Merb Installing

I recently started updating an application I wrote called Easel (yes it's a CMS) to version 2.1 of Rails. It was originally written pre-1.0 Rails, so it needed some serious updates and I wanted to open source the application.

Today I talked with some co-workers bringing them up to speed on the 2.x updates as they had last used Rails somewhere around 1.1.6. While talking with them, the conversation led to competitors and my belief that Merb has great potential. I've loved the pluggable architecture and overall direction taken by Ezra and the Merb team from the beginning.

So, shortly after the meeting I decided to stop my update of Easel and migrate the application to Merb. I know what I'm after for functionality, I knew the code needed updating so I thought this was a great time to switch.

So, I'm going to post what I learn as I switch to Merb. This first post is about installing the gems, creating a basic app structure and adding one resource.

# Substitute vi for your favorite editor command
#
# --include-dependencies or -y is now default
#
$ sudo gem install merb

#
# output from gem install merb
#
Successfully installed merb-core-0.9.2
Successfully installed merb-action-args-0.9.2
Successfully installed merb-assets-0.9.2
Successfully installed merb-gen-0.9.2
Successfully installed merb-haml-0.9.2
Successfully installed merb-builder-0.9.2
Successfully installed merb-mailer-0.9.2
Successfully installed merb-parts-0.9.2
Successfully installed merb-cache-0.9.2
Successfully installed merb-more-0.9.2
Successfully installed merb-0.9.2
<snip>
#
# end output
#

#
# Install the Datamapper ORM
#
$ sudo gem install merb_datamapper 


#
# Create an application skeleton
#

$ merb-gen app easel

#
# output from merb-gen app easel
#
RubiGen::Scripts::Generate
create  app
create  app/controllers
create  app/helpers
create  app/views
create  app/views/exceptions
create  app/views/layout
create  autotest
create  config
create  config/environments
create  public
create  public/images
create  public/stylesheets
create  spec
create  app/controllers/application.rb
create  app/controllers/exceptions.rb
create  app/helpers/global_helpers.rb
create  app/views/exceptions/internal_server_error.html.erb
create  app/views/exceptions/not_acceptable.html.erb
create  app/views/exceptions/not_found.html.erb
create  app/views/layout/application.html.erb
create  autotest/discover.rb
create  autotest/merb.rb
create  autotest/merb_rspec.rb
create  config/rack.rb
create  config/router.rb
create  config/init.rb
create  config/environments/development.rb
create  config/environments/production.rb
create  config/environments/rake.rb
create  config/environments/test.rb
create  public/merb.fcgi
create  public/images/merb.jpg
create  public/stylesheets/master.css
create  spec/spec.opts
create  spec/spec_helper.rb
create  /Rakefile
#
# end output
#

$ cd easel

$ vi config/init.rb

#Uncomment for DataMapper ORM
use_orm :datamapper

$ cp config/database.yml.sample config/database.yml

$ vi config/database.yml

#
# Edit to your database settings
#

#
# if using mysql, install the DataObjects::Mysql Driver
#
$ sudo gem install do_mysql

# Output from gem install do_mysql
#
Building native extensions.  This could take a while...
Successfully installed data_objects-0.2.0
Successfully installed do_mysql-0.2.3
<snip>
#
# end output
#

# Let's run to make sure we can.  You should get the not_found.html.erb
# exception page.

$ merb

# merb defaults to port 4000 so go to:
#
# http://localhost:4000
#

#
# So, lets generate a resource (controller, model, view)
#

$ merb-gen resource page content:text permanent_url:string is_enabled:boolean is_featured:boolean show_in_footer:boolean

#
# Output from merb-gen command
#
dependency  model
exists    app
create    app/models
create    app/models/page.rb
dependency    merb_model_test
exists      spec
create      spec/models
create      spec/models/page_spec.rb
dependency  resource_controller
exists    app
exists    app/controllers
exists    app/helpers
exists    app/views
create    app/views/pages
create    app/controllers/pages.rb
create    app/helpers/pages_helper.rb
create    app/views/pages/edit.html.erb
create    app/views/pages/index.html.erb
create    app/views/pages/new.html.erb
create    app/views/pages/show.html.erb
dependency    merb_resource_controller_test
create      spec/controllers/
create      spec/helpers/
exists      spec
exists      spec/controllers
exists      spec/helpers
create      spec/views
create      spec/views/pages
create      spec/controllers/pages_spec.rb
create      spec/helpers/pages_helpers.rb
create      spec/views/pages/delete.html.erb_spec.rb
create      spec/views/pages/edit.html.erb_spec.rb
create      spec/views/pages/index.html.erb_spec.rb
create      spec/views/pages/new.html.erb_spec.rb
create      spec/views/pages/show.html.erb_spec.rb
#
# end output
#

#
# Check out the model, just for a looksee
#
$ vi app/models/page.rb

#
# Page model 
#
class Page < DataMapper::Base
  property :show_in_footer, :boolean
  property :is_featured, :boolean
  property :is_enabled, :boolean
  property :content, :text
  property :permanent_url, :string
end
#
# end page model
#

#
# Add pages to routes file
#
$ vi config/router.rb

#
# in Merb::Router.prepare do |r|
#

r.resources :pages

#
# Startup merb and access your new resource
#
# http://localhost:4000/pages
#

The resource generator just creates place holder files without any template form code like the Rails generator. From the Merb point of view, I completely understand. From the developer point of view, I'll have to write a more complete generator to save me some time.

There will be a lot more to come, but this post is super long already. :)