[XML-SIG] how to output xml from a python object

[paul@boddie.net]

>"Dave Primmer" <primmer@hotmail.com> writes:
>
>> I'd like to do something like take a simple python object and make an
>> xml file. I've looked and looked but I can't find any docs on how to
>> do this (only parsing). 

martin@v.loewis.de (Martin v. Loewis) wrote:
>
>I recommend
>
>print '<object name="%s" city="%s"><desc>%s</desc></object>' % \
>   (object.name, object.city, object.desc)
>
>Care is needed if the attributes may contain markup.

I recommend avoiding these printing exercises, for mainly the same reasons that 
people should avoid quoting values in SQL statements - it's easy to forget to 
quote things, and while security holes are less likely to be opened in this 
case, getting some valid input and then seeing things go badly wrong is not 
very appealing.

By the time quoting functions and other extra safeguards are included in your 
code, you would have been better off in terms of code readability, 
standardisation and extensibility if you had just used the DOM instead. After 
all, the various serialisation functions and classes in PyXML have been 
designed to do this kind of thing, and I don't believe in reinventing the wheel 
poorly.

On a related note, I uploaded my introductory document again, and this is 
precisely the kind of thing I covered in that document:

  http://www.boddie.org.uk/python/XML_intro.html

Having had to maintain code which did lots of print statements (in Perl as 
well, for increased maintenance excitement), I can see lots of benefits in not 
using that approach. Another benefit of the DOM, of course, is the random-
access nature of the technology - as soon as you decide you need to revisit 
parts of your generated document in your program in order to add "extra stuff" 
(and I'm not saying you definitely will, but it's not unheard of), you'll 
probably end up doing a big rewrite of the program to use the DOM anyway.

Paul