Install public_activity gem

Gemfile

@@ -13,6 +13,7 @@ gem 'font-awesome-rails'
 gem 'jbuilder', '~> 2.5'
 gem 'jquery-rails'
 gem 'pg', '~> 0.18'
+gem 'public_activity'
 gem 'puma', '~> 3.0'
 gem 'rails', '~> 5.0.1'
 gem 'rainbow', '>= 2.1.0', '< 2.2.0' # workaround for bundler errors

Gemfile.lock

@@ -162,6 +162,11 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
       slop (~> 3.4)
+    public_activity (1.5.0)
+      actionpack (>= 3.0.0)
+      activerecord (>= 3.0)
+      i18n (>= 0.5.0)
+      railties (>= 3.0.0)
     public_suffix (2.0.5)
     puma (3.6.2)
     rack (2.0.1)
@@ -327,6 +332,7 @@ DEPENDENCIES
   launchy
   listen (~> 3.0.5)
   pg (~> 0.18)
+  public_activity
   puma (~> 3.0)
   rails (~> 5.0.1)
   rails-assets-tether (>= 1.3.3)!
@@ -349,4 +355,4 @@ DEPENDENCIES
   web-console (>= 3.3.0)
 
 BUNDLED WITH
-   1.14.3
+   1.14.4

db/migrate/20170221091555_create_activities.rb

@@ -0,0 +1,24 @@
+# Migration responsible for creating a table with activities
+class CreateActivities < ActiveRecord::Migration
+  # Create table
+  def self.up
+    create_table :activities do |t|
+      t.belongs_to :trackable, polymorphic: true
+      t.belongs_to :owner, polymorphic: true
+      t.string  :key
+      t.text    :parameters
+      t.belongs_to :recipient, polymorphic: true
+
+      t.timestamps
+    end
+
+    add_index :activities, [:trackable_id, :trackable_type]
+    add_index :activities, [:owner_id, :owner_type]
+    add_index :activities, [:recipient_id, :recipient_type]
+  end
+
+  # Drop table
+  def self.down
+    drop_table :activities
+  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: 20_170_215_121_139) do
+ActiveRecord::Schema.define(version: 20_170_221_091_555) do
   # These are extensions that must be enabled in order to support this database
   enable_extension 'plpgsql'
 
@@ -21,13 +21,20 @@
     t.integer  'creator_id'
   end
 
-  create_table 'invites', force: :cascade do |t|
-    t.integer  'room_id'
-    t.integer  'sender_id'
+  create_table 'activities', force: :cascade do |t|
+    t.string   'trackable_type'
+    t.integer  'trackable_id'
+    t.string   'owner_type'
+    t.integer  'owner_id'
+    t.string   'key'
+    t.text     'parameters'
+    t.string   'recipient_type'
     t.integer  'recipient_id'
-    t.datetime 'created_at',   null: false
-    t.datetime 'updated_at',   null: false
-    t.index ['room_id'], name: 'index_invites_on_room_id', using: :btree
+    t.datetime 'created_at'
+    t.datetime 'updated_at'
+    t.index %w(owner_id owner_type), name: 'index_activities_on_owner_id_and_owner_type', using: :btree
+    t.index %w(recipient_id recipient_type), name: 'index_activities_on_recipient_id_and_recipient_type', using: :btree
+    t.index %w(trackable_id trackable_type), name: 'index_activities_on_trackable_id_and_trackable_type', using: :btree
   end
 
   create_table 'room_actions', id: false, force: :cascade do |t|
@@ -81,7 +88,6 @@
     t.index ['room_id'], name: 'index_users_on_room_id', using: :btree
   end
 
-  add_foreign_key 'invites', 'rooms'
   add_foreign_key 'room_actions', 'actions'
   add_foreign_key 'room_actions', 'rooms'
   add_foreign_key 'room_requests', 'rooms'