v0.1.0

lib/telegram/bot/updates_poller.rb

@@ -0,0 +1,88 @@
+module Telegram
+  class Bot
+    # Supposed to be used in development environments only.
+    class UpdatesPoller
+      class << self
+        @@instances = {} # rubocop:disable ClassVars
+
+        def instances
+          @@instances
+        end
+
+        # Create, start and add poller instnace to tracked instances list.
+        def add(bot, controller)
+          new(bot, controller).tap { |x| instances[bot] = x }
+        end
+
+        def start(bot_id, controller = nil)
+          bot = bot_id.is_a?(Symbol) ? Telegram.bots[bot_id] : Bot.wrap(bot_id)
+          instance = controller ? new(bot, controller) : instances[bot]
+          raise "Poller not found for #{bot_id.inspect}" unless instance
+          instance.start
+        end
+      end
+
+      DEFAULT_TIMEOUT = 5
+
+      attr_reader :bot, :controller, :timeout, :offset, :logger, :running, :reload
+
+      def initialize(bot, controller, **options)
+        @logger = options.fetch(:logger) { defined?(Rails) && Rails.logger }
+        @bot = bot
+        @controller = controller
+        @timeout = options.fetch(:timeout) { DEFAULT_TIMEOUT }
+        @offset = options[:offset]
+        @reload = options.fetch(:reload) { defined?(Rails) && Rails.env.development? }
+      end
+
+      def log(&block)
+        logger.info(&block) if logger
+      end
+
+      def start
+        return if running
+        @running = true
+        log { 'Started bot poller.' }
+        while running
+          begin
+            fetch_updates do |update|
+              controller.dispatch(bot, update)
+            end
+          rescue Interrupt
+            @running = false
+          rescue => e
+            logger.error { ([e.message] + e.backtrace).join("\n") } if logger
+          end
+        end
+        log { 'Stop polling bot updates.' }
+      end
+
+      def stop
+        return unless running
+        log { 'Killing polling thread.' }
+        @running = false
+      end
+
+      def fetch_updates
+        response = bot.get_updates(offset: offset, timeout: timeout)
+        return unless response['ok'] && response['result'].any?
+        reload! do
+          response['result'].each do |update|
+            @offset = update['update_id'] + 1
+            yield update
+          end
+        end
+      rescue Timeout::Error # rubocop:disable HandleExceptions
+      end
+
+      def reload!
+        return yield unless reload
+        ActionDispatch::Reloader.prepare!
+        if controller.is_a?(Class) && controller.name
+          @controller = Object.const_get(controller.name)
+        end
+        yield.tap { ActionDispatch::Reloader.cleanup! }
+      end
+    end
+  end
+end