Plack - location of .psgi matters?

[richardhuxton]

Using plackup (or starman - presumably others too) with a .psgi file in a dir other than "$app/bin" fails. Steps to reproduce below:

$ cat /tmp/app.psgi
use Dancer;
use Plack;
load_app 'test1';

use Dancer::Config 'setting';
setting apphandler => 'PSGI';
Dancer::Config->load;

my $app1 = sub {
    my $env = shift;
    my $request = Dancer::Request->new( $env );
    Dancer->dance( $request );
};

Minimal file as above.

$ dancer -a test1
$ cp /tmp/app.psgi test1/bin/
$ mkdir test1/res
$ cp /tmp/app.psgi test1/res/

$ plackup test1/bin/app.psgi 
Subroutine Plack::Sandbox::test1_2fbin_2fapp_2epsgi::setting redefined at /usr/share/perl/5.10/Exporter.pm line 66.
 at test1/bin/app.psgi line 5
[29747]  core @0.000017> loading application test1 in /srv/Projects/oldford_db/perllib/lib/perl5/Dancer.pm l. 209
[29747]  core @0.000709> initializing appdir to: `/srv/Projects/oldford_db/src/tmp/test1' in /srv/Projects/oldford_db/perllib/lib/perl5/Dancer.pm l. 264
HTTP::Server::PSGI: Accepting connections at http://0:5000/
^C

$ plackup test1/res/app.psgi 
Subroutine Plack::Sandbox::test1_2fres_2fapp_2epsgi::setting redefined at /usr/share/perl/5.10/Exporter.pm line 66.
 at test1/res/app.psgi line 5
Error while loading test1/res/app.psgi: unable to load application test1 : Can't locate test1.pm in @INC (@INC contains: ...) at /srv/Projects/oldford_db/perllib/lib/perl5/Dancer/ModuleLoader.pm line 31.
 at test1/res/app.psgi line 3

If I then add the path to .../test1/lib to PERL5LIB it starts up, but something is still not right.

plackup test1/res/app.psgi 
Subroutine Plack::Sandbox::test1_2fres_2fapp_2epsgi::setting redefined at /usr/share/perl/5.10/Exporter.pm line 66.
 at test1/res/app.psgi line 5
HTTP::Server::PSGI: Accepting connections at http://0:5000/

Note the lack of "core..." debugging lines about "loading application" or "initializing appdir".

Add the following line to the bottom of test1.pm

debug "app = " . config->{appname};

Running with bin/app.psgi give the debug line you would expect, but res/app.psgi gives a "uninitialized value" warning showing the config hasn't been loaded.

Platform: linux, perl 5.10.0, latest dancer and plack

[alexkalderimis]

I noticed this too after an upgrade, and had to move the script out of a script directory into bin

[xsawyerx]

I think the problems stems from us trying to understand your application structure, and it does that by looking for a 'bin' directory. This is probably not the best practice.

I'll look into it tomorrow.

[richardhuxton]

On 1 August 2011 20:39, xsawyerx < [email protected]>wrote:

I think the problems stems from us trying to understand your application structure, and it does that by looking for a 'bin' directory. This is probably not the best practice

If it just dies with a meaningful error message, I think that will help a lot. Something like: "Unable to load config - checked: /path/dancer/tried based on .psgi path of /path/to/psgi"

When I first came across this, I'd done a lot of tidying on the project, but none of it terribly complex and I couldn't figure out why it wouldn't start any more.

That plus a way to explicitly tell Dancer where the app dir is would be fine. It's difficult to see how you can improve much on your current auto-guessing. I put the .psgi in $APPDIR/res but it could have easily been $APPDIR/res/development which makes it difficult to come up with heuristics that aren't just going to make things more confusing when they go wrong.

Richard Huxton