alexa-app-with-promises.js

app.launch(function(request, response) {
    return Promise.resolve().then(() => {
        const accessTokenReceived = request.sessionDetails.accessToken;
        if (accessTokenReceived === undefined) {
            throw 'no_access_token';
        }

        return user.getUserFromAccessTokenPromise(accessTokenReceived);
    }).catch(() => {
        throw 'not_good_access_token';
    }).then(user => stuff.getStuffFromUserPromise(user).then(stuff => ({stuff, user, userId: user.id})))
    .catch(() => {
        throw 'no_stuff';
    }).then(({userId}) => helper.getStaffUserIdPromise(userId))
    .catch(() => {
        throw 'error_retrieving_staff';
    }).then(() => {
        if (numberOfStaff !== 0) {
            return response.say(config.dialog.onLaunchIntent.case13.say)
                    .reprompt(config.dialog.onLaunchIntent.case13.reprompt)
                    .card(config.dialog.onLaunchIntent.case13.cardTitle, config.dialog.onLaunchIntent.case12.card)
                    .shouldEndSession(config.dialog.onLaunchIntent.case13.end);
        }
        throw "no_staff";
    })
    .catch(err => {
        switch (err) {
            case "no_access_token":
                response.say(config.dialog.onLaunchIntent.case10.say)
                    .reprompt(config.dialog.onLaunchIntent.case10.reprompt)
                    .linkAccount()
                    .shouldEndSession(config.dialog.onLaunchIntent.end);
                break;
            case "not_good_access_token":
                response.say(config.dialog.onLaunchIntent.case10.say)
                    .reprompt(config.dialog.onLaunchIntent.case10.reprompt)
                    .linkAccount()
                    .shouldEndSession(config.dialog.onLaunchIntent.case10.end);
                break;
            case "no_stuff":
                response.say(config.dialog.onLaunchIntent.case11.say)
                    .reprompt(config.dialog.onLaunchIntent.case11.reprompt)
                    .card(config.dialog.onLaunchIntent.case11.cardTitle, config.dialog.onLaunchIntent.case11.card)
                    .shouldEndSession(config.dialog.onLaunchIntent.case11.end);
                break;
            case "no_staff":
                response.say(config.dialog.onLaunchIntent.case12.say)
                    .reprompt(config.dialog.onLaunchIntent.case12.reprompt)
                    .card(config.dialog.onLaunchIntent.case12.cardTitle, config.dialog.onLaunchIntent.case12.card)
                    .shouldEndSession(config.dialog.onLaunchIntent.case12.end);
                break;
            default:
                response.say(config.dialog.onLaunchIntent.case6.say)
                    .reprompt(config.dialog.onLaunchIntent.case6.reprompt)
                    .card(config.dialog.onLaunchIntent.case6.cardTitle, config.dialog.onLaunchIntent.case6.card)
                    .shouldEndSession(config.dialog.onLaunchIntent.case6.end);
        }
    });
});