[Dbix-class] Time-based Relatiosnhips

[Dave Cross]

I think I'm missing something obvious here. But I've fried my brain  
thinking about it.

A foo can have many associated bars. So I have this.

__PACKAGE__->has_many(
     'bars' => 'MyDB::Result::Bar',
     { 'foreign.foo_id' => 'self.id' },
);

But, each bar has start and end dates associated with it. So at most  
one bar record is active for a foo at any given time[1].

I thought I could do something like this:

__PACKAGE__->might_have(
     'active_bar' => 'MyDB::Result::Bar',
     {
       'foreign.foo_id' => 'self.id',
       'foreign.start'  => { '<=' => \'now()' },
       'foreign.end     => { '>=' => \'now()' }
     },
);

But I get an error saying 'Invalid rel cond val'. This comes from code  
in DBIx::Class::ResultSource::_resolve_condition which checks that all  
values in the condition hash include the string 'self'.

So how do I model this relationship? Am I mad for even trying?

Dave...

[1] Yes, this is hard to maintain. But the schema isn't going to change.