ZopeLABS - Pass multiple values from python script to DTML

Pass multiple values from python script to DTML. Taken from a mailing list post by Duncan Booth

If you want to return a single value, just return it and use dtml-var to
insert it into your document at one location, or dtml-let to save the
value for use in several places.
DTML:
<dtml-var myscript>
PythonScript myscript:
return "return value"

If you want to return multiple values, then return a namespace
object and use dtml-with to make the values available for use. The
example below shows the technique I prefer, which is to make all
python scripts return a namespace.

For example, the following code is taken from a simple shopping basket system. basketSummary displays a one line summary of the basket contents: <dtml-comment> This method returns an HTML segment that displays a summary of the contents of the current shopping basket. </dtml-comment> <dtml-with "logic.basketContents()"> <p class="small">Shopping Basket: <dtml-var numlines> lines, <dtml-var numitems> items, Total Value: <dtml-var totalvalue fmt="$%1.2f"> </p> </dtml-with> The python script basketContents, kept in the logic folder, retrieves the current contents of the basket and looks like this: if not context.REQUEST.has_key('SESSION'): context.Session(REQUEST=context.REQUEST) basket = context.REQUEST.SESSION.get('basket', None) or [] customer = container.customerData() # Return the basket contents. contents = [] totalvalue, items = 0.0, 0 for c, d, u, q, p in basket: contents.append(namespace(code=c, description=d, unitprice=u, quantity=q, price=p)[0]) totalvalue, items = totalvalue + p, items + q shipping = 4.95 total = totalvalue + shipping vars = namespace(contents=contents, totalvalue=totalvalue, shipping=shipping, total=total, numlines=len(contents), numitems=items, customer=customer[0]) return vars Notice that for the summary display we are just interested in the totals. The code that does the full display can get at the individual lines using dtml-in: <dtml-with "logic.basketContents()"> <dtml-in contents> <dtml-var description> <dtml-var unitprice> etc. </dtml-in contents> </dtml-with> Note that the namespace function actually returns a tuple containing the namespace as the first (only) element. This is fine when returning the final result, but for building a list of namespaces you have to remove the extra tuple wrapping, hence the [0] in the append call (and also the customer[0] since customer was the result of another call to namespace). -- Duncan Booth duncan@rcp.co.uk