[dancer-users] Call to all Dancer2 plugin writers

[Yanick Champoux]

Hi all,

Underneath the surface, I've been toiling away at a new plugin system
for Dancer2. This new system aims at fixing a few of the thorny issues
of the current one, and add a wee bit of unicorn dust to the mix.

## For plugin users, the changes are:

    * No change! The new plugins will be called the same way
        as the old ones -- it'll be transparent to you if a
        plugin is new gen or old gen. Isn't that music to your
        ears, or what? :-)

    * No change! Plugins using the new system can work side-by-side
        with original plugins. It's all really transparent to you.
        Relax, we're taking care of everything. :-)

## For plugin writers, the changes are:

    * The new system inherit from Dancer2::Plugin2 (yes, I know, we just
        loooove that '2' digit around here...).

    * The new system is much more OO-based, which so far makes for
	cleaner, easier to write plugins.

    * The new system doesn't export the Dancer keywords into the plugin
        namespace. It removes a little bit of the sugar (you'll have to
        do `$self->app->request` instead of `request()` inside
        the plugin module), but it makes much more explicit what is the
        plugin class, and what is the plugin instance associated
	with an app.

    * Plugin can now use other plugins!

    * The list of plugin instances are also kept as an attribute in
	the app object, which makes introspection possible (a
	plugin, for example, can check if other plugin A is
	already loaded or not and do things in consequence).


## What do I want from you?

Before unleashing D2::P2, it needs to be tested. Racke already migrated
two of his plugins to D2::P2
(https://github.com/PerlDancer/Dancer2/wiki/Plugins-migrated-to-D2::P2).
I would like for all of you to try to migrate your plugins, and report
if it was a success, or if you uncovered some sore points.

How to do that? I'm glad you asked:

1. clone and use the Dancer2 branch at
https://github.com/yanick/Dancer2/tree/plugins-yanick

2. read the D2::P2 docs (`perldoc lib/Dancer2/Plugin2`)

3. if docs are not sufficient, check examples (`/t/plugins2-*`) and the
    already-ported modules at bullet #5 below.

4. report all problems, head-scratchers, suggestions, etc to
    https://github.com/PerlDancer/Dancer2/pull/1010#issuecomment-147376270

5. you ported the plugin and all works? Post your victory to the PR
dicussion
    at #4, and add your plugin to the list at
    https://github.com/PerlDancer/Dancer2/wiki/Plugins-migrated-to-D2::P2
    (that's important, I'll set up a job to test any new tweaks on 	
   D2::P2 to all the converted modules)

And, of course, you have questions or anything, please feel free to hit
me with'em.

Joy,
`/anick