Use Omniauthable user model with admin role

db/migrate/20190203145552_devise_create_users.rb

@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+class DeviseCreateUsers < ActiveRecord::Migration[5.2]
+  def change
+    create_table :users do |t|
+      ## OmniAuth-able
+      t.string :provider, null: false
+      t.string :uid, null: false
+
+      ## User role
+      t.integer :role, default: 0
+
+      ## Rememberable
+      t.datetime :remember_created_at
+
+
+      ## Database authenticatable
+      # t.string :email,              null: false, default: ""
+      # t.string :encrypted_password, null: false, default: ""
+
+      ## Recoverable
+      # t.string   :reset_password_token
+      # t.datetime :reset_password_sent_at
+
+
+      ## Trackable
+      # t.integer  :sign_in_count, default: 0, null: false
+      # t.datetime :current_sign_in_at
+      # t.datetime :last_sign_in_at
+      # t.string   :current_sign_in_ip
+      # t.string   :last_sign_in_ip
+
+      ## Confirmable
+      # t.string   :confirmation_token
+      # t.datetime :confirmed_at
+      # t.datetime :confirmation_sent_at
+      # t.string   :unconfirmed_email # Only if using reconfirmable
+
+      ## Lockable
+      # t.integer  :failed_attempts, default: 0, null: false # Only if lock strategy is :failed_attempts
+      # t.string   :unlock_token # Only if unlock strategy is :email or :both
+      # t.datetime :locked_at
+
+
+      t.timestamps null: false
+    end
+
+    # add_index :users, :email,                unique: true
+    # add_index :users, :reset_password_token, unique: true
+    # add_index :users, :confirmation_token,   unique: true
+    # add_index :users, :unlock_token,         unique: true
+  end
+end

db/migrate/20190203150923_add_name_to_users.rb

@@ -0,0 +1,5 @@
+class AddNameToUsers < ActiveRecord::Migration[5.2]
+  def change
+    add_column :users, :name, :string
+  end
+end

db/migrate/20190203164629_drop_admins.rb

@@ -0,0 +1,8 @@
+class DropAdmins < ActiveRecord::Migration[5.2]
+  def up
+    drop_table :admins
+  end
+  def down
+    fail ActiveRecord::IrreversibleMigration
+  end
+end