    manageActivitiesAdvanced = DTMLFile( 'dtml/manageActivitiesAdvanced', globals() )

    security.declareProtected( CMFCorePermissions.ManagePortal , 'manage_overview' )
    manage_overview = DTMLFile( 'dtml/explainActivityTool', globals() )
    
    security.declareProtected( CMFCorePermissions.ManagePortal , 'manageLoadBalancing' )
    manageLoadBalancing = DTMLFile( 'dtml/manageLoadBalancing', globals() )
    
    distributingNode = ''
    _nodes = ()

    def __init__(self):
        return Folder.__init__(self, ActivityTool.id)

    # Filter content (ZMI))
    def filtered_meta_types(self, user=None):
        # Filters the list of available meta types.
        all = ActivityTool.inheritedAttribute('filtered_meta_types')(self)
        meta_types = []
        for meta_type in self.all_meta_types():
            if meta_type['name'] in self.allowed_types:
                meta_types.append(meta_type)
        return meta_types

    def initialize(self):
      global is_initialized
      from Activity import RAMQueue, RAMDict, SQLQueue, SQLDict
      # Initialize each queue
      for activity in activity_list:
        activity.initialize(self)
      is_initialized = 1
      
    security.declareProtected(Permissions.manage_properties, 'isSubscribed')
    def isSubscribed(self):
        """
        return True, if we are subscribed to TimerService.
        Otherwise return False.
        """
        service = getTimerService(self)
        if not service:
            LOG('ActivityTool', INFO, 'TimerService not available')
            return False
        
        path = '/'.join(self.getPhysicalPath())
        if path in service.lisSubscriptions():
            return True
        return False

    security.declareProtected(Permissions.manage_properties, 'subscribe')
    def subscribe(self, REQUEST=None, RESPONSE=None):
        """ subscribe to the global Timer Service """
        service = getTimerService(self)
        url = '%s/manageLoadBalancing?manage_tabs_message=' %self.absolute_url()
        if not service:
            LOG('ActivityTool', INFO, 'TimerService not available')
            url += urllib.quote('TimerService not available')
        else:
            service.subscribe(self)
            url += urllib.quote("Subscribed to Timer Service")
        if RESPONSE is not None:
            RESPONSE.redirect(url)

    security.declareProtected(Permissions.manage_properties, 'unsubscribe')
    def unsubscribe(self, REQUEST=None, RESPONSE=None):
        """ unsubscribe from the global Timer Service """
        service = getTimerService(self)
        url = '%s/manageLoadBalancing?manage_tabs_message=' %self.absolute_url()
        if not service:
            LOG('ActivityTool', INFO, 'TimerService not available')
            url += urllib.quote('TimerService not available')
        else:
            service.unsubscribe(self)
            url += urllib.quote("Unsubscribed from Timer Service")
        if RESPONSE is not None:
            RESPONSE.redirect(url)

    def manage_beforeDelete(self, item, container):
        self.unsubscribe()
        Folder.inheritedAttribute('manage_beforeDelete')(self, item, container)
    
    def manage_afterAdd(self, item, container):
        self.subscribe()
        Folder.inheritedAttribute('manage_afterAdd')(self, item, container)
       
    def getCurrentNode(self):
        """ Return current node in form ip:port """
        global currentNode
        if currentNode is None:
          port = ''
          from asyncore import socket_map
          for k, v in socket_map.items():
              if hasattr(v, 'port'):
                  # see Zope/lib/python/App/ApplicationManager.py: def getServers(self)
                  type = str(getattr(v, '__class__', 'unknown'))
                  if type == 'ZServer.HTTPServer.zhttp_server':
                      port = v.port
                      break
          ip = socket.gethostbyname(socket.gethostname())
          currentNode = '%s:%s' %(ip, port)
        return currentNode
        
    security.declarePublic('getDistributingNode')
    def getDistributingNode(self):
        """ Return the distributingNode """
        return self.distributingNode

    def getNodeList(self, role=None):
      node_dict = self.getNodeDict()
      if role is None:
        result = [x for x in node_dict.keys()]
      else:
        result = [node_id for node_id, node_role in node_dict.items() if node_role == role]
      result.sort()
      return result

    def getNodeDict(self):
      nodes = self._nodes
      if isinstance(nodes, tuple):
        new_nodes = OIBTree()
        new_nodes.update([(x, ROLE_PROCESSING) for x in self._nodes])
        self._nodes = nodes = new_nodes
      return nodes

