Source Code for Module Products.ZenModel.ZenPackPersistence

  1  ########################################################################### 
  2  # 
  3  # This program is part of Zenoss Core, an open source monitoring platform. 
  4  # Copyright (C) 2008, Zenoss Inc. 
  5  # 
  6  # This program is free software; you can redistribute it and/or modify it 
  7  # under the terms of the GNU General Public License version 2 as published by 
  8  # the Free Software Foundation. 
  9  # 
 10  # For complete information please visit: http://www.zenoss.com/oss/ 
 11  # 
 12  ########################################################################### 
 13   
 14  __doc__=''' 
 15  ZenPackPersistence 
 16  ''' 
 17   
 18  from zope.interface import implements 
 19  from Products.ZenModel.interfaces import IIndexed 
 20   
 21  ZENPACK_PERSISTENCE_CATALOG = 'zenPackPersistence' 
 22   
 23  import logging 
 24  log = logging.getLogger('ZenPackPersistence') 
 25   
 26 -def CreateZenPackPersistenceCatalog(dmd): 
 27      ''' 
 28      Create the zenPackPersistence catalog if it does not exist. 
 29      Return the catalog 
 30      ''' 
 31      from Products.ZCatalog.ZCatalog import manage_addZCatalog 
 32      from Products.ZenUtils.Search import makeCaseSensitiveFieldIndex 
 33      zcat = getattr(dmd, ZENPACK_PERSISTENCE_CATALOG, None) 
 34      if zcat is None: 
 35          manage_addZCatalog(dmd, ZENPACK_PERSISTENCE_CATALOG, 
 36                                  ZENPACK_PERSISTENCE_CATALOG) 
 37          zcat = dmd._getOb(ZENPACK_PERSISTENCE_CATALOG) 
 38          cat = zcat._catalog 
 39          cat.addIndex('getZenPackName',makeCaseSensitiveFieldIndex('getZenPackName')) 
 40          cat.addColumn('id') 
 41          cat.addColumn('getPrimaryId') 
 42      return zcat 
 43   
 44   
 45 -def GetCatalogedObjects(dmd, packName): 
 46      """ 
 47      Return a list of all the objects in the zenPackPersistence catalog 
 48      for the given zenPack name. 
 49      If the catalog is not found, return None. 
 50      """ 
 51      zcat = getattr(dmd, ZENPACK_PERSISTENCE_CATALOG, None) 
 52      if zcat is None: 
 53          result = None 
 54      else: 
 55          result = [] 
 56          brains = zcat(dict(getZenPackName=packName)) 
 57          for brain in brains: 
 58              try: 
 59                  obj = brain.getObject() 
 60                  result.append(obj) 
 61              except KeyError, e: 
 62                  log.warn('catalog object %s not found in system', e) 
 63      return result 
 64   
 65   
 66 -class ZenPackPersistence(object): 
 67      ''' 
 68      This is a mix-in class that should be used whenever a ZenPack-supplied 
 69      class is going to be stored persistently in the zodb.  It provides 
 70      for a catalog to associate objects in zodb with the ZenPacks that provide 
 71      those objects' classes. 
 72       
 73      The motivation for this is that we usually need to delete all instances 
 74      of zenpack-supplied classes when that zenpack is deleted.  This is 
 75      because the class for those objects no longer exists and they are just 
 76      sad, broken, unloved objects in the zodb at that point.  This is  
 77      undesirable. 
 78       
 79      IMPORTANT: This should be the first class listed in any subclasses's 
 80      list of parents.  Otherwise the manage_* methods of the other classes 
 81      will likely be called and these skipped. 
 82      ''' 
 83      implements(IIndexed) 
 84   
 85      # Subclasses should set this to the id of the ZenPack or they 
 86      # should override getZenPackName() 
 87      # ZENPACKID = 'ZenPacks.my.name' 
 88   
 89 -    def getZenPackName(self): 
 90          ''' 
 91          ''' 
 92          if not self.ZENPACKID: 
 93              from ZenPack import ZenPackException 
 94              raise ZenPackException('The class %s must define ZENPACKID ' % 
 95                      str(self.__class__) + 
 96                      'or override getZenPackName().') 
 97          # Should we check to make sure ZENPACKID matches the name of an 
 98          # installed ZenPack? 
 99          return self.ZENPACKID 
100   
101   
102 -    def getZenPack(self, context): 
103          """ 
104          Return the ZenPack instance that provides this object. 
105          """ 
106          return context.dmd.ZenPackManager.packs._getOb( 
107                                              self.getZenPackName(), None) 
108       
109       
110 -    def path(self, *parts): 
111          """ 
112          Return the path to the installed ZenPack directory or a subdirectory. 
113          Example: zenpack.path('libexec') would return something like 
114          $ZENHOME/ZenPacks/ZenPacks.Me.MyZenPack/ZenPacks/Me/MyZenPack/libexec 
115          """ 
116          zp = self.getZenPack(self) 
117          return zp.path(*parts) 
118   
119   
120      # index_object and unindex_object are overridden so that instances 
121      # can participate in other catalogs, not just the  
122      # ZENPACK_PERSISTENCE_CATALOG. 
123      # If we used the standard method of just setting default_catalog in 
124      # this class then ZenPacks would not be able to override Zenoss 
125      # classes that already participate in catalogs, eg DeviceClass. 
126       
127 -    def index_object(self): 
128          """A common method to allow Findables to index themselves.""" 
129          cat = getattr(self, ZENPACK_PERSISTENCE_CATALOG, None) 
130          if cat is not None: 
131              cat.catalog_object(self, self.getPrimaryId())             
132          super(ZenPackPersistence, self).index_object() 
133   
134   
135 -    def unindex_object(self): 
136          """A common method to allow Findables to unindex themselves.""" 
137          #FIXME THIS WON'T WORK IF WE DELETE FROM THE ZENPACK PAGE BECAUSE WE CAN'T FIND THE CATALOG -EAD 
138          cat = getattr(self, ZENPACK_PERSISTENCE_CATALOG, None) 
139          if cat is not None: 
140              cat.uncatalog_object(self.getPrimaryId()) 
141          super(ZenPackPersistence, self).unindex_object() 
142