MerbScrewUnit

A slice for the Merb framework.

merb_screw_unit |– LICENSE |– README |– Rakefile [1] |– TODO |– app [2] | |– controllers | | |– application.rb | | ‘– main.rb | |– helpers | | `– application_helper.rb | `– views | |– layout | | `– merb_screw_unit.html.erb [3] | `– main | `– index.html.erb |– lib | |– merb_screw_unit | | |– merbtasks.rb [4] | | `– slicetasks.rb [5] | `– merb_screw_unit.rb [6] |– log | `– merb_test.log |– public [7] | |– javascripts | | `– master.js | `– stylesheets | `– master.css |– spec [8] | |– merb_screw_unit_spec.rb | |– controllers | | `– main_spec.rb | `– spec_helper.rb `– stubs [9]

`-- app
    `-- controllers
        |-- application.rb
        `-- main.rb

  1. Rake tasks to package/install the gem - edit this to modify the manifest.

  2. The slice application: controllers, models, helpers, views.

  3. The default layout, as specified in Merb::Slices::config[:layout] change this to :application to use the app’s layout.

  4. Standard rake tasks available to your application.

  5. Your custom application rake tasks.

  6. The main slice file - contains all slice setup logic/config.

  7. Public assets you (optionally) install using rake slices:merb_screw_unit:install

  8. Specs for basis slice behaviour - you usually adapt these for your slice.

  9. Stubs of classes/views/files for the end-user to override - usually these mimic the files in app/ and/or public/; use rake slices:merb_screw_unit:stubs to get started with the override stubs. Also, slices:merb_screw_unit:patch will copy over views to override in addition to the files found in /stubs.

To see all available tasks for MerbScrewUnit run:

rake -T slices:merb_screw_unit

Instructions for installation:

file: config/init.rb

# add the slice as a regular dependency

dependency ‘merb_screw_unit’

# if needed, configure which slices to load and in which order

Merb::Plugins.config = { :queue => [“MerbScrewUnit”, …] }

# optionally configure the plugins in a before_app_loads callback

Merb::BootLoader.before_app_loads do

Merb::Slices::config[:merb_screw_unit][:option] = value

end

file: config/router.rb

# example: /merb_screw_unit/:controller/:action/:id

r.add_slice(:MerbScrewUnit)

# example: /foo/:controller/:action/:id

r.add_slice(:MerbScrewUnit, ‘foo’) # same as :path => ‘foo’

# example: /:lang/:controller/:action/:id (with :a param set)

r.add_slice(:MerbScrewUnit, :path => ‘:lang’, :params => { :a => ‘b’ })

# example: /:controller/:action/:id

r.slice(:MerbScrewUnit)

Normally you should also run the following rake task:

rake slices:merb_screw_unit:install

You can put your application-level overrides in:

host-app/slices/merb_screw_unit/app - controllers, models, views …

Templates are located in this order:

  1. host-app/slices/merb_screw_unit/app/views/*

  2. gems/merb_screw_unit/app/views/*

  3. host-app/app/views/*

You can use the host application’s layout by configuring the merb_screw_unit slice in a before_app_loads block:

Merb::Slices.config = { :layout => :application }

By default :merb_screw_unit is used. If you need to override stylesheets or javascripts, just specify your own files in your layout instead/in addition to the ones supplied (if any) in host-app/public/slices/merb_screw_unit.

In any case don’t edit those files directly as they may be clobbered any time rake merb_screw_unit:install is run.

About Slices

Merb-Slices is a Merb plugin for using and creating application ‘slices’ which help you modularize your application. Usually these are reuseable extractions from your main app. In effect, a Slice is just like a regular Merb MVC application, both in functionality as well as in structure.

When you generate a Slice stub structure, a module is setup to serve as a namespace for your controller, models, helpers etc. This ensures maximum encapsulation. You could say a Slice is a mixture between a Merb plugin (a Gem) and a Merb application, reaping the benefits of both.

A host application can ‘mount’ a Slice inside the router, which means you have full over control how it integrates. By default a Slice’s routes are prefixed by its name (a router :namespace), but you can easily provide your own prefix or leave it out, mounting it at the root of your url-schema. You can even mount a Slice multiple times and give extra parameters to customize an instance’s behaviour.

A Slice’s Application controller uses controller_for_slice to setup slice specific behaviour, which mainly affects cascaded view handling. Additionaly, this method is available to any kind of controller, so it can be used for Merb Mailer too for example.

There are many ways which let you customize a Slice’s functionality and appearance without ever touching the Gem-level code itself. It’s not only easy to add template/layout overrides, you can also add/modify controllers, models and other runtime code from within the host application.

To create your own Slice run this (somewhere outside of your merb app):

$ merb-gen slice <your-lowercase-slice-name>