Tools/Python/XmlRoutines.py

   1 #!/usr/bin/env python
   2
   3 # Copyright (c) 2007, Intel Corporation
   4 # All rights reserved. This program and the accompanying materials
   5 # are licensed and made available under the terms and conditions of the BSD License
   6 # which accompanies this distribution.  The full text of the license may be found at
   7 # http://opensource.org/licenses/bsd-license.php
   8 #
   9 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 """This is an XML API that uses a syntax similar to XPath, but it is written in
  13 standard python so that no extra python packages are required to use it."""
  14
  15 import xml.dom.minidom
  16
  17 def XmlList(Dom, String):
  18   """Get a list of XML Elements using XPath style syntax."""
  19   if String == None or String == "" or Dom == None or Dom == "":
  20     return []
  21   if Dom.nodeType==Dom.DOCUMENT_NODE:
  22     Dom = Dom.documentElement
  23   if String[0] == "/":
  24     String = String[1:]
  25   tagList = String.split('/')
  26   nodes = [Dom]
  27   index = 0
  28   end = len(tagList) - 1
  29   while index <= end:
  30     childNodes = []
  31     for node in nodes:
  32       if node.nodeType == node.ELEMENT_NODE and node.tagName == tagList[index]:
  33         if index < end:
  34           childNodes.extend(node.childNodes)
  35         else:
  36           childNodes.append(node)
  37     nodes = childNodes
  38     childNodes = []
  39     index += 1
  40
  41   return nodes
  42
  43 def XmlNode (Dom, String):
  44   """Return a single node that matches the String which is XPath style syntax."""
  45   if String == None or String == ""  or Dom == None or Dom == "":
  46     return ""
  47   if Dom.nodeType==Dom.DOCUMENT_NODE:
  48     Dom = Dom.documentElement
  49   if String[0] == "/":
  50     String = String[1:]
  51   tagList = String.split('/')
  52   index = 0
  53   end = len(tagList) - 1
  54   childNodes = [Dom]
  55   while index <= end:
  56     for node in childNodes:
  57       if node.nodeType == node.ELEMENT_NODE and node.tagName == tagList[index]:
  58         if index < end:
  59           childNodes = node.childNodes
  60         else:
  61           return node
  62         break
  63     index += 1
  64   return ""
  65
  66 def XmlElement (Dom, String):
  67   """Return a single element that matches the String which is XPath style syntax."""
  68   try:
  69     return XmlNode (Dom, String).firstChild.data.strip()
  70   except:
  71     return ''
  72
  73 def XmlElementData (Dom):
  74   """Get the text for this element."""
  75   if Dom == None or Dom == '' or Dom.firstChild == None:
  76     return ''
  77   return Dom.firstChild.data.strip()
  78
  79 def XmlAttribute (Dom, AttName):
  80   """Return a single attribute named AttName."""
  81   if Dom == None or Dom == '':
  82     return ''
  83   try:
  84     return Dom.getAttribute(AttName)
  85   except:
  86     return ''
  87
  88 def XmlTopTag(Dom):
  89   """Return the name of the Root or top tag in the XML tree."""
  90   return Dom.firstChild.nodeName
  91
  92 def XmlParseFile (FileName):
  93   """Parse an XML file into a DOM and return the DOM."""
  94   try:
  95     f = open(FileName, 'r')
  96     Dom = xml.dom.minidom.parse(f)
  97     f.close()
  98     return Dom
  99   except:
 100     return xml.dom.minidom.parseString('<empty/>')
 101
 102 def XmlParseString (Str):
 103   """Parse an XML string into a DOM and return the DOM."""
 104   try:
 105     return xml.dom.minidom.parseString(Str)
 106   except:
 107     return xml.dom.minidom.parseString('<empty/>')
 108
 109 def XmlParseFileSection (FileName, Tag):
 110   """Parse a section of an XML file into a DOM(Document Object Model) and return the DOM."""
 111   try:
 112     f = open(FileName, 'r')
 113   except:
 114     return xml.dom.minidom.parseString('<empty/>')
 115   Start = '<' + Tag
 116   End = '</' + Tag + '>'
 117   File = ''
 118   while File.find(Start) < 0 or File.find(End) < 0:
 119     Section = f.read(0x1000)
 120     if Section == '':
 121       break
 122     File += Section
 123   f.close()
 124   if File.find(Start) < 0 or File.find(End) < 0:
 125     return xml.dom.minidom.parseString('<empty/>')
 126   File = File[File.find(Start):File.find(End)+len(End)]
 127   try:
 128     return xml.dom.minidom.parseString(File)
 129   except:
 130     return xml.dom.minidom.parseString('<empty/>')
 131
 132 def XmlParseStringSection (XmlString, Tag):
 133   """Parse a section of an XML string into a DOM(Document Object Model) and return the DOM."""
 134   Start = '<' + Tag
 135   End = '</' + Tag + '>'
 136   File = XmlString
 137   if File.find(Start) < 0 or File.find(End) < 0:
 138     return xml.dom.minidom.parseString('<empty/>')
 139   File = File[File.find(Start):File.find(End)+len(End)]
 140   try:
 141     return xml.dom.minidom.parseString(File)
 142   except:
 143     return xml.dom.minidom.parseString('<empty/>')
 144
 145 def XmlSaveFile (Dom, FileName, Encoding='UTF-8'):
 146   """Save a DOM(Document Object Model) into an XML file."""
 147   try:
 148     f = open(FileName, 'w')
 149     f.write(Dom.toxml(Encoding).replace('&quot;','"').replace('&gt;','>'))
 150     f.close()
 151     return True
 152   except:
 153     return False
 154
 155 def XmlRemoveElement(Node):
 156   """Remove an element node from DOM(Document Object Model) tree."""
 157   ParentNode = Node.parentNode
 158   if ParentNode == None:
 159     return False
 160   PreviousSibling = Node.previousSibling
 161   while PreviousSibling != None and PreviousSibling.nodeType == PreviousSibling.TEXT_NODE and PreviousSibling.data.strip() == '':
 162     Temp = PreviousSibling
 163     PreviousSibling = PreviousSibling.previousSibling
 164     ParentNode.removeChild(Temp)
 165   ParentNode.removeChild(Node)
 166   return True
 167
 168 def XmlAppendChildElement(ParentNode, TagName, ElementText='', AttributeDictionary = {}):
 169   """Add a child element to a DOM(Document Object Model) tree with optional Attributes."""
 170   TagName = TagName.strip()
 171   if TagName == '':
 172     return None
 173   Depth = 0
 174   Dom = ParentNode
 175   while Dom != None and Dom.nodeType != Dom.DOCUMENT_NODE:
 176     Dom = Dom.parentNode
 177     Depth += 1
 178   if Dom == None:
 179     return None
 180   ParentNode.appendChild(Dom.createTextNode('\n%*s' % (Depth * 2, '')))
 181   ElementNode = Dom.createElement(TagName)
 182   if ElementText != '':
 183     ElementNode.appendChild(Dom.createTextNode(ElementText))
 184   for Item in AttributeDictionary:
 185     ElementNode.setAttribute(Item, AttributeDictionary[Item])
 186   ParentNode.appendChild(ElementNode)
 187   return ElementNode
 188
 189
 190 # This acts like the main() function for the script, unless it is 'import'ed into another
 191 # script.
 192 if __name__ == '__main__':
 193
 194   # Nothing to do here. Could do some unit tests.
 195   pass