wxPython/samples/ide/activegrid/util/utillang.py

   1 #----------------------------------------------------------------------------
   2 # Name:         utillang.py
   3 # Purpose:      Provide language specific utilities
   4 #
   5 # Author:       Joel Hare
   6 #
   7 # Created:      8/23/05
   8 # CVS-ID:       $Id$
   9 # Copyright:    (c) 2004-2005 ActiveGrid, Inc.
  10 # License:      wxWindows License
  11 #----------------------------------------------------------------------------
  12
  13 import os
  14 import sys
  15 import UserDict
  16 import tempfile
  17 import xml.sax.saxutils as saxutils
  18
  19 import activegrid.util.parser as parser
  20
  21 PY2WEB_codepages = {
  22      'cp1251' : 'CP-1251',
  23      'koi8_r' : 'KOI8-R',
  24 }
  25
  26 def evalXPath(xpath, data, specialEntries=None):
  27     codeStr = parser.xpathToCode(xpath)
  28     return evalCode(codeStr, data, specialEntries)
  29
  30 def evalCode(codeStr, data, specialEntries=None):
  31     if isinstance(data, ObjAsDict):
  32         namespace = data
  33     elif isinstance(data, dict):
  34         namespace = dict(data)
  35     else:
  36         namespace = ObjAsDict(data)
  37     if specialEntries:
  38         for key, value in specialEntries.items():
  39             namespace.addSpecialEntry(key, value)
  40     return eval(codeStr, {}, namespace)
  41
  42 def deriveCharset():
  43     charset = None
  44     encodingString = sys.getdefaultencoding()
  45     if encodingString != 'ascii':
  46         charset = PY2WEB_codepages.get(encodingString.lower())
  47         if charset == None:
  48             charset = encodingString
  49     return charset
  50
  51 def toUTF8(value):
  52     """
  53     Converts all unicode and non-string values to utf-8.
  54     This assumes string instances are already encoded in utf-8.
  55     Note that us-ascii is a subset of utf-8.
  56     """
  57     if isinstance(value, unicode):
  58         return value.encode('utf-8')
  59     return str(value)
  60
  61 def toUnicode(value):
  62     """
  63     Converts all strings non-string values to unicode.
  64     This assumes string instances are encoded in utf-8.
  65     Note that us-ascii is a subset of utf-8.
  66     """
  67     if not isinstance(value, unicode):
  68         if not isinstance(value, str):
  69             return unicode(value)
  70         return unicode(value, 'utf-8')
  71     return value
  72
  73
  74 def getSystemTempDir():
  75     return tempfile.gettempdir()
  76
  77 def getEnvVar(name, defaultVal=None):
  78     if os.environ.has_key(name):
  79         return os.environ[name]
  80     return defaultVal
  81
  82 class ObjAsDict(UserDict.DictMixin):
  83     """
  84     Passing this to eval as the local variables dictionary allows the
  85     evaluated code to access properties in the wrapped object
  86     """
  87     def __init__(self, obj):
  88         self.obj = obj
  89         self.specialEntries = {}
  90
  91     def __getitem__(self, key):
  92         try:
  93             return getattr(self.obj, key)
  94         except AttributeError, e:
  95             if self.specialEntries.has_key(key):
  96                 return self.specialEntries[key]
  97             raise KeyError(e.args)
  98     def __setitem__(self, key, item): setattr(self.obj, key, item)
  99     def __delitem__(self, key): delattr(self.obj, key)
 100     def keys(self):
 101         ret=[]
 102         for i in list(dir(self.obj)+self.specialEntries.keys()):
 103             if i=="__doc__" or i=="__module__":
 104                 pass
 105             elif i not in ret:
 106                 ret.append(i)
 107         return ret
 108
 109     def addSpecialEntry(self, key, value):
 110         self.specialEntries[key] = value
 111
 112 global saxXMLescapeDoubleQuote
 113 saxXMLescapeDoubleQuote = {'"':'&quot;'}
 114
 115 global saxXMLescapesAllQuotes
 116 # IE doesn't support &apos; but it doesn't seem like we should need this escaped at all so I took it out.
 117 saxXMLescapesAllQuotes = {'"':'&quot;', "'":"&#039;"}
 118
 119 global saxXMLunescapes
 120 saxXMLunescapes = {'&quot;':'"', "&#039;":"'"}
 121
 122 def escape(data, extraEscapes=None):
 123     """Escape ', ", &, <, and > in a string of data.
 124
 125     Basically, everything that saxutils.escape does (and this calls that, at
 126     least for now), but with " and ' added as well.
 127
 128     TODO: make this faster; saxutils.escape() is really slow
 129     """
 130
 131     global saxXMLescapeDoubleQuote
 132     if (extraEscapes == None):
 133         extraEscapes = saxXMLescapeDoubleQuote
 134     return saxutils.escape(data, extraEscapes)
 135
 136 def unescape(data):
 137     """Unescape ', ", &, <, and > in a string of data.
 138
 139     Basically, everything that saxutils.unescape does (and this calls that, at
 140     least for now), but with " and ' added as well.
 141
 142     TODO: make this faster; saxutils.unescape() is really slow
 143     """
 144
 145     global saxXMLunescapes
 146     return saxutils.unescape(data, saxXMLunescapes)