Create pretty URLs using FriendlyId

Gemfile

@@ -25,6 +25,7 @@ gem 'figaro',                          '~> 1.1', '>= 1.1.1'
 gem 'gravatar_image_tag',              '~> 1.2'
 gem 'inline_svg',                      '~> 1.3', '>= 1.3.1'
 gem 'faker',                           '~> 1.8', '>= 1.8.7'
+gem 'friendly_id',                     '~> 5.2', '>= 5.2.4'
 
 # Used for bulk inserting data into database using ActiveRecord.
 gem 'activerecord-import',             '~> 0.23.0'

Gemfile.lock

@@ -140,6 +140,8 @@ GEM
     figaro (1.1.1)
       thor (~> 0.14)
     formatador (0.2.5)
+    friendly_id (5.2.4)
+      activerecord (>= 4.0.0)
     geocoder (1.4.7)
     globalid (0.4.1)
       activesupport (>= 4.2.0)
@@ -401,6 +403,7 @@ DEPENDENCIES
   devise (~> 4.4, >= 4.4.3)
   faker (~> 1.8, >= 1.8.7)
   figaro (~> 1.1, >= 1.1.1)
+  friendly_id (~> 5.2, >= 5.2.4)
   geocoder (~> 1.4, >= 1.4.5)
   gravatar_image_tag (~> 1.2)
   guard (= 2.14.0)

app/models/event.rb

@@ -1,4 +1,7 @@
 class Event < ApplicationRecord
+  include FriendlyId
+  friendly_id :slug_candidates, use: :scoped, scope: :group
+
   include Storext.model
 
   store_attributes :updated_fields do
@@ -20,7 +23,7 @@ class Event < ApplicationRecord
 
   delegate :place_name, :street1, :street2, :city,
            :state, :post_code, :country,
-           :full_address, :full_address_changed?, to: :address
+           :full_address, :full_address_changed?, to: :address, allow_nil: true
 
   has_many :attendances, foreign_key: "attended_event_id"
   has_many :attendees, through: :attendances
@@ -62,12 +65,19 @@ def short_description
 
   private
 
-    def no_past_date
-      if start_date < Time.zone.now
-        errors.add(:start_date, "can't be in the past")
-      elsif end_date < start_date
-        errors.add(:start_date, "can't be later than end date")
-      end
+    def should_generate_new_friendly_id?
+      title_changed?
+    end
+
+    def slug_candidates
+      [
+        :title,
+        [:title, :date]
+      ]
+    end
+
+    def date
+      start_date.strftime("%b %d %Y")
     end
 
     def titleize_title
@@ -111,4 +121,12 @@ def store_updated_address
     def touch_group
       group.touch
     end
+
+    def no_past_date
+      if start_date < Time.zone.now
+        errors.add(:start_date, "can't be in the past")
+      elsif end_date < start_date
+        errors.add(:start_date, "can't be later than end date")
+      end
+    end
 end

app/models/group.rb

@@ -1,6 +1,9 @@
 class Group < ApplicationRecord
   include PgSearch
 
+  include FriendlyId
+  friendly_id :slug_candidates, use: :slugged
+
   resourcify
 
   before_save  :titleize_name
@@ -65,6 +68,27 @@ def remove_from_organizers(member)
 
   private
 
+    def should_generate_new_friendly_id?
+      name_changed?
+    end
+
+    def slug_candidates
+      [
+        :name,
+        [:name, :location],
+        [:name, :location, :owner_name],
+        [:name, :location, :owner_name, :owner_id]
+      ]
+    end
+
+    def owner_name
+      owner.name
+    end
+
+    def owner_id
+      owner.id
+    end
+
     def titleize_name
       self.name = name.titleize
     end

app/models/sample_event.rb

@@ -32,6 +32,7 @@ def build_event
       )
 
       @event.build_address(event_address)
+      @event.send(:set_slug)
 
       # We don't validate because we are not setting the image,
       # so it's going to use the default one set by EventImageUploader.

app/models/sample_group.rb

@@ -30,6 +30,8 @@ def create_group
         sample_group: true
       )
 
+      @group.send(:set_slug)
+
       # We don't validate because we are not setting the image,
       # so it's going to use the default one set by GroupImageUploader.
       @group.save(validate: false)

app/models/user.rb

@@ -4,6 +4,9 @@ class User < ApplicationRecord
   devise :database_authenticatable, :registerable, :confirmable,
          :recoverable, :rememberable, :trackable, :validatable
 
