Using I18n and Draper to Render Database Attributes Blog Post

1.html.erb

# Show a user-friendly version of our identifier
Status: <%= current_user.status.humanize %>

# Now we need to customize some of them, use I18n
Status: <%= t current_user.status, default: current_user.status.humanize %>

# But that's polluting our I18n namespace
Status: <%= t :"user.status.#{ current_user.status }", default: current_user.status.humanize %>

# Ok, this is getting out of hand, lets refactor this to the model
Status: <%= current_user.status_string %>

# This breaks down when you need to render the select field to edit this user
<%= form.input :status, collection: User::STATUSES.map { |s| [User.new(status: s).status_string, s] } %>

# So, how 'bout a helper
Status: <%= humanize_with_i18n current_user.status, %(user status) %>

# Not too bad
<%= form.input :status, collection: User::STATUSES.map { |s| [humanize_with_i18n(s), s] } %>

# Ah, this is a bit better
<%= form.input :status, collection: user_roles_for_select %>

2.rb

class User < ActiveRecord::Base
  # ...
  def status_string
    I18n.t status, scope: %w(user status), default: status.humanize
  end

  def another_thing_string
    I18n.t ...
  # ... 
end

# Or something like:

module UserHelper
  def humanize_with_i18n(string, scope = [])
    I18n.t string, scope: scope, default: string.humanize
  end

  # The method prefix tells me that this should be in an object
  # But it doesn't belong in our model, does it?
  def user_roles_for_select
    User::STATUSES.map { |s| [humanize_with_i18n(s), s] }
  end
end

3.rb

class UserDecorator < ApplicationDecorator
  decorates :user

  def status
    # self.model gives us the User
    self.class.humanize_with_i18n(:status, model.status)
  end

  # This could be moved to ApplicationDecorator (or ApplicationHelper),
  # but is shown here for simplicity.
  def self.humanize_with_i18n(attribute, value)
    I18n.t value, scope: ['user', attribute], default: value
  end

  def self.status_options
    User::STATUSES.map { |s| [humanize_with_i18n(:status, s), s] }
  end
end

4.html.erb

Status: <%= current_user.decorator.status %>

<%= form.input :status, collection: UserDecorator.status_options %>

5.rb

class UserDecorator < ApplicationDecorator
  decorates :user
  humanizes :status

  def self.status_options
    options_for_select_with_i18n :status, model_class::STATUS_OPTIONS
  end
end

6.html.erb

Status: <%= current_user.status %>

<%= form.input :status, collection: UserDecorator.status_options %>