    def registerNode(self, node):
      node_dict = self.getNodeDict()
      if not node_dict.has_key(node):
        if len(node_dict) == 0: # If we are registering the first node, make
                                # it both the distributing node and a processing
                                # node.
          role = ROLE_PROCESSING
          self.distributingNode = node
        else:
          role = ROLE_IDLE
        self.updateNode(node, role)

    def updateNode(self, node, role):
      node_dict = self.getNodeDict()
      node_dict[node] = role

    security.declareProtected(CMFCorePermissions.ManagePortal, 'getProcessingNodeList')
    def getProcessingNodeList(self):
      return self.getNodeList(role=ROLE_PROCESSING)

    security.declareProtected(CMFCorePermissions.ManagePortal, 'getIdleNodeList')
    def getIdleNodeList(self):
      return self.getNodeList(role=ROLE_IDLE)

    def _isValidNodeName(self, node_name) :
      """Check we have been provided a good node name"""
      return isinstance(node_name, str) and NODE_RE.match(node_name)
      
    security.declarePublic('manage_setDistributingNode')
    def manage_setDistributingNode(self, distributingNode, REQUEST=None):
        """ set the distributing node """   
        if not distributingNode or self._isValidNodeName(distributingNode):
          self.distributingNode = distributingNode
          if REQUEST is not None:
              REQUEST.RESPONSE.redirect(
                  REQUEST.URL1 +
                  '/manageLoadBalancing?manage_tabs_message=' +
                  urllib.quote("Distributing Node successfully changed."))
        else :
          if REQUEST is not None:
              REQUEST.RESPONSE.redirect(
                  REQUEST.URL1 +
                  '/manageLoadBalancing?manage_tabs_message=' +
                  urllib.quote("Malformed Distributing Node."))

    security.declareProtected(CMFCorePermissions.ManagePortal, 'manage_delNode')
    def manage_delNode(self, unused_node_list=None, REQUEST=None):
      """ delete selected unused nodes """
      processing_node = self.getDistributingNode()
      updated_processing_node = False
      if unused_node_list is not None:
        node_dict = self.getNodeDict()
        for node in unused_node_list:
          if node in node_dict:
            del node_dict[node]
          if node == processing_node:
            self.processing_node = ''
            updated_processing_node = True
      if REQUEST is not None:
        if unused_node_list is None:
          message = "No unused node selected, nothing deleted."
        else:
          message = "Deleted nodes %r." % (unused_node_list, )
        if updated_processing_node:
          message += "Disabled distributing node because it was deleted."
        REQUEST.RESPONSE.redirect(
          REQUEST.URL1 +
          '/manageLoadBalancing?manage_tabs_message=' +
          urllib.quote(message))

    security.declareProtected(CMFCorePermissions.ManagePortal, 'manage_addToProcessingList')
    def manage_addToProcessingList(self, unused_node_list=None, REQUEST=None):
      """ Change one or more idle nodes into processing nodes """
      if unused_node_list is not None:
        node_dict = self.getNodeDict()
        for node in unused_node_list:
          self.updateNode(node, ROLE_PROCESSING)
      if REQUEST is not None:
        if unused_node_list is None:
          message = "No unused node selected, nothing done."
        else:
          message = "Nodes now procesing: %r." % (unused_node_list, )
        REQUEST.RESPONSE.redirect(
          REQUEST.URL1 +
          '/manageLoadBalancing?manage_tabs_message=' +
          urllib.quote(message))

    security.declareProtected(CMFCorePermissions.ManagePortal, 'manage_removeFromProcessingList')
    def manage_removeFromProcessingList(self, processing_node_list=None, REQUEST=None):
      """ Change one or more procesing nodes into idle nodes """
      if processing_node_list is not None:
        node_dict = self.getNodeDict()
        for node in processing_node_list:
          self.updateNode(node, ROLE_IDLE)
      if REQUEST is not None:
        if processing_node_list is None:
          message = "No used node selected, nothing done."
        else:
          message = "Nodes now unused %r." % (processing_node_list, )
        REQUEST.RESPONSE.redirect(
          REQUEST.URL1 +
          '/manageLoadBalancing?manage_tabs_message=' +
          urllib.quote(message))

    def process_timer(self, tick, interval, prev="", next=""):
        """
        Call distribute() if we are the Distributing Node and call tic()
        with our node number.
        This method is called by TimerService in the interval given
        in zope.conf. The Default is every 5 seconds.
        """
        # Prevent TimerService from starting multiple threads in parallel
        acquired = timerservice_lock.acquire(0)
        if not acquired:
          return

        old_sm = getSecurityManager()
        try:
          # get owner of portal_catalog, so normally we should be able to
          # have the permission to invoke all activities
          user = self.portal_catalog.getWrappedOwner()
          newSecurityManager(self.REQUEST, user)

          currentNode = self.getCurrentNode()
          self.registerNode(currentNode)
          processing_node_list = self.getNodeList(role=ROLE_PROCESSING)

