Simple interface to minidom for creating XML files

[Raphaël Plasson]

Hello,

I want to create some XML files, following a simple template. For that
purpose, I created a simple interface to minidom. This is simple code,
but as I spend a little time for understanding how minidom was
working, I thought that this may be useful for someone (not that
minidom is complex, but even if simplified from the full XML
implementation, it still possesses too many functions for what I
simply wanted to do).

What you have to do is just to import the class doc, and then:

In [258]: xml=doc("toto")
In [259]: xml["part1"]=None
In [260]: xml["part1"]["1.1"]="coucou"
In [261]: xml["part1"]["1.2"]="toto"
In [262]: xml["part1"]["1.2"]["1.2.1"]="a"
In [263]: xml["part1"]["1.2"]["1.2.2"]="b"
In [264]: xml["part2"]="That's all folks!"
In [265]: xml["part1"]["1.2"]["1.2.2"]="really b"
In [266]: xml["part1"]["cdata"]="This is\nMore complex data\n\n"
In [267]: xml.write("test.xml")

is sufficient to obtain the following file:

<?xml version="1.0" ?>
<toto>
<part1>
<1.1>
coucou
</1.1>
<1.2>
toto
<1.2.1>
a
</1.2.1>
<1.2.2>
really b
</1.2.2>
</1.2>
<![CDATA[This is
More complex data

]]>
</part1>
<part2>
That's all folks!
</part2>
</toto>

This piece of code is way too small for being considered as a real
package, but it may help someone. Thus, I am just posting it here so
that it doesn't get lost. Please feel free to use it and extend it as
will (I put a GPL licence in that purpose).
If you have some comments/suggestion about this code, I would also be
happy to discuss about it .

Raphaël


Here is the code:

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# Copyright 2010 Raphael Plasson, rplasson_at_gmail_dot_com
#
# This program is free software: you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/

.

from xml.dom.minidom import Document

class node:
def __init__(self,name,parent,doc):
'''Add a node called <name> to the document <doc> inside the
node <parent>'''
self.name=name
self.parent=parent
self.doc=doc
self.element=self.doc.createElement(self.name)
self.parent.element.appendChild(self.element)
self.children={}
def __getitem__(self,key):
return self.children[key]
def __setitem__(self,key,val):
if key=="text":
self.set_text(val)
elif key=="cdata":
self.set_cdata(val)
else:
tmp=self.set_node(key)
if val != None:
tmp.set_text(val)
def __repr__(self):
tmp=self.name+" : "
for i in self.children:
tmp += i+", "
return tmp
def __newchild(self,child,name):
self.children[name] = child
def set_node(self,name):
'''Add a node <name>.
If a node with the same name already exists,
it is simply returned.'''
if self.children.has_key(name):
return self.children[name]
else:
tmp=node(name,self,self.doc)
self.__newchild(tmp,name)
return tmp
def set_text(self,text):
'''Add or update the node text <text>'''
if self.children.has_key("text"):
self.children["text"].data=text
else:
tmp=self.doc.createTextNode(text)
self.__newchild(tmp,"text")
self.element.appendChild(tmp)
def set_cdata(self,cdata):
'''Add or update the node cdata <cdata>'''
if self.children.has_key("cdata"):
self.children["cdata"].data=cdata
else:
tmp=self.doc.createCDATASection(cdata)
self.__newchild(tmp,"cdata")
self.element.appendChild(tmp)
self.element.appendChild(self.doc.createTextNode("")) #
dirty hack for adding newline after CDATA in file
def set_attr(self,attr,val):
'''Add or set the attribute <attr> to <val>'''
self.element.setAttribute(attr,val)
def comment(self,comm):
'''Add the comment <comm>'''
self.element.appendChild(self.doc.createComment(comm))

class doc(node):
def __init__(self,name):
''' Create an xml document, with root node <name>'''
self.name=name
self.parent=None
self.doc=Document()
self.element=self.doc.createElement(self.name)
self.doc.appendChild(self.element)
self.children={}
self.text=""
def write(self,filename):
''' Write the xml document to <filename>'''
out=file(filename,"w")
self.doc.writexml(out, newl="\n", addindent=" ")
out.close()

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