Demo/xml/elem_count.py

   1 """
   2 A simple demo that reads in an XML document and displays the number of
   3 elements and attributes as well as a tally of elements and attributes by name.
   4 """
   5
   6 import sys
   7 from collections import defaultdict
   8
   9 from xml.sax import make_parser, handler
  10
  11 class FancyCounter(handler.ContentHandler):
  12
  13     def __init__(self):
  14         self._elems = 0
  15         self._attrs = 0
  16         self._elem_types = defaultdict(int)
  17         self._attr_types = defaultdict(int)
  18
  19     def startElement(self, name, attrs):
  20         self._elems += 1
  21         self._attrs += len(attrs)
  22         self._elem_types[name] += 1
  23
  24         for name in attrs.keys():
  25             self._attr_types[name] += 1
  26
  27     def endDocument(self):
  28         print "There were", self._elems, "elements."
  29         print "There were", self._attrs, "attributes."
  30
  31         print "---ELEMENT TYPES"
  32         for pair in  self._elem_types.items():
  33             print "%20s %d" % pair
  34
  35         print "---ATTRIBUTE TYPES"
  36         for pair in  self._attr_types.items():
  37             print "%20s %d" % pair
  38
  39 if __name__ == '__main__':
  40     parser = make_parser()
  41     parser.setContentHandler(FancyCounter())
  42     parser.parse(sys.argv[1])