[Zope] acquisition context within product method

[Jonathan Hobbs]

From: "Richard Rosenberg" <richrosenberg at earthlink.net>
> Allow me to start off by saying I have just finished going through the  
> Zope Bible, and this is purely an educational exercise. This particular  
> product class will (in the end I hope) essentially be a sort of query  
> template that relies on zSQL methods. It began as an experiment to  
> determine if I could get by with only 2 zSQL methods to serve all  
> queries (except DELETEs, which at the moment I am not interested in)  
> sent to a database connection. Before anyone gets upset, please keep in  
> mind that this is an experimental effort only at this point.
> 
> At the moment I have 2 (rather lengthy) zSQL methods - one for SELECTs  
> and one for UPDATEs/INSERTs - that properly handle most types of joins,  
> and support just about any WHERE clause. Each zSQL method expects one  
> argument, which is a list of dictionaries (for SELECTs a list  
> containing one dictionary). The dictionaries which comprise the query  
> parameter are constructed via 3 python scripts and 3 DTML documents.  
> Each of the DTML documents gathers information from the user and each  
> script is called when the rendered DTML from is submitted:
> 
> DTML 1 asks for a database connection ID from a dropdown list, and on  
> submit calls a script that retrieves a listing of all of the available  
> tables via one of the aforementioned zSQL methods. The same script then  
> returns DTML 2. . .
> 
> DTML 2 displays a listing of tables from which the user must select one  
> or more table names. DTML 2 then calls another script that retrieves a  
> listing of all available field names for each table, along with type  
> information for each field. The same script then returns DTML 3. . .
> 
> DTML 3 allows the user to define join criteria if applicable, fields to  
> include in the result, and any selection criteria (sql WHERE clause).  
> On submit DTML 3 then calls yet another script which uses all of the  
> gathered information thus far to construct and validate the parameter  
> sent to the existing zSQL method. A final DTML page is returned to  
> display the results for testing purposes.
> 
> So I thought. . .would it even be possible to make this into a product?  
> I realize that it may not be desirable, but is it possible?
> 
> Presently, when I select the product from the product add list, the  
> first step (selecting a connection id on a DTML document) goes fine,  
> and it calls a module level level function to retrieve the listing of  
> tables. The function chokes when it attempts to return another DTML  
> document on the following line:
> 
> return Step2Form(self, request) 
> 
> which is why I ask the question:
> 
> How does one create a product which relies on multiple pages to gather  
> information from the user when the product instance is added to a  
> folder via the product add list (a wizard-like interface)? Can it be  
> done, or is this a limitation of Zope?
> 
> In messing around with this I have found precious little information  
> related to this specific question, and I am aware of no products which  
> implement this functionality in their 'product add' process. In fact,  
> it seems to be conspicuously absent. Thanks.

There may be some hints in a couple of Dieter's packages:

http://www.dieter.handshake.de/pyprojects/zope/Wizzard.html

http://www.dieter.handshake.de/pyprojects/zope/Dispatcher.html


Jonathan