main.py

import boto3
import json
import urllib
import urllib2

def lambda_handler(event, context):

    if event['session']['application']['applicationId'] != "amzn1.echo-sdk-ams.app.<your-alexa-skills-id>":
        print "Invalid Application ID"
    else:
        sessionAttributes = {}

        if event['session']['new']:
            onSessionStarted(event['request']['requestId'], event['session'])
        if event['request']['type'] == "LaunchRequest":
            speechlet = onLaunch(event['request'], event['session'])
            response = buildResponse(sessionAttributes, speechlet)
        elif event['request']['type'] == "IntentRequest":
            speechlet = onIntent(event['request'], event['session'])
            response = buildResponse(sessionAttributes, speechlet)
        elif event['request']['type'] == "SessionEndedRequest":
            speechlet = onSessionEnded(event['request'], event['session'])
            response = buildResponse(sessionAttributes, speechlet)

        # Return a response for speech output
        return(response)

# Called when the session starts
def onSessionStarted(requestId, session):
    print("onSessionStarted requestId=" + requestId + ", sessionId=" + session['sessionId'])

# Called when the user launches the skill without specifying what they want.
def onLaunch(launchRequest, session):
    # Dispatch to your skill's launch.
    getWelcomeResponse()

# Called when the user specifies an intent for this skill.
def onIntent(intentRequest, session):
    intent = intentRequest['intent']
    intentName = intentRequest['intent']['name']

    # Dispatch to your skill's intent handlers
    if intentName == "BrewIntent":
        return brewIntent(intent)
    elif intentName == "HelpIntent":
        return getWelcomeResponse()
    else:
        print "Invalid Intent (" + intentName + ")"
        raise

# Called when the user ends the session.
# Is not called when the skill returns shouldEndSession=true.
def onSessionEnded(sessionEndedRequest, session):
    # Add cleanup logic here
    print "Session ended"

def brewIntent(intent):
    repromptText = "You can say brew me a cup of coffee"
    shouldEndSession = True

    speechOutput = "Ok, I'm brewing your coffee"
    cardTitle = speechOutput

    # Make a call to AWS IoT to update the shadow. The Raspberry Pi
    # connected to the Keurig watches the shadow topic for instructions
    # to start the brew
    client = boto3.client('iot-data')
    response = client.update_thing_shadow(
        thingName='coffee',
        payload=b'{"state" : { "desired" : { "brew" : "start" }}}'
    )

    repromptText = "I didn't understand that."
    shouldEndSession = True

    return(buildSpeechletResponse(cardTitle, speechOutput, repromptText, shouldEndSession))


def getWelcomeResponse():
    sessionAttributes = {}
    cardTitle = "Welcome"
    speechOutput = """You can ask me to brew you a cup of coffee by saying brew me a cup of coffee"""

    # If the user either does not reply to the welcome message or says something that is not
    # understood, they will be prompted again with this text.
    repromptText = speechOutput
    shouldEndSession = True

    return (buildSpeechletResponse(cardTitle, speechOutput, repromptText, shouldEndSession))

# --------------- Helpers that build all of the responses -----------------------
def buildSpeechletResponse(title, output, repromptText, shouldEndSession):
    return ({
        "outputSpeech": {
            "type": "PlainText",
            "text": output
        },
        "card": {
            "type": "Simple",
            "title": "SessionSpeechlet - " + title,
            "content": "SessionSpeechlet - " + output
        },
        "reprompt": {
            "outputSpeech": {
                "type": "PlainText",
                "text": repromptText
            }
        },
        "shouldEndSession": shouldEndSession
    })

def buildResponse(sessionAttributes, speechletResponse):
    return ({
        "version": "1.0",
        "sessionAttributes": sessionAttributes,
        "response": speechletResponse
    })