[XML-SIG] Simple DOM question (writing DOM)

[Thomas B. Passin]

[Martin v. Loewis]

>...
>
> > This sounds a little bit too unstructured to me. Btw. I've meanwhile
> > got the transformation from/to XML working. I'm quite happy with it
> > and it's not too much work in comparison with print/write. Any
> > comments?
>
> Two of them:
>
> 1. Sometimes, people have specific ideas of how the XML should look
>    like on a lexical level (what encoding to use, where to insert
>    whitespace, etc). Producing a DOM tree and invoking .xml() does not
>    give you that flexibility. It may not be needed in your
>    application, so this might not be an issue.
>
> 2. Keep Unicode strings as long as you can. I see that you use
>    .encode("utf-8") in fromxml, and put back the UTF-8 strings in
>    toxml. Strictly speaking, this is breaking the DOM contract: All
>    strings in DOM are Unicode; byte strings are only accepted for
>    backwards compatibility. You should really carry over the Unicode
>    objects, and keep them until you need to print them into a byte
>    stream.
>

Remember, if you produce output strings, don't use

str=str+data

to build up really long strings - because it gets very slow (see a thread on
this a month or so ago).  Either output short strings as you go, or put the
string pieces into a list then join the list, or use StringIO - that will be
MUCH faster.

Cheers,

Tom P