creating_a_pageflow_plugin_rails_engine.md

Creating a Pageflow Plugin Rails Engine

Generate a New Gem

You'll have to distribute Pageflow plugins as a Rubygem; either if you mean to share it with others like you, or keep the code private. The easiest way to go about this is to generate a gem, and then add the Rails Engine parts in later.

$ bundle gem some_plugin # your gem name will be different!

Fill in the missing fields in the gemspec that's created for you. While you're in there, add pageflow as a dependency:

# some_plugin.gemspec
spec.add_dependency 'pageflow', '~> x.y'
spec.add_dependency 'pageflow-public-i18n', '~> 1.0'

Where x is the current major and y is the minimal required minor version of Pageflow your plugin depends on. If your gem supports multiple major versions, specify an explicit range. For example, if the latest released Pageflow version is 13.3 and your plugin supports all versions equal to or above 12.1:

# some_plugin.gemspec
spec.add_dependency 'pageflow', ['>= 12.1', '< 14]'

Always use a pessimistic approach, excluding the next major version to prevent your plugin from breaking applications. Explicitly check that breaking changes in new major version releases do not effect your plugin before extending the range.

Rails Engine

Require the engine from your main file:

# lib/some_plugin.rb`
require some_plugin/engine'

And add it:

# lib/some_engine/engine.rb
require 'rails/engine'

module SomePlugin
  class Engine < ::Rails::Engine
    isolate_namespace SomePlugin

    # By default, locales from subdirectories are ignored
    config.i18n.load_path += Dir[config.root.join('config', 'locales', '**', '*.yml').to_s]
  end
end