My Lambda Code for Alexa with support for the AudioPlayer

bibletalk_alexa.js

exports.handler = function (event, context) 
{
    try 
    {
        if (event.session.application.applicationId !== "YOUR APP ID") 
        {
             context.fail("Invalid Application ID");
        }

        if (event.request.type === "LaunchRequest") 
        {
            onLaunch(event.request,
                event.session,
                function callback(sessionAttributes, speechletResponse) {
                    context.succeed(buildResponse(sessionAttributes, speechletResponse));
                });
        } 
        else if (event.request.type === "IntentRequest") 
        {
            onIntent(event.request,
                event.session,
                function callback(sessionAttributes, speechletResponse) {
                    context.succeed(buildResponse(sessionAttributes, speechletResponse));
                }, event );
        } 
        else if (event.request.type === "SessionEndedRequest") 
        {
            onSessionEnded(event.request, event.session);
            context.succeed();
        }
        else if( event.request.type.substring(0,11) === 'AudioPlayer' || event.request.type.substring(0,18) === 'PlaybackController' )
        {
            pingBTwithAlexaEvent( event.request.type, event, callback );
        }
    } 
    catch (e) 
    {
        context.fail("Exception: " + e);
    }
};


/**
 * Called when the user launches the skill without specifying what they want.
 */
function onLaunch(launchRequest, session, callback) 
{
    getWelcomeResponse(callback);
}

/**
 * Called when the user specifies an intent for this skill.
 */
function onIntent(intentRequest, session, callback, event) 
{
    var intentName  = intentRequest.intent.name;
    
    var userId = '';
    
    if( event.context ) 
    {
        userId = event.context.System.user.userId;
    } 
    else if(event.session) 
    {
        userId = event.session.user.userId;
    }
    
    if ( "AMAZON.HelpIntent" === intentName ) 
    {
        getWelcomeResponse(callback);
    } 
    else if ("AMAZON.StopIntent" === intentName || "AMAZON.CancelIntent" === intentName) 
    {
        callback({}, buildAudioStopResponse(true));
    } 
    else if ("AMAZON.PauseIntent" === intentName ) 
    {
        var offsetInMilliseconds = 0;
     
        if( event.context && event.context.AudioPlayer) 
        {
            offsetInMilliseconds = event.context.AudioPlayer.offsetInMilliseconds;
        } 
        
        pingReturn("https://bibletalk.tv/api/alexa.php?intent=AMAZON.PauseIntent&offset=" + offsetInMilliseconds + "&userId=" + userId, callback);
    }
    else if (
                "AMAZON.ResumeIntent" === intentName || 
                "AMAZON.NextIntent" === intentName || 
                "AMAZON.PreviousIntent" === intentName || 
                "AMAZON.StartOverIntent" === intentName
            ) 
    {
        pingReturn("https://bibletalk.tv/api/alexa.php?intent=" + intentName + "&userId=" + userId, callback);
    }
    else if( "AMAZON.ShuffleOnIntent" === intentName || "AMAZON.ShuffleOffIntent" === intentName )
    {
        simpleResponse("Sorry, I can’t shuffle lessons yet", callback);
    }
    else if( "AMAZON.LoopOnIntent" === intentName || "AMAZON.LoopOffIntent" === intentName )
    {
        simpleResponse("Sorry, I can’t loop lessons yet", callback);
    }
    else if( "PlayAnItemInSeries" === intentName )
    {
        pingReturn("https://bibletalk.tv/api/alexa.php?intent=" + intentName + "&series=" + intentRequest.intent.slots["Series"].value + "&number=" + intentRequest.intent.slots["Lesson"].value + "&userId=" + userId, callback);
    }
    else if( "PlayAnything" === intentName )
    {
        pingReturn("https://bibletalk.tv/api/alexa.php?intent=PlayAnything&keyword=" + intentRequest.intent.slots["Keyword"].value + "&userId=" + userId, callback);
    }
    else
    {
        pingReturn("https://bibletalk.tv/api/alexa.php?intent=" + intentName + "&userId=" + userId, callback);
    }
}


function pingReturn( url, callback )
{
    var http = require("https");
    var request = http.get(url, function (response) 
    {
        var buffer = "", data, route;
        response.on("data", function (chunk) { buffer += chunk; }); 
        response.on("end", function (err) 
        {
            callback({}, JSON.parse(buffer) );
        }); 
    });   
}


function pingBTwithAlexaEvent( eventName, event, callback )
{
    var userId = '';
    var offsetInMilliseconds = 0;
     
    if( event.context ) 
    {
        userId = event.context.System.user.userId;
        
        if( event.context.AudioPlayer )
        {
            offsetInMilliseconds = event.context.AudioPlayer.offsetInMilliseconds;
        }
    } 
    else if (event.session) 
    {
        userId = event.session.user.userId;
    }
    
    // PING BT
    var http = require("https");
    var url = "https://bibletalk.tv/api/alexa.php?event_name=" + eventName  + "&offset=" + offsetInMilliseconds + "&userId=" + userId;
    
    var request = http.get(url, function (response) 
    {
        var buffer = "", data, route;
        response.on("data", function (chunk) { buffer += chunk; }); 
        response.on("end", function (err) 
        {
            callback({}, JSON.parse(buffer) );
        }); 
    });
}


/**
 * Called when the user ends the session.
 * Is not called when the skill returns shouldEndSession=true.
 */
function onSessionEnded(sessionEndedRequest, session) 
{
    //console.log("onSessionEnded requestId=" + sessionEndedRequest.requestId + ", sessionId=" + session.sessionId);
}

// --------------- Functions that control the skill's behavior -----------------------
function simpleResponse(text, callback)
{
    callback({}, buildSpeechletResponse(text, text, text, false));
}

function getWelcomeResponse(callback) 
{
    var sessionAttributes = {};
    var cardTitle = "Welcome";
    var speechOutput = "Welcome to BibleTalk. You can ask me to play any lesson on our website. What would you like to do?";
    var repromptText = "You can ask me things like 'play the latest sermon', 'play a random devo' or even 'play lesson number four in Hebrews'. What would you like to do?";

    callback(sessionAttributes,
        buildSpeechletResponse(cardTitle, speechOutput, repromptText, false));
}

function handleSessionEndRequest(callback) {
    var cardTitle = "Session Ended";
    var speechOutput = "Thank you for using the BibleTalk.tv skill. Have a nice day.";
    callback({}, buildSpeechletResponse(cardTitle, speechOutput, null, true));
}


// --------------- Helpers that build all of the responses -----------------------

function buildSpeechletResponse(title, output, repromptText, shouldEndSession) {
    return {
        outputSpeech: {
            type: "PlainText",
            text: output
        },
        card: {
            type: "Simple",
            title: title,
            content: output
        },
        reprompt: {
            outputSpeech: {
                type: "PlainText",
                text: repromptText
            }
        },
        shouldEndSession: shouldEndSession
    };
}

function buildAudioStopResponse(shouldEndSession) 
{
    return {
        directives: [
        {
            "type": "AudioPlayer.Stop" 
        }],
        shouldEndSession: shouldEndSession
    };
}

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