Sluggi

Sluggi is a simple friendly_id-inspired slugging library for ActiveRecord models. It is faster than friendly_id (see below for benchmarks).

It provides basic slugs, slug history, and the ability to define multiple slug candidates.

Sluggi 1.x works with Rails 5.1+. Sluggi 0.5.x works with Rails 4.0-5.0.x. Make sure to view the 0.5-stable branch's Readme for those versions.

Install

Add this line to your Gemfile:

gem 'sluggi'

Add a string column named slug to any models you want to slug. You can generate a migration like so:

rails generate migration AddSlugToCats slug:string:uniq:index
rake db:migrate

To track slug history for any model, you must generate a migration to add the slugs table:

rails generate sluggi
rake db:migrate

Usage

Sluggi is Magic Free(tm). Each slugged model must:

Have a column named slug (see above).
Include the Sluggi::Slugged module
Override the slug_value method or the slug_candidates method.

Simple Slugged Model

Specify the slug value by defining #slug_value and #slug_value_changed?.

class Cat < ActiveRecord::Base
  include Sluggi::Slugged

  def slug_value
    name
  end

  def slug_value_changed?
    name_changed?
  end
end

cat = Cat.create(name: 'Tuxedo Stan')
cat.slug
=> 'tuxedo-stan'

cat.to_param
=> 'tuxedo-stan'

cat_path
=> 'cats/tuxedo-stan'

Cat.find_by_slug('tuxedo-stan')
=> cat

Model with Slugged History

To save slug history, include Sluggi::History. You get a slugs association. You can search for any slug in the history using .find_slug!.

You must also implement #saved_change_to_slug_value?.

class Cat < ActiveRecord::Base
  include Sluggi::Slugged
  include Sluggi::History

  def slug_value
    name
  end

  def slug_value_changed?
    name_changed?
  end

  def saved_change_to_slug_value?
    saved_change_to_name?
  end
end

cat = Cat.create(name: 'Tuxedo Stan')
cat.slug
=> 'tuxedo-stan'

cat.name = 'Tuxedo Bob'
cat.save
cat.slug
=> 'tuxedo-bob'

# use .find_slug! to search slug history:

Cat.find_slug!('tuxedo-bob')
=> cat
Cat.find_slug!('tuxedo-stan')
=> cat

# plain finders will not search history:

Cat.find_by_slug('tuxedo-bob')
=> cat

Cat.find_by_slug('tuxedo-stan')
=> RecordNotFound

Model with Slug Candidates

Override #slug_candidates to define cascading candidate values for slugs. This is useful to avoid uniqueness conflicts. Do not override #slug_value - the default implementation in Model will call #slug_candidates and works with or without History.

class Cat < ActiveRecord::Base
  include Sluggi::Slugged

  # The first unused value in the list is used.
  # Each item may be a value or a lambda.
  # Use a lambda to defer expensive unique value calculations.
  def slug_candidates
    [
      name,
      -> { "#{name}-#{Cat.count}" }
    ]
  end

  def slug_value_changed?
    name_changed?
  end
end

cat = Cat.create(name: 'Tuxedo Stan')
cat.slug
=> 'tuxedo-stan'

cat_2 = Cat.create(name: 'Tuxedo Stan')
cat_2.slug
=> 'tuxedo-stan-456'

Performance

Run the benchmark script: ruby bench.rb. This script is based on the benchmark script from friendly_id.

Here are some anecdotal results using ruby 2.5.3:

                                                  SLUGGI      FRIENDLY_ID
1) find (id) - direct ActiveRecord                0.092318    0.093049
2) find (in-table slug)                           0.102773    0.259542
3) find (in-table slug; using finders module)     0.098183    0.108248
4) find (external slug)                           0.670229    0.832791
5) insert (plain AR / no slug)                    0.345077    0.345105
6) insert (in-table-slug)                         0.666451    0.815505
7) insert (in-table-slug; using finders module)   0.668737    0.744433
8) insert (external slug)                         2.480790    2.849761

Notes:

Sluggi is at least 10% faster in every benchmark.

1) Baseline (does not use either gem) 2) 0.44x 3) 0.90x 4) 0.80x 5) Baseline (does not use either gem) 6) 0.82x 7) 0.90x 8) 0.87x