[Catalyst] Multiple DB, single instance of Cat

James R. Leu jleu at mindspring.com
Fri Sep 12 15:09:44 BST 2008

To get rid of the ACCEPT_CONTEXT redefined messages I modified that last
for loop in Catalyst::Model::DBIC::Schema::new() to be:

    foreach my $moniker ($self->schema->sources) {
        my $classname = "${class}::$moniker";
        if (!defined(*{"${classname}::ACCEPT_CONTEXT"})) {
            *{"${classname}::ACCEPT_CONTEXT"} = sub {

I'm not sure if it is the correct solution, but "it works for me".  It
would be nice to hear back from someone if this is truly a bad idea,
or maybe hints for better ways to solve the issue.


On Thu, Sep 11, 2008 at 11:58:31PM +0100, Nigel Stuckey wrote:
> Matt
> I stand corrected on DBIx! Yes, indeed I mean DBIx::Class.
> The code is in and works, but has a couple of issues. Firstly, it  
> creates new classes and carries out a DB connect every time there is a 
> request. Is there a way to make it more efficient by caching the classes 
> and DB connects once there is a successful authentication?
> Secondly, there are loads of 'ACCEPT_CONTEXT redefined' messages, one  
> per DB table defined to the DBIC model. When initialising, I have to  
> give the 'dynamic' model an initial configuration to allow Catalyst o  
> start.
> Once the code is working I will pop it on the wiki.
> cheers
> Nigel
> On 17 Aug 2008, at 8:08pm, Matt S Trout wrote:
>> On Fri, Aug 15, 2008 at 11:05:03AM +0100, Nigel Stuckey wrote:
>>> Another question about multiple databases.
>>> I have an existing application that uses a DBIx DB in the  
>>> conventional
>>> way: as a model initialised at run time. All great so far...
>> DBIx is the CPAN namespace for DBI extensions. There are hundres of
>> packages in there and you haven't told us which one of them you're  
>> using.
>> I'm going to assume you mean DBIx::Class but if you want to abbreviate
>> that please use 'DBIC' - it's really unfair to the authors of other
>> DBIx:: modules otherwise (compare to people saying "Linux 9" when they
>> actually mean "Red Hat Linux 9" or whatever :)
>>> However, I now need to make the application multi-organisation in the
>>> same instance of catalyst: users will select their organisation or
>>> repository when they login or it will be stored as a preference, etc.
>>> Due to the size of the repository, this is implemented as multiple
>>> databases. Thus a single running Catalyst instance will need to open
>>> several DBs sharing the same schema, dynamically after run time. Then
>>> it will have to close unused connections after a while.
>>> What is the best way to do this with DBIx and where is the best place
>>> to store the handles/class references? A key to the active DB can be
>>> stored in the session.
>> Something like the following (please write this up on the wiki once  
>> you've
>> got a working version, mine's typed straight into mutt and obviously
>> isn't -quite- complete :)
>> package MyApp::Model::DBIC;
>> use Moose;
>> extends 'Catalyst::Model::DBIC::Schema';
>> with 'Catalyst::Component::InstancePerContext';
>> sub build_per_context_instance {
>>   my ($self, $c) = @_;
>>   my $db_name = $c->session->{db_name};
>>   my $new = $self->new({ %$self });
>>   <do something here to make @connect_info from $db_name and config>
>>   $new->schema($self->schema->connect(@connect_info));
>>   return $new;
>> }
>> 1;
>> -- 
>>       Matt S Trout       Need help with your Catalyst or DBIx::Class 
>> project?
>>    Technical Director                    http://www.shadowcat.co.uk/ 
>> catalyst/
>>  Shadowcat Systems Ltd.  Want a managed development or deployment  
>> platform?
>> http://chainsawblues.vox.com/            http://www.shadowcat.co.uk/ 
>> servers/
>> _______________________________________________
>> List: Catalyst at lists.scsys.co.uk
>> Listinfo: http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/catalyst
>> Searchable archive: http://www.mail-archive.com/ 
>> catalyst at lists.scsys.co.uk/
>> Dev site: http://dev.catalyst.perl.org/
> _______________________________________________
> List: Catalyst at lists.scsys.co.uk
> Listinfo: http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/catalyst
> Searchable archive: http://www.mail-archive.com/catalyst@lists.scsys.co.uk/
> Dev site: http://dev.catalyst.perl.org/

James R. Leu
jleu at mindspring.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
Url : http://lists.scsys.co.uk/pipermail/catalyst/attachments/20080912/ddf0f62c/attachment.pgp

More information about the Catalyst mailing list