This slide reminds some issues you may want to know about rails 3 generator.

1. Rails 3 app auto-generator
Tse-Ching Ho
2010/08/17 Ruby-Tuesday | ruby.tw

2. It’s bored to always write
the same codes.

3. Who needs auto generator?

4. NO, Rails Newbies!!
Before you do it,
You must understand what you are doing.
You should play on local branch (git/mercurial).
You should know each pieces of codes (Don’t generate trash).
You need consistency between projects.
You want be a time saver (Stop copy, paste and verify).
You type codes as slow as me :(

5. What should we do?

6. Modulate your codes
Maintainability is a critical thing for long life projects.
Reusability is valuable for programmers.
Modules are everywhere in rails 3. Use it!

7. Gemify your modules
Be a ruby gem producer
http://railscasts.com/episodes/218-making-generators-in-rails-3
jeweler --rspec --gemcutter my_awesome_gem
bundle gem my_awesome_gem
create my_awesome_gem/Gemfile
create my_awesome_gem/Rakefile
create my_awesome_gem/.gitignore
create my_awesome_gem/my_awesome_gem.gemspec
create my_awesome_gem/lib/my_awesome_gem.rb
create my_awesome_gem/lib/my_awesome_gem/version.rb
rake build
rake install
rake push

8. Update to Rails 3
Be familiar with APIs of thor and rails 3 generator
gsub_file 'public/stylesheets/blueprint/screen.css', /src/grid.png/, 'grid.png'
inject_into_file 'config/application.rb', "n config.middleware.use Rack::Tidyn", :before => " end
nendn"
Keep updated by force/skip overwrite option
rails generate responders:install -f

9. Live Demo

10. Issues

11. Bundler
Gemfile.lock should always keep updated in generators.
gem 'simple_form'
run 'bundle install'
run 'bundle update'
generate 'simple_form:install', '-s'
Use gems, don’t use git branch.
You should commit Gemfile.lock if you need consistency
between development and production environment.

12. JQuery
get 'http://github.com/rails/jquery-ujs/raw/master/src/rails.js', 'public/
javascripts/rails.js'
inject_into_file 'config/application.rb', "
config.action_view.javascript_expansions[:defaults] = %w(jquery jquery-ui rails)
n", :after => "# config.action_view.javascript_expansions[:defaults] = %w(jquery
rails)n", :verbose => false
jqueryui.com only keeps the latest one zip file!
http://jqueryui.com/download/jquery-ui-1.8.4.custom.zip

13. Customized templates
Rails.root/lib/templates/erb/scaffold/index.html.erb
config.generators.scaffold_controller = :responders_controller
config.generators do |g|
g.orm :active_record
g.template_engine :erb
g.integration_tool :rspec
g.test_framework :rspec
g.scaffold :stylesheets => false
end

14. Migration files
migration_template 'create_roles.rb', 'db/migrate/create_roles.rb'
# Implement the required interface for Rails::Generators::Migration.
def self.next_migration_number(dirname) #:nodoc:
@next_migration_number = if @next_migration_number
(@next_migration_number.to_i + 1).to_s
elsif ActiveRecord::Base.timestamped_migrations
Time.now.utc.strftime("%Y%m%d%H%M%S")
else
"%.3d" % (current_migration_number(dirname) + 1)
end
end
def migration_template(source, destination=nil, config={})
super
rescue Rails::Generators::Error => e
puts e
end

15. What else?
File.exist?
File path
source_root
destination_root
Rails.root
Customized configuration files (config/xxx.rb)

16. Make every practices as
generator!

17. Q&A

18. About me
Tse-Ching Ho (http://github.com/tsechingho)
Use Rails 2 since 2008
Senior R&D programmer in techbang.tw (T ) now

19. - END -