There are a few useful plack middleware's that can help with day to day development of your catalyst application. In this article I'll be giving a quick example of how to set them up and a quick run down of the use. Nothing exciting, but it's useful stuff.

Plack::Middleware::Debug Plack::Middleware::Debug::CatalystStash

Plack::Middleware::Debug contains a collection of debug panels, even one for showing the contents of the Catalyst Log.

We can enable the middleware in the catalyst app, rather than in the psgi. That way we can do some tricks to only enable it for debug mode, or when running on certain hosts etc.

    package MyApp;
    use Moose;

    use Catalyst;

    __PACKAGE__->config(
        'psgi_middleware', [
            'Debug' => {panels => [
                'Memory',
                'Timer',
                'CatalystLog',
                'CatalystStash',
            ]},
        ],
    );

    __PACKAGE__->setup;

This will give us a panel on any page with a </body> tag and a content type of text/html the above panels, which can be used to see how much memory was used, how long a page request took, what was written to the catalyst log (not including the request log) and what is in the stash.

It's only simple, but it all helps.

There's a wide selection of Plack debug middlewares available, here's a few that are worth investigating.

Plack::Middleware::Debug::DBIC::QueryLog

Plack::Middleware::Debug::CatalystPluginCache

Plack::Middleware::Debug::Profiler::NYTProf

Plack::Middleware::Debug::W3CValidate

https://metacpan.org/search?q=plack+middleware+debug

You can see the code for this article at https://github.com/perl-catalyst/2013-Advent-Staging/tree/master/Plack-Debug

Mark Ellis email:nobody@cpan.org