Add attribute TelegramBot#username

app/models/telegram_bot.rb

@@ -1,6 +1,13 @@
 # frozen_string_literal: true
 
 class TelegramBot < ApplicationRecord
+  USERNAME_RE = /\A[a-z_][a-z0-9_]*\z/i.freeze
+
   validates :secret, presence: true
   validates :api_token, presence: true
+
+  validates :username,
+            allow_nil: true,
+            presence:  true,
+            format:    USERNAME_RE
 end

app/views/telegram_bots/index.html.erb

@@ -11,6 +11,9 @@
         <th scope="col">
           <%= TelegramBot.human_attribute_name :api_token %>
         </th>
+        <th scope="col">
+          <%= TelegramBot.human_attribute_name :username %>
+        </th>
         <th scope="col"></th>
       </tr>
     </thead>
@@ -21,6 +24,8 @@
           <td scope="row"><%= telegram_bot.id %></td>
           <td><%= telegram_bot.secret %></td>
           <td><%= telegram_bot.api_token %></td>
+          <td><%= truncate telegram_bot.username, length: 20 %></td>
+          <td></td>
         </tr>
       <% end %>
     </tbody>

config/locales/activerecord/en.yml

@@ -72,6 +72,7 @@ en:
         id: ID
         secret: Secret
         api_token: API token
+        username: Username
       user:
         id: ID
         confirmation_sent_at: Confirmation sent at

config/locales/activerecord/ru.yml

@@ -72,6 +72,7 @@ ru:
         id: ID
         secret: Секрет
         api_token: Токен API
+        username: Имя пользователя
       user:
         id: ID
         confirmation_sent_at: Дата отправки подтверждения

db/migrate/20181207002553_add_username_to_telegram_bots.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddUsernameToTelegramBots < ActiveRecord::Migration[5.2]
+  def change
+    add_column :telegram_bots, :username, :string, index: true
+  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: 2018_12_06_224446) do
+ActiveRecord::Schema.define(version: 2018_12_07_002553) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -133,6 +133,7 @@ ActiveRecord::Schema.define(version: 2018_12_06_224446) do
     t.datetime "updated_at", null: false
     t.string "secret", null: false
     t.string "api_token", null: false
+    t.string "username"
   end
 
   create_table "user_omniauths", force: :cascade do |t|

spec/models/telegram_bot_spec.rb

@@ -7,4 +7,22 @@ RSpec.describe TelegramBot do
 
   it { is_expected.to validate_presence_of :secret }
   it { is_expected.to validate_presence_of :api_token }
+
+  describe '#username' do
+    def allow_value(*)
+      super.for :username
+    end
+
+    it { is_expected.to allow_value nil }
+
+    it { is_expected.not_to allow_value '' }
+    it { is_expected.not_to allow_value ' ' }
+    it { is_expected.not_to allow_value ' ' * rand(2..10) }
+
+    it { is_expected.to allow_value Faker::Internet.username nil, %w[_] }
+    it { is_expected.to allow_value 'foo123_456_BAR' }
+
+    it { is_expected.not_to allow_value Faker::Internet.email }
+    it { is_expected.not_to allow_value Faker::PhoneNumber.phone_number }
+  end
 end