Bill
Yes, I have pondered the same question.
My current solution is to have a MooseX::Singleton class that defines
all constants used in my database (and perhaps elsewhere in my
application). e.g.
package MyApp::Constants;
use MooseX::Singleton;
has track_type_foo => (is => 'ro', default = 1);
has track_type_bar => (is => 'ro', default = 2);
----
Then, as per Moosex::Singeton I initialize it once at the start of my
application.
MyApp::Constant->initialize;
----
Then I can use it throughout my application.
my $constant = MyApp::Constant->instance;
sub foo_track_type_count {
return shift->tracks( {
track_type => $constant->track_type_foo,
})->count;
}
----
regards
Ian
On 23/04/2010 22:46, Bill Moseley wrote:
My music DB has CDs and each CD has many tracks.
In my CD source class I have helper methods.
sub total_track_count {
return shift->tracks->count;
}
And for the sake of the example, I have a "track_type".
sub foo_track_type_count {
return shift->tracks( { track_type => 1 } )->count;
}
sub bar_track_type_count {
return shift->tracks( { track_type => { -in => [2,3] } } )->count;
}
I'm finding I need to know the track_type IDs in other code -- for
example, in validation code. I don't want to hard-code the track_type
ids all over the place. My question is how do you manage constants like
this?
One option is to have a constants module, i.e. "use MyApp::Const
'track_types'" that my result source uses. Then any other code that
needs those constants also uses MyApp::Const.
Another option would be to define the constants in the Track source.
sub bar_types { return [2,3] }
then back in the Cd class:
sub bar_track_type_count {
my $self = shift;
my $bar_types = $self->result_source->schema->resultset( 'Track'
)->result_class->bar_types;
return $self->tracks( { track_type => { -in => $bar_types } }
)->count;
}
How do you manage constants like this?
BTW -- Can't I get the result class w/o building a resultset? Something
like $schema->source( 'Track') ?
--
Bill Moseley
[email protected] <mailto:[email protected]>
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