Inserting xml nodes in an existing xml document with python

Question

I am trying to insert xml nodes in this document:

</providers>

</root>

I wrote this code: import xml.dom.minidom as m

doc = m.parse("monfichier.xml")
valeurs = doc.getElementsByTagName("providers")
element = doc.createElement("provider")
valeurs.appendChild(element)

elthost = doc.createElement("hostnamep") 
eltLTVC = doc.createElement("LocalTrustValueC")
element.appendchild(elthost)
element.appendchild(eltLTVC)

texteHost = doc.createTextNode("machinename")
texteLTVC = doc.createTextNode("23") 
eltHost.appendChild(texteHost)
eltLTVC.appendChild(texteLTVC)
doc.writexml(open("monfichier.xml","w"))

And I want to obtain at the end this xml document : machinename 23

    </provider> 
</providers>

</root>

But I obtained this error : valeurs.appendChild(element) AttributeError: 'NodeList' object has no attribute 'appendChild'

Answer 1

As per the OP's interest in an XSLT solution:

Here is a complete and short XSLT solution:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:strip-space elements="*"/>

 <xsl:template match="node()|@*">
  <xsl:copy>
   <xsl:apply-templates select="node()|@*"/>
  </xsl:copy>
 </xsl:template>

 <xsl:template match="providers">
  <providers>
        <provider>
            <hostnamep>machinename</hostnamep>
            <LocalTrustValueC>23</LocalTrustValueC>
        </provider>
  </providers>
 </xsl:template>
</xsl:stylesheet>

when this transformation is applied on the provided XML document:

<root>
    <providers> 
    </providers>
</root>

the wanted, correct result is produced:

<root>
   <providers>
      <provider>
         <hostnamep>machinename</hostnamep>
         <LocalTrustValueC>23</LocalTrustValueC>
      </provider>
   </providers>
</root>

Answer 2

Based on some quick reading of http://docs.python.org/library/xml.dom.html#dom-node-objects it appears that NodeList does not have an appendChild method. Instead you want to get the first Node in the result set(since your post implies there is only one) and call appendChild on that node.

valeurs = doc.getElementsByTagName("providers").item(0)
element = doc.createElement("provider")
valeurs.appendChild(element)