Drop .context_handler, .context_to_action! methods

lib/telegram/bot/updates_controller/message_context.rb

@@ -2,51 +2,35 @@ module Telegram
   module Bot
     class UpdatesController
       # Allows to store context in session and treat next message according to this context.
+      #
+      # It provides `save_context` method to store method name
+      # to be used as action for next update:
+      #
+      #     def set_location!(*)
+      #       save_context(:set_location_from_message)
+      #       respond_with :message, text: 'Where are you?'
+      #     end
+      #
+      #     def set_location_from_messge(city = nil, *)
+      #       # update
+      #     end
+      #
+      #     # OR
+      #     # This will support both `/set_location city_name`, and `/set_location`
+      #     # with subsequent refinement.
+      #     def set_location!(city = nil, *)
+      #       if city
+      #         # update
+      #       else
+      #         save_context(:set_location!)
+      #         respond_with :message, text: 'Where are you?'
+      #       end
+      #     end
       module MessageContext
         extend ActiveSupport::Concern
 
         include Session
 
-        module ClassMethods
-          def context_handlers
-            @_context_handlers ||= {}
-          end
-
-          # Registers handler for context.
-          #
-          #     context_handler :rename do |*|
-          #       resource.update!(name: payload['text'])
-          #     end
-          #
-          #     # To run other action with all the callbacks:
-          #     context_handler :rename do |*words|
-          #       process(:rename, *words)
-          #     end
-          #
-          #     # Or just
-          #     context_handler :rename, :your_action_to_call
-          #     context_handler :rename # to call :rename
-          #
-          def context_handler(context = nil, action = nil, &block)
-            context &&= context.to_sym
-            if block
-              action = "_context_handler_#{context}"
-              define_method(action, &block)
-            end
-            context_handlers[context] = action || context
-          end
-
-          attr_reader :context_to_action
-
-          # Use it to use context value as action name for all contexts
-          # which miss handlers.
-          # For security reasons it supports only action methods and will
-          # raise AbstractController::ActionNotFound if context is invalid.
-          def context_to_action!
-            @context_to_action = true
-          end
-        end
-
         # Action to clear context.
         def cancel!
           # Context is already cleared in action_for_message
@@ -54,10 +38,6 @@ module Telegram
 
         private
 
-        # Context is read from the session to treat messages
-        # according to previous request.
-        attr_reader :context
-
         # Controller may have multiple sessions, let it be possible
         # to select session for message context.
         def message_context_session
@@ -68,13 +48,11 @@ module Telegram
         # it has higher priority than contextual action.
         def action_for_message
           val = message_context_session.delete(:context)
-          @context = val && val.to_sym
+          context = val && val.to_s
           super || context && begin
-            handler = handler_for_context
-            if handler
-              action_options = {type: :message_context, context: context}
-              [[handler, action_options], payload['text'].try!(:split) || []]
-            end
+            args = payload['text'].try!(:split) || []
+            action = action_for_message_context(context)
+            [[action, type: :message_context, context: context], args]
           end
         end
 
@@ -83,18 +61,16 @@ module Telegram
           message_context_session[:context] = context
         end
 
-        def handler_for_context
-          self.class.context_handlers[context] || self.class.context_to_action && begin
-            action_name = context.to_s
-            unless action_method?(action_name)
-              raise AbstractController::ActionNotFound,
-                "The action '#{action_name}' could not be set from context " \
-                "for #{self.class.name}. " \
-                'context_to_action! supports only action methods for security reasons. ' \
-                'If you need to call this action use context_handler for it.'
-            end
-            action_name
-          end
+        # Returns action name for message context. By default it's the same as context name.
+        # Raises AbstractController::ActionNotFound if action is not available.
+        # This differs from other cases where invalid actions are silently ignored,
+        # because message context is controlled by developer, and users are not able
+        # to construct update to run any specific context.
+        def action_for_message_context(context)
+          action = context.to_s
+          return action if action_method?(action)
+          raise AbstractController::ActionNotFound,
+            "The context action '#{action}' is not found in #{self.class.name}"
         end
       end
     end