[Zope] DTML rendering from python?

[Michiel Toneman]

Hi Dylan, hi Andy

Great answers, very true and also useful, thanks. "Don't do it that
way!" has in the past been some of the best advice given to me.

(Un?)Fortunately, I just put the "<p><dtml-var id></p>" in there as an
example to simplify the explanation of my problem, and (I think) I have
a valid reason for wanting to do this. (I'd love some feedback on this.
If you decide I'm nuts anyway, I'll probably have agree with you ;-) )
 
> Second, use DTML how it's designed, namely for inserting dynamic 
> information into a pre-defined layout.

I wouldn't dream of putting HTML in that spot in the "real" application,
but I'm a bit of a HTML purist, and I can't bear to see content loose on
a page without a proper HTML "p" wrapper ;-) 

What I'm actually doing is building a Content Management system for
which the layouts are not pre-defined. The content manager edits content
using structured text. The getHTML function takes the structured text,
translates this into a HTML snippet. This part is easily achieved in
DTML only. Now it gets tricky, though. I need to insert small "info
boxes" into the html. These are "floated" just after a paragraph tag.
Not all paragraphs have such a floating info-box, this is selectable by
the content manager.

The HTML might look like this:

----------------------------------------------------------
<h2>Lorem ipsum dolor sit elitr</h2>
  <p> 
    <div style="float:right; width: 150px;"> 
      <img src="images/voorbeeld4.jpg" alt="voorbeeld" /><br />
      Lorem ipsum dolor
    </div>
    Sed diam nonumy eirmod tempor invidunt ut labore et 
    dolore magna aliquyam erat, sed diam voluptua. 
  </p>
----------------------------------------------------------

where the "div" is opional. This is the part that DTML can't handle.
To do this, I feed the HTML Snippet to the DOM parser, locate all the
paragraphs, and insert a "dtml-var" tag just after the "p" tag where
ever a "floating box" should be present. 

I have thus preprocessed the structured-text into resultant DTML, for
which I'd like to let the DTML renderer do the heavy lifting. I was
hoping that simply rendering getHTML in a DTML document would do the
trick, but the return value is output "raw" into the DTML document.

My "real" code therefore looks like:

---------------------------------------------------------------

from StructuredText import DocumentClass
from StructuredText import HTMLClass
from xml.dom.minidom import parse, parseString


..snip...

    def getHTML(self):
        "Returns HTML for page"
        #return self._htmltxt
        Doc  = DocumentClass.DocumentClass()
        HTML = HTMLClass.HTMLClass()
        text = Doc(ST.StructuredText(self._htmltxt))
        html = "<div>" + HTML(text, level=2, header=0) + "</div>"
        dom  = parseString(html)
        pars = dom.getElementsByTagName("p")

        parcount = 0
        for i in pars:
            parcount += 1
            c = dom.createComment("#var par%d" %parcount)
            ref = i.firstChild
            i.insertBefore(c, ref)

        html = dom.toxml()

-----------------------------------------------------------

I'd be grateful for any feedback. Either an alternative approach, or a
way to render getHTML as DTML in a DTMLDocument. 

Sorry for the long posting.

Greetings,

Michiel