Unable to pass control to another method within a dialog in botbuilder for Node.js - node.js

Question

I'm creating my first bot with Node.js and MS Bot Framework and I'm trying to figure out how to pass control from one method to another within a dialog.
In Bot Framework for C#, it's very easy:
context.Wait(NextMethodName);
where NextMethodName is the name of the method that runs after the bot receives the next user message.
I am trying to do a similar thing in Node.js. I have two functions. The first one prompts the user to enter something or click a button, and the second should process the user's input. I am struggling with passing control to the second function.
bot.dialog('subscribe', [
function (session) {
var card = new builder.HeroCard(session)
.title("Subscribe for reminders?")
.text("It seems you're not enrolled yet. Subscribe for reminders to submit your work hours?")
.buttons([
builder.CardAction.imBack(session, "subscribe", "Subscribe")
]);
var msg = new builder.Message(session).attachments([card]);
session.send(msg);
//next(); //compile error
},
function (session, results) {
if (results.response === 'subscribe') {
session.send('You are now subscribed to reminders through ' + session.message.user.channelId + '.');
}
else {
session.send('You must subscribe to reminders before using this bot.');
}
}
]);
How do I make the second function run after the user clicks the button or answers anything?

Answer 1

In node's botbuilder sdk, you can define waterfall dialogs that contains what are called as 'steps'. Each step leads to another (like a waterfall). According to docs:
'Waterfalls let you collect input from a user using a sequence of steps. A bot is
always in a state of providing a user with information or asking a
question and then waiting for input. In the Node version of Bot
Builder it's waterfalls that drive this back-n-forth flow'.
Some steps can start with a prompt to ask the user for information, and then the following step handles the response by saving it using dialogData. Then you can invoke the next function argument to pass control to the next step. In your case, calling next() gives you an error because that function isn't in scope, you must provide it as a parameter to your step function.
Check this sample here:
https://github.com/Microsoft/BotBuilder-Samples/tree/master/Node/core-MultiDialogs
In your first step code I would do:
function (session,args,next) {
var card = new builder.HeroCard(session)
.title("Subscribe for reminders?")
.text("It seems you're not enrolled yet. Subscribe for reminders to submit your work hours?")
.buttons([
builder.CardAction.imBack(session, "subscribe", "Subscribe")
]);
var msg = new builder.Message(session).attachments([card]);
session.send(msg);
next();
}
But that would just lead you to the next step, so if you want to wait for user input (with text prompt), or for example using HeroCard actions, like you defined in your sample:
Your card triggers an action called "subscribe" with the parameter "Subscribe" via a button. Think of this as a function that is called within your dialog by pressing the button on the card. Now to define that function, we do:
// An action is essentially a card calling a global dialog method
// with respective parameters. This dialog action will route the action
// command to a dialog.
bot.beginDialogAction('subscribe', '/subscribe');
// Create the dialog for the action...
bot.dialog('/subscribe', [
function (session, args) {
//do something!
}
]);