Question

I have some IronPython code which makes use of XmlTextWriter which allows me to write code like

self.writer = System.Xml.XmlTextWriter(filename, None)
self.writer.Formatting = Formatting.Indented
self.writer.WriteStartElement(name)
self.writer.WriteString(str(text))
self.writer.WriteEndElement()

...

self.writer.Close()

I would like to make my code portable across Python implementations (CPython, IronPython and Jython). Is there a streaming Python XML writer I can use for this without needing to use either print statements, or to construct a whole DOM tree before writing it out to file?

Answer 1

I wrote a module named loxun to do just that: http://pypi.python.org/pypi/loxun/. It runs with CPython 2.5 and Jython 2.5, but I never tried it with IronPython.

Example usage:

with open("...", "wb") as out:
  xml = XmlWriter(out)
  xml.addNamespace("xhtml", "http://www.w3.org/1999/xhtml")
  xml.startTag("xhtml:html")
  xml.startTag("xhtml:body")
  xml.text("Hello world!")
  xml.tag("xhtml:img", {"src": "smile.png", "alt": ":-)"})
  xml.endTag()
  xml.endTag()
  xml.close()

And the result:

<?xml version="1.0" encoding="utf-8"?>
<xhtml:html xlmns:xhtml="http://www.w3.org/1999/xhtml">
  <xhtml:body>
    Hello world!
    <xhtml:img alt=":-)" src="smile.png" />
  </xhtml:body>
</xhtml:html>

Among other features, it detects missalligned tags while you write, uses a streaming API with a small memory footprint, supports Unicode and allows to disable pretty printing.