Store session data in Alexa skill using python – Session Attributes in Alexa Skill Kit

Almost every Alexa skill requires a back-and-forth interaction with the user in order to make the skill more lively and interactive. In order to achieve this Amazon provides us feature called session attributes. So in this blog, I am going to talk about session attributes and give a code snippet using python.

If you are someone new to Alexa then take a look at this blog.

Using session attributes in Alexa skill development makes the fun even more enjoyable. It solves many of our technical problems and I absolutely love it.

What is a session in Alexa skills?

So whenever a user invokes your skill a session is open. In any of the responses if we return “shouldEndSession” attributes as true or if the user says “exit” then the session will close. In between this interval, we can maintain JSON data for further interaction of the skill. In order to maintain this JSON data we use session attributes.

session attributes in python

As now we have understood what is session attributes let see how to implement them.

Declaring session attributes

session_attr = handler_input.attributes_manager.session_attributes

Saving data into session attributes

session_attr['source'] = "ranjithkumarmadhavan.com"

Fetching data from session attributes

source = session_attr['source']

As simple as it looks!! This is it. Now you can maintain user data back and forth until the session is closed.

The following is a simple hello world python program.

import logging
import ask_sdk_core.utils as ask_utils

from ask_sdk_core.skill_builder import SkillBuilder
from ask_sdk_core.dispatch_components import AbstractRequestHandler
from ask_sdk_core.dispatch_components import AbstractExceptionHandler
from ask_sdk_core.handler_input import HandlerInput

from ask_sdk_model import Response

logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)


class LaunchRequestHandler(AbstractRequestHandler):
    """Handler for Skill Launch."""
    def can_handle(self, handler_input):
        # type: (HandlerInput) -> bool

        return ask_utils.is_request_type("LaunchRequest")(handler_input)

    def handle(self, handler_input):
        # type: (HandlerInput) -> Response
        session_attr = handler_input.attributes_manager.session_attributes
        speak_output = "Welcome, you can say Hello or Help. Which would you like to try?"
        session_attr['source'] = "ranjithkumarmadhavan.com"

        return (
            handler_input.response_builder
                .speak(speak_output)
                .ask(speak_output)
                .response
        )


class HelloWorldIntentHandler(AbstractRequestHandler):
    """Handler for Hello World Intent."""
    def can_handle(self, handler_input):
        # type: (HandlerInput) -> bool
        return ask_utils.is_intent_name("HelloWorldIntent")(handler_input)

    def handle(self, handler_input):
        # type: (HandlerInput) -> Response
        session_attr = handler_input.attributes_manager.session_attributes
        source = session_attr['source']
        speak_output = f"Hello World from {source}!"

        return (
            handler_input.response_builder
                .speak(speak_output)
                # .ask("add a reprompt if you want to keep the session open for the user to respond")
                .response
        )


class HelpIntentHandler(AbstractRequestHandler):
    """Handler for Help Intent."""
    def can_handle(self, handler_input):
        # type: (HandlerInput) -> bool
        return ask_utils.is_intent_name("AMAZON.HelpIntent")(handler_input)

    def handle(self, handler_input):
        # type: (HandlerInput) -> Response
        speak_output = "You can say hello to me! How can I help?"

        return (
            handler_input.response_builder
                .speak(speak_output)
                .ask(speak_output)
                .response
        )


class CancelOrStopIntentHandler(AbstractRequestHandler):
    """Single handler for Cancel and Stop Intent."""
    def can_handle(self, handler_input):
        # type: (HandlerInput) -> bool
        return (ask_utils.is_intent_name("AMAZON.CancelIntent")(handler_input) or
                ask_utils.is_intent_name("AMAZON.StopIntent")(handler_input))

    def handle(self, handler_input):
        # type: (HandlerInput) -> Response
        speak_output = "Goodbye!"

        return (
            handler_input.response_builder
                .speak(speak_output)
                .response
        )

class FallbackIntentHandler(AbstractRequestHandler):
    """Single handler for Fallback Intent."""
    def can_handle(self, handler_input):
        # type: (HandlerInput) -> bool
        return ask_utils.is_intent_name("AMAZON.FallbackIntent")(handler_input)

    def handle(self, handler_input):
        # type: (HandlerInput) -> Response
        logger.info("In FallbackIntentHandler")
        speech = "Hmm, I'm not sure. You can say Hello or Help. What would you like to do?"
        reprompt = "I didn't catch that. What can I help you with?"

        return handler_input.response_builder.speak(speech).ask(reprompt).response

class SessionEndedRequestHandler(AbstractRequestHandler):
    """Handler for Session End."""
    def can_handle(self, handler_input):
        # type: (HandlerInput) -> bool
        return ask_utils.is_request_type("SessionEndedRequest")(handler_input)

    def handle(self, handler_input):
        # type: (HandlerInput) -> Response

        # Any cleanup logic goes here.

        return handler_input.response_builder.response


class IntentReflectorHandler(AbstractRequestHandler):
    """The intent reflector is used for interaction model testing and debugging.
    It will simply repeat the intent the user said. You can create custom handlers
    for your intents by defining them above, then also adding them to the request
    handler chain below.
    """
    def can_handle(self, handler_input):
        # type: (HandlerInput) -> bool
        return ask_utils.is_request_type("IntentRequest")(handler_input)

    def handle(self, handler_input):
        # type: (HandlerInput) -> Response
        intent_name = ask_utils.get_intent_name(handler_input)
        speak_output = "You just triggered " + intent_name + "."

        return (
            handler_input.response_builder
                .speak(speak_output)
                # .ask("add a reprompt if you want to keep the session open for the user to respond")
                .response
        )


class CatchAllExceptionHandler(AbstractExceptionHandler):
    """Generic error handling to capture any syntax or routing errors. If you receive an error
    stating the request handler chain is not found, you have not implemented a handler for
    the intent being invoked or included it in the skill builder below.
    """
    def can_handle(self, handler_input, exception):
        # type: (HandlerInput, Exception) -> bool
        return True

    def handle(self, handler_input, exception):
        # type: (HandlerInput, Exception) -> Response
        logger.error(exception, exc_info=True)

        speak_output = "Sorry, I had trouble doing what you asked. Please try again."

        return (
            handler_input.response_builder
                .speak(speak_output)
                .ask(speak_output)
                .response
        )

# The SkillBuilder object acts as the entry point for your skill, routing all request and response
# payloads to the handlers above. Make sure any new handlers or interceptors you've
# defined are included below. The order matters - they're processed top to bottom.


sb = SkillBuilder()

sb.add_request_handler(LaunchRequestHandler())
sb.add_request_handler(HelloWorldIntentHandler())
sb.add_request_handler(HelpIntentHandler())
sb.add_request_handler(CancelOrStopIntentHandler())
sb.add_request_handler(FallbackIntentHandler())
sb.add_request_handler(SessionEndedRequestHandler())
sb.add_request_handler(IntentReflectorHandler()) # make sure IntentReflectorHandler is last so it doesn't override your custom intent handlers

sb.add_exception_handler(CatchAllExceptionHandler())

lambda_handler = sb.lambda_handler()

What if you want to retain the session data even after the session is closed? Don’t worry I got you covered. Take a look here.

To know more about session attributes visit the official documentation from Amazon.

Feel free to leave a comment down here. I would love to hear from you. Happy programming!!