          # only distribute when we are the distributingNode or if it's empty
          if (self.getDistributingNode() == currentNode):
            self.distribute(len(processing_node_list))

          # SkinsTool uses a REQUEST cache to store skin objects, as
          # with TimerService we have the same REQUEST over multiple
          # portals, we clear this cache to make sure the cache doesn't
          # contains skins from another portal.
          stool = getToolByName(self, 'portal_skins', None)
          if stool is not None:
            stool.changeSkin(None)

          # call tic for the current processing_node
          # the processing_node numbers are the indices of the elements in the node tuple +1
          # because processing_node starts form 1
          if currentNode in processing_node_list:
            self.tic(processing_node_list.index(currentNode)+1)
        except:
          # Catch ALL exception to avoid killing timerserver.
          LOG('ActivityTool', ERROR, 'process_timer received an exception', error=sys.exc_info())
        finally:
          timerservice_lock.release()
          setSecurityManager(old_sm)

    security.declarePublic('distribute')
    def distribute(self, node_count=1):
      """
        Distribute load
      """
      # Initialize if needed
      global is_initialized
      if not is_initialized: self.initialize()

      # Call distribute on each queue
      for activity in activity_list:
        activity.distribute(aq_inner(self), node_count)

    security.declarePublic('tic')
    def tic(self, processing_node=1, force=0):
      """
        Starts again an activity
        processing_node starts from 1 (there is not node 0)
      """
      global active_threads, is_initialized, first_run

      # return if the number of threads is too high
      # else, increase the number of active_threads and continue
      tic_lock.acquire()
      too_many_threads = (active_threads >= max_active_threads)
      if not too_many_threads or force:
        active_threads += 1
      else:
        tic_lock.release()
        raise RuntimeError, 'Too many threads'
      tic_lock.release()

      # Initialize if needed
      if not is_initialized: self.initialize()

      inner_self = aq_inner(self)

      # If this is the first tic after zope is started, reset the processing
      # flag for activities of this node
      if first_run:
        inner_self.SQLDict_clearProcessingFlag(
                                processing_node=processing_node)
        inner_self.SQLQueue_clearProcessingFlag(
                                processing_node=processing_node)
        first_run = 0

      try:
        # Wakeup each queue
        for activity in activity_list:
          activity.wakeup(inner_self, processing_node)

        # Process messages on each queue in round robin
        has_awake_activity = 1
        while has_awake_activity:
          has_awake_activity = 0
          for activity in activity_list:
            activity.tic(inner_self, processing_node) # Transaction processing is the responsability of the activity
            has_awake_activity = has_awake_activity or activity.isAwake(inner_self, processing_node)
      finally:
        # decrease the number of active_threads
        tic_lock.acquire()
        active_threads -= 1
        tic_lock.release()

    def hasActivity(self, *args, **kw):
      # Check in each queue if the object has deferred tasks
      # if not argument is provided, then check on self
      if len(args) > 0:
        obj = args[0]
      else:
        obj = self
      for activity in activity_list:
        if activity.hasActivity(aq_inner(self), obj, **kw):
          return 1
      return 0

