Geek asks and answers

How to insert DTD DOCTYPE contents when using SAX to generate XML output in Python

I am trying to create a large XML file using python (actually jython) xml.sax.saxutils.XMLGenerator. I would like to include the DTD information, but I could not figure out how to pass the SAX DTD string. Here is an example SAX writer class:

from xml.sax.saxutils import XMLGenerator

class xml_writer:
    def __init__(self, output, encoding):
        """
        an XML writer object that generate xml output to a file
        """
        xmlwriter = XMLGenerator(output, encoding)
        xmlwriter.startDocument()
        self._writer = xmlwriter
        self._output = output
        self._encoding = encoding

        self.attr_vals = {}
        self.attr_qnames = {}
        return

    def start_elem(self, name):
        name = unicode(name)
        attrs = AttributesNSImpl(self.attr_vals, self.attr_qnames)
        self._writer.startElementNS((None, name), name, attrs)
        self._writer._out.write('\n')
        self.attr_qnames = {}
        self.attr_vals = {}

    def end_elem(self, name):
        name = unicode(name)
        self._writer.endElementNS((None, name), name)
        self._writer._out.write('\n')

    def setAttribute(self, aname, value):
        aname = unicode(aname)
        value = unicode(value)
        self.attr_vals[(None, aname)] = value
        self.attr_qnames[(None, aname)] = aname

    def close(self):
        """
        Clean up 
        """
        self._writer.endDocument()
        return

Appreciate your help.

+3
source share
1 answer

You can subclass XMLGeneratorand add a method write(). Here is an example:

import sys
from xml.sax.saxutils import XMLGenerator

class MyXMLGenerator(XMLGenerator):
    def __init__(self, out=sys.stdout, encoding="UTF-8"):
        XMLGenerator.__init__(self, out, encoding)
        self.out = out

    def write (self,s):
        self.out.write(s)

def writexml(out):
    xmlwriter = MyXMLGenerator(out)
    xmlwriter.startDocument()
    xmlwriter.write("<!DOCTYPE test SYSTEM 'test.dtd'>\n")
    xmlwriter.startElement('test', {"a": "1"})
    xmlwriter.characters('abc123')
    xmlwriter.endElement('test')
    xmlwriter.endDocument()

if __name__ == '__main__':
    writexml(out=open("out.xml", "w"))

Result in out.xml :

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE test SYSTEM 'test.dtd'>
<test a="1">abc123</test>
+3
source

More articles:


All Articles