[fw-auth] Zend_Acl and pagination

Hello!

Got an interesting problem I was hoping some of you could help me with.  I'm trying to figure out the best way to do result set pagination in combination with Zend_Acl-based access control.  Let me explain…

Start with the following assumptions:

1. You have a database table containing 500 or so blog posts.
2. One of the resources set up in your Bootstrap class is a Zend_Acl object, containing all the rules you'll need to control access to those blog posts.  Some of these rules might be based on stuff in the database, but some of them might not be…the ACL object controls all that.
3. You want to set up a paginated listing view for your blog posts; each page is to list exactly 10 posts, and contain pagination links to get to all the other pages.

So, in the action method for that listing view, we do the following:

1. Pull the models in by database query (really, the query would probably be in a service layer rather than hard-coded into the action, but for this example that's not really important)
2. Loop through the result set and check each result against the ACL object to see if it's allowed for the current user; if not, remove it from the result set.
3. Pass the adjusted result set to the view for rendering.

Suppose, however, that of the 10 results we get back, 3 of them aren't permissible for the current user.  That means we're only left with 7 results to show, when the user is expecting 10.  Or, suppose that of the 10 results, all 10 are impermissible…in that case, the user sees nothing but a set of pagination links, with no guarantee that any of the links will lead to better results.

Now, one possible solution here would be to adjust the database query to account for access control, but then we'd have to maintain access control logic in two places: the ACL and the database query itself.  Plus, if the ACL object is basing its rules on information not found in the database (dunno how realistic that is, but I'm exploring all angles), we can't take this approach at all.

So the problem in a nutshell is this: how can I ensure a paginated result set of exactly 10 items per page when the access control is handled outside of the database query?

Thanks!
Adam Jensen