[Zope] copy/paste problem with dtml

[Brian Lloyd]

> It appears to be a common problem and noone has yet come up 
> with an answer.
> Maybe someone from DC could explain what is wrong with the 
> cut/paste code or
> point out what we are all doing wrong. 
> 
> Once I find an answer I will write a HowTo so that others 
> don't bash thier
> heads against this like I have for the last week.

Hi guys,

I think that what you are running into is the fact that 
cut/copy and paste originated as a through-the-web only 
operation. It stored object references in the "clipboard",
which is really just a cookie containing the serialized 
object references. Of course, this won't work if you 
try to use cut/paste programmatically all within the 
same request - the manage_pasteObjects method will look 
for the "clipboard" cookie and fail to find it (and then
blow up). This is, in fact, what the "no clipboard data 
found" message you are seeing means.

Luckily, there is a way to do it programmatically - you 
just need to modify your code a little bit because you
have to manage the "clipboard data" yourself.

First, lets look at the behavior of manage_copyObjects. Its 
signature is: 

  manage_copyObjects(self, ids, REQUEST=None, RESPONSE=None)

If you call manage_copyObjects and pass a REQUEST object, it
will assume that it is being called through the web and store
the clipboard data in the RESPONSE object of the passed in 
REQUEST. If you do *not* pass a REQUEST, the method will 
*return* the clipboard data to the caller. So the first change
we need to make is to save the result of calling manage_copyObjects.

Next, look at manage_pasteObjects:

  manage_pasteObjects(self, cb_copy_data=None, REQUEST=None)

This method need *either* to get the "clipboard data" passed 
in explicitly (as cb_copy_data), or to get it from a cookie
in the passed in REQUEST. Since we are doing this all in one 
request, we'll need to pass the clipboard data in directly. 
Note that there is currently a dependency on the REQUEST 
being available in the current implementation (so that it 
can determine whether you are allow to perform the paste), 
so you'll need to pass in both the clip data and the REQUEST.

So here's an (untested) modification that should do what you
want - the only real difference is that we have to handle the 
clip data explicitly.

    <dtml-with Members>
      <dtml-with "_.getitem(uname).content">
        <dtml-call "REQUEST.set('my_clip_data',
manage_copyObjects(ids))">
      </dtml-with>
      <dtml-with "_.getitem(AUTHENTICATED_USER.getUserName()).content">
        <dtml-call "manage_pasteObjects(my_clip_data, REQUEST)">
      </dtml-with>   
    </dtml-with>
    

Hope this helps!


Brian Lloyd        brian@digicool.com
Software Engineer  540.371.6909              
Digital Creations  http://www.digicool.com