Source Code for Module ZenModel.RRDDataPointAlias

 1  ########################################################################### 
 2  # 
 3  # This program is part of Zenoss Core, an open source monitoring platform. 
 4  # Copyright (C) 2009, 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__="""RRDDataPointAlias 
15   
16  Create a simple level of indirection for normalization of data.  An alias is 
17  a pair of a name and an rpn formula.  The formula should convert the datapoint 
18  to the form represented by the name. 
19   
20  $Id:$""" 
21  import Globals 
22  from AccessControl import ClassSecurityInfo, Permissions 
23   
24  from Products.ZenUtils.ZenTales import talesEvalStr 
25  from Products.ZenRelations.RelSchema import ToOne, ToManyCont 
26  from Products.ZenModel.ZenModelRM import ZenModelRM 
27  from Products.ZenModel.ZenPackable import ZenPackable 
28   
29   
30  ALIAS_DELIMITER = ',' 
31  EVAL_KEY = '__EVAL:' 
32   
33 -def manage_addDataPointAlias( context, id, formula=None ): 
34      """ 
35      Add a datapoint alias to the datapoint given 
36      """ 
37      alias = RRDDataPointAlias( id ) 
38      alias.formula = formula 
39      context.aliases._setObject( id, alias ) 
40      return context.aliases._getOb( id ) 
41   
42 -class RRDDataPointAlias(ZenModelRM, ZenPackable): 
43       
44      meta_type = 'RRDDataPointAlias' 
45      formula = None 
46       
47      _properties = ( 
48          {'id':'formula', 'type':'string', 'mode':'w'}, 
49          ) 
50   
51      _relations = ZenPackable._relations + ( 
52          ("datapoint", ToOne(ToManyCont,"Products.ZenModel.RRDDataPoint","aliases")), 
53          ) 
54   
55   
56      # Screen action bindings (and tab definitions) 
57      factory_type_information = (  
58      {  
59          'immediate_view' : 'editRRDDataPoint', 
60          'actions'        : 
61          (  
62              { 'id'            : 'edit' 
63              , 'name'          : 'Data Point' 
64              , 'action'        : 'editRRDDataPoint' 
65              , 'permissions'   : ( Permissions.view, ) 
66              }, 
67          ) 
68      }, 
69      ) 
70   
71 -    def evaluate(self, context): 
72          """ 
73          Evaluate the formula with the given context so that the resulting 
74          rpn can be applied to the datapoint value.  There are two possible 
75          layers of evaluation: python and then TALES evaluation.  Both use the 
76          name 'here' to name the passed context.  See testRRDDataPointAlias for 
77          examples of usage. 
78          """ 
79          if self.formula: 
80              formula = self.formula 
81              if formula.startswith( EVAL_KEY ): 
82                  formula = formula[ len( EVAL_KEY ): ] 
83                  formula = str( eval( formula, { 'here' : context } ) )     
84              return talesEvalStr( formula, context )  
85          else: 
86              return None 
87