Hi Trevor,
Many thanks for clarifying that. I guess I was hoping for some reliable
and predictable outcome for ambiguous requests but it seems the
statement "Don't do this" in the URL Path handling section does indeed
sum it up! And although it does not explicitly mention chained actions,
I presume any URL path ambiguity should/must be avoided.
What I was trying to achieve was a catch-all facility for requests other
than application defined actions, up to root level (i.e. for
user-specified URLs which are then looked up in a database). For the
life of me I can't remember why I avoided using the "default" action to
achieve this, probably because I thought being more specific (even just
by using a wildcard chain) was the most appropriate way to approach it
and more structured.
I presume then, that having a /*/... wildcard action to catch everything
else is not advisable? Is using the default action the preferred method
then to allow for unknown/dynamic URLs where an application defined
action is unavailable?
Thank you
Nick
On 27/02/13 22:34, Trevor Leffler wrote:
Hi Nick,
The best answer I've been able to find is "Don't Do This" from here:
https://metacpan.org/module/Catalyst::Manual::Intro#URL-Path-Handling
"Beware! If you write two matchers, that match the same path, with the
same specificity (that is, they match the same quantity of the path),
there's no guarantee which will actually get called."
So you're right in your confusion with the scenario you wrote up: why
do action0 and actionx get matched, but action1 is ignored in favor of
(:Chained) pages? Kieren's answer sort of side-stepped the issue by
inferring that all this goes away when you use the same matching
system, :Chained. By leveling the playing field it all works as you
would expect. I just (re-)skimmed the dwarves example, and
unfortunately it doesn't explicitly say *not* to mix :Chained with
other dispatch types.
The Manual's summary statement above might also have been: "Once you
go :Chained, go :Chained all the way." Or at least don't have a
wildcard chained action like pages() along with non-chained actions
and expect things to work predictably... ;)
--Trevor
On 02/27/2013 01:20 PM, Nick Anderson wrote:
Hi,
please could someone explain how Catalyst determines the precedence of
actions, specifically in relation to the following simple chained
example. It doesn't behave in the way I would expect for requests
numbered 4 and 6:
1. http://127.0.0.1:3001/action0 => Matched action 0
2. http://127.0.0.1:3001/action0/abc => Matched XPages / pages
3. http://127.0.0.1:3001/action1 => Matched XPages / pages
4. http://127.0.0.1:3001/action1/abc => Matched XPages / pages
5. http://127.0.0.1:3001/actionx => Matched action x
6. http://127.0.0.1:3001/actionx/abc => Matched XPages / pages
The controllers are detailed below:
package TestApp::Controller::Root;
use Moose;
use namespace::autoclean;
BEGIN { extends 'Catalyst::Controller' }
__PACKAGE__->config(namespace => '');
sub site_base :Chained :PathPart('') :CaptureArgs(0) {
my ($self,$c ) = @_;
}
sub action0 :Path('action0') :Args(0) {
my ($self,$c ) = @_;
$c->response->body( "Matched action 0" );
}
sub action1 :Path('action1') :Args(1) {
my ($self,$c ) = @_;
$c->response->body( "Matched action 1" );
}
sub actionx :Path('actionx') :Args() {
my ($self,$c ) = @_;
$c->response->body( "Matched action x" );
}
sub end : ActionClass('RenderView') {}
__PACKAGE__->meta->make_immutable;
1;
package TestApp::Controller::XPages;
use Moose;
use namespace::autoclean;
BEGIN {extends 'Catalyst::Controller'; }
sub base : Chained( '/site_base' ) : PathPart('') : CaptureArgs( 1 ) {
my ( $self, $c ) = @_;
}
sub pages : Chained( 'base' ) : PathPart('') : Args() {
my ( $self, $c ) = @_;
$c->response->body('Matched XPages / pages');
}
__PACKAGE__->meta->make_immutable;
1;
Thanks for any help you can give
Nick Anderson
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_______________________________________________
List: [email protected]
Listinfo: http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/catalyst
Searchable archive:
http://www.mail-archive.com/[email protected]/
Dev site: http://dev.catalyst.perl.org/
_______________________________________________
List: [email protected]
Listinfo: http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/catalyst
Searchable archive: http://www.mail-archive.com/[email protected]/
Dev site: http://dev.catalyst.perl.org/
