FriendlyId Mobility

Mobility support for FriendlyId.

Add this line to your application's Gemfile:

gem 'friendly_id-mobility', '~> 1.0.4'

And then execute:

bundle

Then run the Mobility generator:

rails generate mobility:install

This will generate an initializer for Mobility. To ensure that FriendlyId sees changes correctly on attributes, enable (uncomment) the dirty plugin line in your Mobility configuration:

Mobility.configure do
  plugins do
    # ...
    dirty
    # ...
  end
end

Next, run the FriendlyId generator:

rails generate friendly_id

And migrate to generate Mobility and FriendlyId tables:

rake db:migrate

You're ready to go!

There are two ways to translate FriendlyId slugs with Mobility: with an untranslated base column (like the SimpleI18n module included with FriendlyId), and with a translated base column.

If you only want to translate the slug, include Mobility and translate the slug with whichever backend you want (here we're assuming the default KeyValue backend). Here, name is untranslated (so there is a column on the journalists table named name):

class Journalist < ActiveRecord::Base
  extend Mobility
  translates :slug

  extend FriendlyId
  friendly_id :name, use: :mobility
end

You can now save name and generate a slug, and update the slug in any locale using set_friendly_id

journalist = Journalist.create(name: "John Smith")
journalist.slug
#=> "john-smith"
journalist.set_friendly_id("Juan Fulano", :es)
journalist.save!
I18n.with_locale(:es) { journalist.friendly_id }
#=> "juan-fulano"

So the slug is translated, but the base attribute (name) is not.

You can also translate both slug and base attribute:

class Article < ActiveRecord::Base
  extend Mobility
  translates :slug, :title

  extend FriendlyId
  friendly_id :title, use: :mobility
end

In this case, title is translated, and its value in the current locale will be used to generate the slug in this locale:

article = Article.create(title: "My Foo Title")
article.title
#=> "My Foo Title"
article.slug
#=> "my-foo-title"
Mobility.locale = :fr
article.title = "Mon titre foo"
article.save
article.slug
#=> "mon-titre-foo"
Mobility.locale = :en
article.slug
#=> "my-foo-title"

The Mobility i18n scope is mixed into the friendly scope for models which use: :mobility, so you can find translated slugs just like you would an untranslated one:

Mobility.locale = :en
Article.friendly.find("my-foo-title")
#=> #<Article id: 1 ...>
Mobility.locale = :fr
Article.friendly.find("mon-titre-foo")
#=> #<Article id: 1 ...>

Note that this gem is not compatible with the finders add-on; using both together will lead to unexpected results. To use these finder methods, you will have to remove finders and explicitly call friendly.find, as above.

To use the FriendlyId history module, use use: [:history, :mobility] when calling friendly_id from your model:

class Article < ActiveRecord::Base
  extend Mobility
  translates :slug, :title

  extend FriendlyId
  friendly_id :title, use: [:history, :mobility]
end

It is important to have :history before :mobility here, since the Mobility module looks for the presence of the history module and only adds necessary overrides if history has been enabled (so the reverse order will not work).

To use the history feature, you must add a locale column to your friendly_id_slugs table, which you can do with the friendly_id_mobility generator:

rails generate friendly_id_mobility

Then run the generated migration with rake db:migrate.

The gem is available as open source under the terms of the MIT License.