StaleChat error

lib/telegram/bot.rb

@@ -7,6 +7,25 @@ module Telegram
     class Error < StandardError; end
     class NotFound < Error; end
 
+    # Error class for events when chat is not available anymore for bot.
+    # While Telegram has same error codes for different messages and there is no
+    # official docs for this error codes it uses `description` to
+    # check response.
+    class StaleChat < Error
+      DESCRIPTIONS = [
+        'bot was kicked',
+        "can't write to",
+        'group chat is deactivated',
+      ].freeze
+
+      class << self
+        def match_response?(response)
+          description = response['description'].to_s
+          DESCRIPTIONS.any? { |x| description[x] }
+        end
+      end
+    end
+
     autoload :Client,             'telegram/bot/client'
     autoload :ClientStub,         'telegram/bot/client_stub'
     autoload :Middleware,         'telegram/bot/middleware'