    def getActivityBuffer(self, create_if_not_found=True):
      """
        Get activtity buffer for this thread for this activity tool.
        If no activity buffer is found at lowest level and create_if_not_found
        is True, create one.
        Intermediate level is unconditionaly created if non existant because
        chances are it will be used in the instance life.
        Lock is held when checking for intermediate level existance
        because:
         - intermediate level dict must not be created in 2 threads at the
           same time, since one creation would destroy the existing one.
        It's released after that step because:
         - lower level access is at thread scope, thus by definition there
           can be only one access at a time to a key
         - GIL protects us when accessing python instances
      """
      global global_activity_buffer
      global global_activity_buffer_lock
      assert getattr(self, 'aq_self', None) is not None
      my_instance_key = self.getPhysicalPath()
      my_thread_key = get_ident()
      global_activity_buffer_lock.acquire()
      try:
        if my_instance_key not in global_activity_buffer:
          global_activity_buffer[my_instance_key] = {}
      finally:
        global_activity_buffer_lock.release()
      thread_activity_buffer = global_activity_buffer[my_instance_key]
      if my_thread_key not in thread_activity_buffer:
        if create_if_not_found:
          buffer = ActivityBuffer(activity_tool=self)
        else:
          buffer = None
        thread_activity_buffer[my_thread_key] = buffer
      activity_buffer = thread_activity_buffer[my_thread_key]
      return activity_buffer

    security.declarePrivate('activateObject')
    def activateObject(self, object, activity, active_process, **kw):
      global is_initialized
      if not is_initialized: self.initialize()
      self.getActivityBuffer()
      return ActiveWrapper(object, activity, active_process, **kw)

    def deferredQueueMessage(self, activity, message):
      activity_buffer = self.getActivityBuffer()
      activity_buffer.deferredQueueMessage(self, activity, message)

    def deferredDeleteMessage(self, activity, message):
      activity_buffer = self.getActivityBuffer()
      activity_buffer.deferredDeleteMessage(self, activity, message)

    def getRegisteredMessageList(self, activity):
      activity_buffer = self.getActivityBuffer(create_if_not_found=False)
      if activity_buffer is not None:
        #activity_buffer._register() # This is required if flush flush is called outside activate
        return activity.getRegisteredMessageList(activity_buffer,
                                                 aq_inner(self))
      else:
        return []

    def unregisterMessage(self, activity, message):
      activity_buffer = self.getActivityBuffer()
      #activity_buffer._register()
      return activity.unregisterMessage(activity_buffer, aq_inner(self), message)

    def flush(self, obj, invoke=0, **kw):
      global is_initialized
      if not is_initialized: self.initialize()
      self.getActivityBuffer()
      if isinstance(obj, tuple):
        object_path = obj
      else:
        object_path = obj.getPhysicalPath()
      for activity in activity_list:
        activity.flush(aq_inner(self), object_path, invoke=invoke, **kw)

    def start(self, **kw):
      global is_initialized
      if not is_initialized: self.initialize()
      for activity in activity_list:
        activity.start(aq_inner(self), **kw)

    def stop(self, **kw):
      global is_initialized
      if not is_initialized: self.initialize()
      for activity in activity_list:
        activity.stop(aq_inner(self), **kw)

    def invoke(self, message):
      if getattr(self, 'aq_chain', None) is not None:
        # Grab existing acquisition chain and extrach base objects.
        base_chain = [aq_base(x) for x in self.aq_chain]
        # Grab existig request (last chain item) and create a copy.
        request_container = base_chain.pop()
        request = request_container.REQUEST
        # XXX: REQUEST.clone() requires PARENTS to be set, and it's not when
        # runing unit tests. Recreate it if it does not exist.
        parents = getattr(request, 'PARENTS', None)
        if parents is None:
          LOG('CMFActivity.ActivityTool.invoke', INFO, 'PARENTS is not defined in REQUEST. It should only happen in unit tests.')
          request['PARENTS'] = self.aq_chain[:]
        new_request_container = request_container.__class__(REQUEST=request.clone())
        # Recreate acquisition chain.
        my_self = new_request_container
        base_chain.reverse()
        for item in base_chain:
          my_self = item.__of__(my_self)
      else:
        my_self = self
        LOG('CMFActivity.ActivityTool.invoke', INFO, 'Strange: invoke is called outside of acquisition context.')
      message(my_self)