+  include FriendlyId
+  friendly_id :slug_candidates, use: :slugged
+
   before_save   :titleize_name
   before_update :titleize_location
   before_update :capitalize_bio
@@ -96,6 +99,17 @@ def upcoming_attended_events
 
   private
 
+    def should_generate_new_friendly_id?
+      name_changed?
+    end
+
+    def slug_candidates
+      [
+        :name,
+        [:name, :id]
+      ]
+    end
+
     def titleize_name
       self.name = name.titleize
     end

config/initializers/friendly_id.rb

@@ -0,0 +1,107 @@
+# FriendlyId Global Configuration
+#
+# Use this to set up shared configuration options for your entire application.
+# Any of the configuration options shown here can also be applied to single
+# models by passing arguments to the `friendly_id` class method or defining
+# methods in your model.
+#
+# To learn more, check out the guide:
+#
+# http://norman.github.io/friendly_id/file.Guide.html
+
+FriendlyId.defaults do |config|
+  # ## Reserved Words
+  #
+  # Some words could conflict with Rails's routes when used as slugs, or are
+  # undesirable to allow as slugs. Edit this list as needed for your app.
+  config.use :reserved
+
+  config.reserved_words = %w(new edit index session login logout users admin
+    stylesheets assets javascripts images)
+
+  # This adds an option to to treat reserved words as conflicts rather than exceptions.
+  # When there is no good candidate, a UUID will be appended, matching the existing
+  # conflict behavior.
+
+  # config.treat_reserved_as_conflict = true
+
+  #  ## Friendly Finders
+  #
+  # Uncomment this to use friendly finders in all models. By default, if
+  # you wish to find a record by its friendly id, you must do:
+  #
+  #    MyModel.friendly.find('foo')
+  #
+  # If you uncomment this, you can do:
+  #
+  #    MyModel.find('foo')
+  #
+  # This is significantly more convenient but may not be appropriate for
+  # all applications, so you must explicity opt-in to this behavior. You can
+  # always also configure it on a per-model basis if you prefer.
+  #
+  # Something else to consider is that using the :finders addon boosts
+  # performance because it will avoid Rails-internal code that makes runtime
+  # calls to `Module.extend`.
+  #
+  config.use :finders
+  #
+  # ## Slugs
+  #
+  # Most applications will use the :slugged module everywhere. If you wish
+  # to do so, uncomment the following line.
+  #
+  # config.use :slugged
+  #
+  # By default, FriendlyId's :slugged addon expects the slug column to be named
+  # 'slug', but you can change it if you wish.
+  #
+  # config.slug_column = 'slug'
+  #
+  # By default, slug has no size limit, but you can change it if you wish.
+  #
+  # config.slug_limit = 255
+  #
+  # When FriendlyId can not generate a unique ID from your base method, it appends
+  # a UUID, separated by a single dash. You can configure the character used as the
+  # separator. If you're upgrading from FriendlyId 4, you may wish to replace this
+  # with two dashes.
+  #
+  # config.sequence_separator = '-'
+  #
+  # Note that you must use the :slugged addon **prior** to the line which
+  # configures the sequence separator, or else FriendlyId will raise an undefined
+  # method error.
+  #
+  #  ## Tips and Tricks
+  #
+  #  ### Controlling when slugs are generated
+  #
+  # As of FriendlyId 5.0, new slugs are generated only when the slug field is
+  # nil, but if you're using a column as your base method can change this
+  # behavior by overriding the `should_generate_new_friendly_id?` method that
+  # FriendlyId adds to your model. The change below makes FriendlyId 5.0 behave
+  # more like 4.0.
+  # Note: Use(include) Slugged module in the config if using the anonymous module.
+  # If you have `friendly_id :name, use: slugged` in the model, Slugged module
+  # is included after the anonymous module defined in the initializer, so it
+  # overrides the `should_generate_new_friendly_id?` method from the anonymous module.
+  #
+  # config.use :slugged
+  # config.use Module.new {
+  #   def should_generate_new_friendly_id?
+  #     slug.blank? || <your_column_name_here>_changed?
+  #   end
+  # }
+  #
+  # FriendlyId uses Rails's `parameterize` method to generate slugs, but for
+  # languages that don't use the Roman alphabet, that's not usually sufficient.
+  # Here we use the Babosa library to transliterate Russian Cyrillic slugs to
+  # ASCII. If you use this, don't forget to add "babosa" to your Gemfile.
+  #
+  # config.use Module.new {
+  #   def normalize_friendly_id(text)
+  #     text.to_slug.normalize! :transliterations => [:russian, :latin]
+  #   end
+  # }
+end

