Open-ILS/src/python/oils/utils/idl.py

   1 """
   2 Parses an Evergreen fieldmapper IDL file and builds a global registry of
   3 objects representing that IDL.
   4
   5 Typical usage:
   6
   7 >>> import osrf.system
   8 >>> import oils.utils.idl
   9 >>> osrf.system.connect('/openils/conf/opensrf_core.xml', 'config.opensrf')
  10 >>> oils.utils.idl.oilsParseIDL()
  11 >>> # 'bre' is a network registry hint, or class ID in the IDL file
  12 ... print oils.utils.idl.oilsGetIDLParser().IDLObject['bre']['tablename']
  13 biblio.record_entry
  14 """
  15 import osrf.net_obj
  16 import osrf.log
  17 import osrf.set
  18
  19 import sys, string, xml.dom.minidom
  20 from oils.const import OILS_NS_OBJ, OILS_NS_PERSIST, OILS_NS_REPORTER
  21
  22 __global_parser = None
  23
  24 def oilsParseIDL():
  25     global __global_parser
  26     if __global_parser: return # no need to re-parse the IDL
  27     idlParser = oilsIDLParser();
  28     idlParser.setIDL(osrf.set.get('IDL'))
  29     idlParser.parseIDL()
  30     __global_parser = idlParser
  31
  32 def oilsGetIDLParser():
  33     global __global_parser
  34     return __global_parser
  35
  36 class oilsIDLParser(object):
  37
  38     def __init__(self):
  39         self.IDLObject = {}
  40
  41     def setIDL(self, file):
  42         osrf.log.log_info("setting IDL file to " + str(file))
  43         self.idlFile = file
  44
  45     def __getAttr(self, node, name, ns=None):
  46         """ Find the attribute value on a given node
  47             Namespace is ignored for now..
  48             not sure if minidom has namespace support.
  49             """
  50         attr = node.attributes.get(name)
  51         if attr:
  52             return attr.nodeValue
  53         return None
  54
  55     def parseIDL(self):
  56         """Parses the IDL file and builds class objects"""
  57
  58         doc = xml.dom.minidom.parse(self.idlFile)
  59         root = doc.childNodes[0]
  60
  61         for child in root.childNodes:
  62
  63             if child.nodeType == child.ELEMENT_NODE:
  64
  65                 # -----------------------------------------------------------------------
  66                 # 'child' is the main class node for a fieldmapper class.
  67                 # It has 'fields' and 'links' nodes as children.
  68                 # -----------------------------------------------------------------------
  69
  70                 id = self.__getAttr(child, 'id')
  71                 self.IDLObject[id] = {}
  72                 obj = self.IDLObject[id]
  73                 obj['fields'] = []
  74
  75                 obj['controller'] = self.__getAttr(child, 'controller')
  76                 obj['fieldmapper'] = self.__getAttr(child, 'oils_obj:fieldmapper', OILS_NS_OBJ)
  77                 obj['virtual'] = self.__getAttr(child, 'oils_persist:virtual', OILS_NS_PERSIST)
  78                 obj['rpt_label'] = self.__getAttr(child, 'reporter:label', OILS_NS_REPORTER)
  79                 obj['tablename'] = self.__getAttr(child, 'oils_persist:tablename', OILS_NS_REPORTER)
  80
  81                 keys = []
  82                 for classNode in child.childNodes:
  83                     if classNode.nodeType == classNode.ELEMENT_NODE:
  84                         if classNode.nodeName == 'fields':
  85                             keys = self.parseFields(id, classNode)
  86
  87                 osrf.net_obj.register_hint(id, keys, 'array')
  88
  89         doc.unlink()
  90
  91
  92     def parseFields(self, cls, fields):
  93         """Takes the fields node and parses the included field elements"""
  94
  95         keys = []
  96         idlobj = self.IDLObject[cls]
  97
  98         idlobj['field_meta'] = {
  99             'primary': self.__getAttr(fields, 'oils_persist:primary', OILS_NS_PERSIST),
 100             'sequence': self.__getAttr(fields, 'oils_persist:sequence', OILS_NS_PERSIST)
 101         }
 102
 103         for field in fields.childNodes:
 104             if field.nodeType == field.ELEMENT_NODE:
 105                 keys.append(None)
 106
 107         for field in fields.childNodes:
 108             obj = {}
 109             if field.nodeType == fields.ELEMENT_NODE:
 110                 name            = self.__getAttr(field, 'name')
 111                 position        = int(self.__getAttr(field, 'oils_obj:array_position', OILS_NS_OBJ))
 112                 obj['name'] = name
 113
 114                 try:
 115                     keys[position] = name
 116                 except Exception, e:
 117                     osrf.log.log_error("parseFields(): position out of range.  pos=%d : key-size=%d" % (position, len(keys)))
 118                     raise e
 119
 120                 virtual = self.__getAttr(field, 'oils_persist:virtual', OILS_NS_PERSIST)
 121                 obj['rpt_label'] = self.__getAttr(field, 'reporter:label', OILS_NS_REPORTER)
 122                 obj['rpt_dtype'] = self.__getAttr(field, 'reporter:datatype', OILS_NS_REPORTER)
 123                 obj['rpt_select'] = self.__getAttr(field, 'reporter:selector', OILS_NS_REPORTER)
 124                 obj['primitive'] = self.__getAttr(field, 'oils_persist:primitive', OILS_NS_PERSIST)
 125
 126                 if virtual == string.lower('true'):
 127                     obj['virtual']  = True
 128                 else:
 129                     obj['virtual']  = False
 130
 131                 idlobj['fields'].append(obj)
 132
 133         return keys
 134
 135
 136
 137