Sample Routes and Links with Rails 3 in the console

routes_link_to_in_rails_console.rb

# create new rails app
rails new routes_and_stuff
cd routes_and_stuff

# generate a user scaffold
rails generate scaffold user
bundle exec rake db:migrate

# checkout routes
bundle exec rake routes

# test some in the console
rails console
puts new_user_path
# => NameError: undefined local variable or method `new_user_path' for main:Object

# we need to include the routes module
include Rails.application.routes.url_helpers
puts new_user_path
# => /users/new
# => nil 

# much better, now lets try testing a link_to
link_to 'New User', new_user_path
# => NoMethodError: undefined method `link_to' for main:Object

# need the module that contains link_to
include ActionView::Helpers
link_to 'New User', new_user_path

# => SystemStackError: stack level too deep from ... Maybe IRB bug!!
# ok, a road I do not want to go down, lets do this the easy way

# you might need to exit and re-launch console, then...
class LinkHelper; include ActionView::Helpers; end
helper = LinkHelper.new
helper.link_to 'New User', new_user_path
# => "<a href=\"/users/new\">New User</a>"
helper.link_to 'Users', users_path
# => "<a href=\"/users\">Users</a>" 

# now we can test out some stuff, like request the same page with .csv extension
params = { :email => "%@testing.com", :is_active => true }
helper.link_to 'Users CSV Export', users_path(params.merge(:format => :csv))
# => "<a href=\"/users.csv?email=%25%40testing.com&amp;is_active=true\">Users CSV Export</a>" 

# http://house9.blogspot.com/2011/11/sample-routes-and-links-with-rails-3-in.html