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Python Manipulating XML

A short script with descriptions for reading and manipulating xml.  It seems like the python ElementTree module should be the easiest and best suited for XML manipulation.  However I had a complicated XML structure with multiple namespaces and lxml handled it better.  ElementTree could only handle one namespace with it;s register function. In addition lxml has pretty_print which might be useful.  Although in my case when I do inserts pretty_print did not work even with the FAX fix for remove_blank_text.

import lxml.etree as ET

f = open('config.xml','rb')
## http://lxml.de/FAQ.html#why-doesn-t-the-pretty-print-option-reformat-my-xml-output
#parser = ET.XMLParser(remove_blank_text=True)
#tree = ET.parse(f, parser)
tree = ET.parse(f)

#for element in tree.iter():
#    element.tail = None

root = tree.getroot()
namespace="http://xmlns.oracle.com/weblogic/domain"
servers = tree.findall('.//{%s}server' % namespace)

## Loop through the nodes we found
for server in servers:
  print "New SERVER node detected:"
  for child in server:
    tag = child.tag
    val = child.text
    ## Remove any existing children
    if tag == "{http://xmlns.oracle.com/weblogic/domain}ssl":
      print "found server.ssl and will remove",
      server.remove(child)
    if tag == "{http://xmlns.oracle.com/weblogic/domain}log":
      print "found server.log and will remove",
      server.remove(child)
    if tag == "{http://xmlns.oracle.com/weblogic/domain}data-source":
      print "found server.data-source and will remove",
      server.remove(child)
    print tag, val
  
  ## Add the 3 children we want 
  child = ET.Element("ssl")
  child.text=''
  server.insert(1,child)
  ##  Check out why xsi:nil is not working. UTF???
  ##  gchild = ET.Element("hostname-verifier",attrib={'xsi:nil':'true'})
  gchild = ET.Element("hostname-verifier",attrib={'xsi_nil':'true'})
  gchild.text=''
  child.insert(1,gchild)
  gchild = ET.Element("hostname-verification-ignored")
  gchild.text='true'
  child.insert(2,gchild)
  gchild = ET.Element("client-certificate-enforced")
  gchild.text='true'
  child.insert(3,gchild)
  gchild = ET.Element("two-way-ssl-enabled")
  gchild.text='false'
  child.insert(3,gchild)
  
  child = ET.Element("log")
  child.text=''
  server.insert(2,child)
  gchild = ET.Element("rotation-type")
  gchild.text='byTime'
  child.insert(1,gchild)
  gchild = ET.Element("number-of-files-limited")
  gchild.text='true'
  child.insert(2,gchild)
  gchild = ET.Element("rotate-log-on-startup")
  gchild.text='true'
  child.insert(3,gchild)
  
  child = ET.Element("data-source")
  child.text=''
  server.insert(3,child)
  gchild = ET.Element("data-source-log-file")
  gchild.text=''
  child.insert(1,gchild)
  ggchild = ET.Element("rotation-type")
  ggchild.text='byTime'
  gchild.insert(1,ggchild)
  ggchild = ET.Element("number-of-files-limited")
  ggchild.text='true'
  gchild.insert(2,ggchild)
  ggchild = ET.Element("rotate-log-on-startup")
  ggchild.text='true'
  gchild.insert(3,ggchild)

## Check out why pretty_print is not making newlines in new tags  
#print(ET.tostring(tree, pretty_print=True))
tree.write("wc-out.xml", pretty_print=True)
Published inPythonXML