    def invokeGroup(self, method_id, message_list):
      # Invoke a group method.
      object_list = []
      expanded_object_list = []
      new_message_list = []
      path_dict = {}
      # Filter the list of messages. If an object is not available, ignore such a message.
      # In addition, expand an object if necessary, and make sure that no duplication happens.
      for m in message_list:
        # alternate method is used to segregate objects which cannot be grouped.
        alternate_method_id = m.activity_kw.get('alternate_method_id')
        try:
          obj = m.getObject(self)
          i = len(new_message_list) # This is an index of this message in new_message_list.
          if m.hasExpandMethod():
            for subobj in m.getObjectList(self):
              path = subobj.getPath()
              if path not in path_dict:
                path_dict[path] = i
                if alternate_method_id is not None \
                   and hasattr(aq_base(subobj), alternate_method_id):
                  # if this object is alternated, generate a new single active object.
                  activity_kw = m.activity_kw.copy()
                  if 'group_method_id' in activity_kw:
                    del activity_kw['group_method_id']
                  if 'group_id' in activity_kw:
                    del activity_kw['group_id']                    
                  active_obj = subobj.activate(**activity_kw)
                  getattr(active_obj, alternate_method_id)(*m.args, **m.kw)
                else:
                  expanded_object_list.append(subobj)
          else:
            path = obj.getPath()
            if path not in path_dict:
              path_dict[path] = i
              if alternate_method_id is not None \
                  and hasattr(aq_base(obj), alternate_method_id):
                # if this object is alternated, generate a new single active object.
                activity_kw = m.activity_kw.copy()
                if 'group_method_id' in activity_kw:
                  del activity_kw['group_method_id']
                if 'group_id' in activity_kw:
                  del activity_kw['group_id']
                active_obj = obj.activate(**activity_kw)
                getattr(active_obj, alternate_method_id)(*m.args, **m.kw)
              else:
                expanded_object_list.append(obj)
          object_list.append(obj)
          new_message_list.append(m)
        except:
          m.is_executed = 0
          m.exc_type = sys.exc_info()[0]
          LOG('WARNING ActivityTool', 0,
              'Could not call method %s on object %s' %
              (m.method_id, m.object_path), error=sys.exc_info())

      try:
        if len(expanded_object_list) > 0:
          method = self.unrestrictedTraverse(method_id)
          # FIXME: how to apply security here?
          # NOTE: expanded_object_list must be set to failed objects by the callee.
          #       If it fully succeeds, expanded_object_list must be empty when returning.
          result = method(expanded_object_list, **m.kw)
        else:
          result = None
      except:
        # In this case, the group method completely failed.
        for m in new_message_list:
          m.is_executed = 0
          m.exc_type = sys.exc_info()[0]
        LOG('WARNING ActivityTool', 0,
            'Could not call method %s on objects %s' %
            (method_id, expanded_object_list), error=sys.exc_info())
      else:
        # Obtain all indices of failed messages. Note that this can be a partial failure.
        failed_message_dict = {}
        for obj in expanded_object_list:
          path = obj.getPath()
          i = path_dict[path]
          failed_message_dict[i] = None

        # Only for succeeded messages, an activity process is invoked (if any).
        for i in xrange(len(object_list)):
          object = object_list[i]
          m = new_message_list[i]
          if i in failed_message_dict:
            m.is_executed = 0
            LOG('ActivityTool', WARNING,
                'the method %s partially failed on object %s' %
                (m.method_id, m.object_path,))
          else:
            try:
              m.activateResult(self, result, object)
              m.is_executed = 1
            except:
              m.is_executed = 0
              m.exc_type = sys.exc_info()[0]
              LOG('ActivityTool', WARNING,
                  'Could not call method %s on object %s' % (
                  m.method_id, m.object_path), error=sys.exc_info())

    def newMessage(self, activity, path, active_process,
                   activity_kw, method_id, *args, **kw):
      # Some Security Cheking should be made here XXX
      global is_initialized
      if not is_initialized: self.initialize()
      self.getActivityBuffer()
      activity_dict[activity].queueMessage(aq_inner(self),
        Message(path, active_process, activity_kw, method_id, args, kw))

    security.declareProtected( CMFCorePermissions.ManagePortal, 'manageInvoke' )
    def manageInvoke(self, object_path, method_id, REQUEST=None):
      """
        Invokes all methods for object "object_path"
      """
      if type(object_path) is type(''):
        object_path = tuple(object_path.split('/'))
      self.flush(object_path,method_id=method_id,invoke=1)
      if REQUEST is not None:
        return REQUEST.RESPONSE.redirect('%s/%s' %
                (self.absolute_url(), 'manageActivities'))

    security.declareProtected( CMFCorePermissions.ManagePortal, 'manageCancel' )
    def manageCancel(self, object_path, method_id, REQUEST=None):
      """
        Cancel all methods for object "object_path"
      """
      if type(object_path) is type(''):
        object_path = tuple(object_path.split('/'))
      self.flush(object_path,method_id=method_id,invoke=0)
      if REQUEST is not None:
        return REQUEST.RESPONSE.redirect('%s/%s' %
                (self.absolute_url(), 'manageActivities'))

    security.declareProtected( CMFCorePermissions.ManagePortal,
                               'manageClearActivities' )
    def manageClearActivities(self, keep=1, REQUEST=None):
      """
        Clear all activities and recreate tables.
      """
      folder = getToolByName(self, 'portal_skins').activity