db/migrate/20180517163813_create_friendly_id_slugs.rb

@@ -0,0 +1,22 @@
+migration_class =
+  if ActiveRecord::VERSION::MAJOR >= 5
+    ActiveRecord::Migration[4.2]
+  else
+    ActiveRecord::Migration
+  end
+
+class CreateFriendlyIdSlugs < migration_class
+  def change
+    create_table :friendly_id_slugs do |t|
+      t.string   :slug,           :null => false
+      t.integer  :sluggable_id,   :null => false
+      t.string   :sluggable_type, :limit => 50
+      t.string   :scope
+      t.datetime :created_at
+    end
+    add_index :friendly_id_slugs, :sluggable_id
+    add_index :friendly_id_slugs, [:slug, :sluggable_type], length: { slug: 140, sluggable_type: 50 }
+    add_index :friendly_id_slugs, [:slug, :sluggable_type, :scope], length: { slug: 70, sluggable_type: 50, scope: 70 }, unique: true
+    add_index :friendly_id_slugs, :sluggable_type
+  end
+end

db/migrate/20180517170138_add_slug_to_groups.rb

@@ -0,0 +1,6 @@
+class AddSlugToGroups < ActiveRecord::Migration[5.1]
+  def change
+    add_column :groups, :slug, :string
+    add_index :groups, :slug
+  end
+end

db/migrate/20180517190202_add_slug_to_events.rb

@@ -0,0 +1,6 @@
+class AddSlugToEvents < ActiveRecord::Migration[5.1]
+  def change
+    add_column :events, :slug, :string
+    add_index :events, :slug
+  end
+end

db/migrate/20180517212505_add_slug_to_users.rb

@@ -0,0 +1,6 @@
+class AddSlugToUsers < ActiveRecord::Migration[5.1]
+  def change
+    add_column :users, :slug, :string
+    add_index :users, :slug
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20180517084540) do
+ActiveRecord::Schema.define(version: 20180517212505) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -53,8 +53,22 @@
     t.bigint "group_id"
     t.jsonb "updated_fields", default: {}, null: false
     t.boolean "sample_event", default: false
+    t.string "slug"
     t.index ["group_id"], name: "index_events_on_group_id"
     t.index ["organizer_id"], name: "index_events_on_organizer_id"
+    t.index ["slug"], name: "index_events_on_slug"
+  end
+
+  create_table "friendly_id_slugs", id: :serial, force: :cascade do |t|
+    t.string "slug", null: false
+    t.integer "sluggable_id", null: false
+    t.string "sluggable_type", limit: 50
+    t.string "scope"
+    t.datetime "created_at"
+    t.index ["slug", "sluggable_type", "scope"], name: "index_friendly_id_slugs_on_slug_and_sluggable_type_and_scope", unique: true
+    t.index ["slug", "sluggable_type"], name: "index_friendly_id_slugs_on_slug_and_sluggable_type"
+    t.index ["sluggable_id"], name: "index_friendly_id_slugs_on_sluggable_id"
+    t.index ["sluggable_type"], name: "index_friendly_id_slugs_on_sluggable_type"
   end
 
   create_table "group_memberships", force: :cascade do |t|
@@ -77,7 +91,9 @@
     t.bigint "user_id"
     t.string "location"
     t.boolean "sample_group", default: false
+    t.string "slug"
     t.index ["location"], name: "index_groups_on_location"
+    t.index ["slug"], name: "index_groups_on_slug"
     t.index ["user_id"], name: "index_groups_on_user_id"
   end
 
@@ -141,8 +157,10 @@
     t.string "unconfirmed_email"
     t.boolean "sample_user", default: false
     t.boolean "admin", default: false
+    t.string "slug"
     t.index ["confirmation_token"], name: "index_users_on_confirmation_token", unique: true
     t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
+    t.index ["slug"], name: "index_users_on_slug"
   end
 
   create_table "users_roles", id: false, force: :cascade do |t|

test/controllers/events_controller_test.rb

@@ -64,8 +64,11 @@ class EventsControllerTest < ActionDispatch::IntegrationTest
 
     patch group_event_url(@group, @event), params: event_params_updated
 
+    group = Group.find(@group.id)
+    event = Event.find(@event.id)
+
     assert_emails_sent_to attendees_emails
-    assert_redirected_to group_event_url(@group, @event)
+    assert_redirected_to group_event_url(group, event)
   end
 
   test "should destroy event" do