Intent with required parameter showing the count of items - dialogflow-es

Question

trying to make an Intent for my first Conversational Assistant with a couple of parameters. Everything is build in Dialogflow and for some of my functionality I use fulfillment.
The easiest way to describe my assistant is as a cinema tickets booking.
I need to store #number_of_tickets, #cinema, #movie. The last two (#cinema and #movie) are very easy to solve with entities, however struggle a lot with #number_of_tickets. All of this parameters should be mandatory.
My goal is to allow such kind of functionality:
Book me a ticket for Star Wars in IMax (ticket = 1 = #number_of_tickets, Star Wars = #movie, IMax = #cinema)
Book me 2 tickets for Star Wars in IMax(2 tickets = 2 = #number_of_tickets, Star Wars = #movie, IMax = #cinema)
Book me tickets for Star Wars in IMax -> How many tickets you want to book?
I tried with composite Entities but it doesn't work as I'm expecting.
How I can enable such kind of functionality in Dialogflow?
Is there a way to require #number_of_tickets to be between 1 and 5?

Answer 1

Above question can be achieved by following below steps:
Solution:
Step 1:
Create Entities for movie and cinema:
Cinema:
Movie:
Step 2:
Create an intent with three parameters:
(If you want alow only from 1 to 5 then you can create an entity like cinema and movies with entries from 1 to 5 and map the number of tickets parameter with the same)
Step 3:
Make all the parameter Mandatory and define prompts for all as below:
Movie Prompts:
Cinema Prompts:
Number of tickets prompts:
Result:

Answer 2

It may not be obvious, but the answer to both of your questions can be addressed by remembering that Intents capture what the user says, and not what you do with what they say. You can have multiple Intents to capture different phrases, and handle them in mostly the same way in your fulfillment. (And these do require that you have some kind of fulfillment webhook behind the scenes.)
How can I assume a default of 1 ticket?
There are a couple of approaches.
The first is that you can setup an Intent to capture phrases that suggest a single ticket and a different Intent that explicitly requires a number. So perhaps one Intent (possibly book.single) with
I'd like to get a ticket for Star Wars in IMax
How about the IMax showing for Star Wars
Let me see the Star Wars for IMax
and so forth. While you'd also have a different Intent (possibly book.multiple) with
I'd like 2 tickets for Star Wars in IMax
2 tickets please for the IMax Star Wars
etc.
In your fulfillment, you might have some function that takes three parameters
bookTickets( num, movie, cinema );
In your Intent handler for book.single, you'd call this with
bookTickets( 1, movieParameter, cinemaParameter );
while in the Intent handler for book.multiple, this would be done with
bookTickets( countParameter, movieParameter, cinemaParameter );
In each case, the fulfillment still ends up calling the same function to do the actual work, but the handler sets the values as appropriate.
How can I limit how many tickets get ordered?
This goes to something that you didn't address - what do you want to happen if they try to order more? Do you want to direct them to a group order conversation? Reject it outright? Whatever you want - make sure you've planned out this path of a conversation before you try to implement it.
In this case, this isn't something you want to enforce in the Dialogflow Intent. Handling it in your fulfillment is easiest. There, you would apply any logic for the various parameters and return a message, prompting them about their next reply.
Logic is best handled in the fulfillment.
There are actually a couple of places this is important in your example. In the first, how would you handle more than 5 tickets requested? In your handler for book.multiple, you would check how many are requested. If between 1 and 5 inclusive, you'd call the book function above. But if not, you might want to just send back a replying saying "I'm sorry, you can only reserve 5 tickets maximum. How many tickets do you want?"
You would also need a new Intent to capture the reply. It could be as simple as just taking a number, but to make sure it only gets applied when you send back this prompt, you may want to set an Output Context indicating you're prompting for the number of tickets and then set this as an Input Context for the Intent that collects a number.
Are there other cases where you might want to apply logic before booking tickets? Plenty - and in each case you will probably want to make sure there is a new Intent that can capture what they want. For example, what if the movie they want to book isn't showing in that cinema? What if you already know that movie is sold out?
But what about Followup Intents?
Followup Intents are generally best avoided in general for exactly the same reason - Intents represent what the user says, and shouldn't try to model your code logic. There is nothing special about a Followup Intent - you can create an Intent at the top level that works the same way, but will be valid only if you prompt for certain things. How? Contexts again!
So if you prompt with possible showtimes ("Do you want the 2:00, 4:00, or 6:00 show?") you could also include a context (say "promptTime", for example) and then have an Intent that expects this as an Input Context and matches the times.
Conclusion
Intents represent what the user says
Your fulfillment code does something with what they've said
You can prompt them for more or different information in your fulfillment
Contexts can shape what replies you expect
Multiple Intent Handlers can call the same functions to do the work