      # Obtain all pending messages.
      message_list = []
      if keep:
        for activity in activity_list:
          if hasattr(activity, 'dumpMessageList'):
            try:
              message_list.extend(activity.dumpMessageList(self))
            except ConflictError:
              raise
            except:
              LOG('ActivityTool', WARNING,
                  'could not dump messages from %s' %
                  (activity,), error=sys.exc_info())

      if getattr(folder, 'SQLDict_createMessageTable', None) is not None:
        try:
          folder.SQLDict_dropMessageTable()
        except ConflictError:
          raise
        except:
          LOG('CMFActivity', WARNING,
              'could not drop the message table',
              error=sys.exc_info())
        folder.SQLDict_createMessageTable()

      if getattr(folder, 'SQLQueue_createMessageTable', None) is not None:
        try:
          folder.SQLQueue_dropMessageTable()
        except ConflictError:
          raise
        except:
          LOG('CMFActivity', WARNING,
              'could not drop the message queue table',
              error=sys.exc_info())
        folder.SQLQueue_createMessageTable()

      # Reactivate the messages.
      for m in message_list:
        try:
          m.reactivate(aq_inner(self))
        except ConflictError:
          raise
        except:
          LOG('ActivityTool', WARNING,
              'could not reactivate the message %r, %r' %
              (m.object_path, m.method_id), error=sys.exc_info())

      if REQUEST is not None:
        return REQUEST.RESPONSE.redirect('%s/%s' % (self.absolute_url(),
          'manageActivitiesAdvanced?manage_tabs_message=Activities%20Cleared'))

    security.declarePublic('getMessageList')
    def getMessageList(self,**kw):
      """
        List messages waiting in queues
      """
      # Initialize if needed
      if not is_initialized: self.initialize()

      message_list = []
      for activity in activity_list:
        try:
          message_list += activity.getMessageList(aq_inner(self),**kw)
        except AttributeError:
          LOG('getMessageList, could not get message from Activity:',0,activity)
      return message_list

    security.declarePublic('countMessageWithTag')
    def countMessageWithTag(self, value):
      """
        Return the number of messages which match the given tag.
      """
      message_count = 0
      for activity in activity_list:
        message_count += activity.countMessageWithTag(aq_inner(self), value)
      return message_count

    security.declarePublic('countMessage')
    def countMessage(self, **kw):
      """
        Return the number of messages which match the given parameter.

        Parameters allowed:

        method_id : the id of the method
        path : for activities on a particular object
        tag : activities with a particular tag
        message_uid : activities with a particular uid
      """
      message_count = 0
      for activity in activity_list:
        message_count += activity.countMessage(aq_inner(self), **kw)
      return message_count

    security.declareProtected( CMFCorePermissions.ManagePortal , 'newActiveProcess' )
    def newActiveProcess(self, **kw):
      from ActiveProcess import addActiveProcess
      new_id = str(self.generateNewId())
      addActiveProcess(self, new_id)
      active_process = self._getOb(new_id)
      active_process.edit(**kw)
      return active_process

    def reindexObject(self):
      self.immediateReindexObject()

    # Active synchronisation methods
    security.declarePrivate('validateOrder')
    def validateOrder(self, message, validator_id, validation_value):
      message_list = self.getDependentMessageList(message, validator_id, validation_value)
      return len(message_list) > 0

    security.declarePrivate('getDependentMessageList')
    def getDependentMessageList(self, message, validator_id, validation_value):
      global is_initialized
      if not is_initialized: self.initialize()
      message_list = []
      method_id = "_validate_%s" % validator_id
      for activity in activity_list:
        method = getattr(activity, method_id, None)
        if method is not None:
          result = method(aq_inner(self), message, validation_value)
          if result:
            message_list.extend([(activity, m) for m in result])
      return message_list

    # Required for tests (time shift)
    def timeShift(self, delay):
      global is_initialized
      if not is_initialized: self.initialize()
      for activity in activity_list:
        activity.timeShift(aq_inner(self), delay)

InitializeClass(ActivityTool)