Re: Should I coerce a DBIC schema from HashRef?

Bill,

I've done this a lot in the past, as well as a few other approaches.  In the end I've come to the conclusion that although off the top it seems like a nice interface, it doesn't grow old well and can be confusing to people trying to read your code.  I now tend to think that a consuming class should only build its objects when and if it needs some way to influence how they are built.  Otherwise over the long term you end up with a confusing interface with a lot of stuff completely unrelated to the actual functioning of the class.  And it harder to test correctly.

I'm not sure what a better approach could be, but lately I've been taking the idea of having dedicated builder classes.  I know that sounds heavy handed, but at least it has the upside that my concerns are more carefully separated.

Good luck and very interested where this thread goes!

John



>________________________________
> From: Bill Moseley <[email protected]>
>To: [email protected] 
>Sent: Tuesday, September 4, 2012 2:07 PM
>Subject: Should I coerce a DBIC schema from HashRef?
> 
>Looking for a bit of guidance on design.
>
>I have a growing number of classes that require a DBIx::Class "schema"
>attribute.  These classe are used as Models in Catalyst (where they get the
>Catalyst app's schema passed in to the constructor), but they are also used
>in command line tools and cron jobs.
>
>It makes sense to coerce a URI object from a string, and even a DateTime
>from an integer or a string -- and MooseX::Types::DateTime and
>MooseX::Types::URI do that. But MooseX::Types::DBIx::Class does not coerce
>a schema object.
>
>Is there any reason I would not want to coerce a schema from a hashref?
>
>I guess another option would be a role that includes individual attributes
>for schema class, dsn, user, passwords, and \%options and use a
>_build_schema method.   This is an approach I've used in the past.
>
>BTW, I used DBIC as a familiar example, but many of my classes need more
>than just a DBIC schema -- they often need a logger, and a few other
>classes so this question isn't limited to building a schema object.
>
>-- 
>Bill Moseley
>[email protected]
>
>
>