Conditionals

Conditional statements allow you to specify when a particular content item or forwarding or redirecting path will be selected.

Example usages:

You want to provide a specific response a particular slot is not provided to then prompt for the slot value
You want to provide a specific welcome message, by using a segment, depending on when the user was last seen
You want redirect a user to another handler depending on if they have linked their account or not.

The following is a list of popular functions that are available. All of these return either true or false, some take parameters and some do not. You can use these functions to create a conditional strings.

They can be simple, such as a conditional if the user has been active within the last two months

activeWithin(2, "months")

or not active within two months, notice the leading exclamation point to negate the boolean the function returns:

!activeWithin(2, "months")

They can also be more complex, this is for a user that is starting a session and has not linked their account yet:

isNewSession() && !hasLinkedAccount()

The following is a list of popular functions that are available.

Active Within

The user has been active within the provided amount. This can be used to provide a response to a user that has used the application before but are coming back after some time and need a refresher.

activeWithin(amount: number, format: DurationFormat)

For example, the user is active within the last five days.

activeWithin(5, "days")

The available formats are "years", "quarters", "months", "weeks", "days", "hours", "minutes", "seconds", "milliseconds".

Fits Schedule

The current time for the user fits within the provided schedule.

fitsSchedule(start: string, startFormat: string, durationAmount: number, durationFormat: string, timeZone?: string)

For example, for a schedule that starts on September 11, 2019 at midnight and runs for five days.

fitsSchedule("2019-09-11T00:00", "YYYY-MM-DDTmm:ss", 5, "days")

Is Request Type

The following are available to check the type of request:

isIntentRequest()

isLaunchRequest()

isInputUnknownRequest()

Note: These do not have parameters.

Request IDs

To match based on the ID of the request:

isRequestID(id: string | string[])

You can either provide a single string or an array of strings.

isRequestID("LaunchRequest")

isRequestID(["FooIntent", "BarIntent"])

which will return true for either of the two IDs provided.

Slot Exists

You can check if a slot exists:

hasSlot(name: string)

slotExists(name: string)

Where name is the name of the slot and both will return true if the slot exists and does not equal an empty string.

Slot Equals

You can check for a slot's value:

slotEquals(name: string, value: string)

For example, you are expecting slot named "university" to equal "University of Virginia"

slotEquals("university", "University of Virginia")

Common Patterns

Slot filling

If you have a required slot, you can designate a response with the following conditional:

slotDoesNotExist("required_slot_name")

The response will then ask specifically for the missing slot value.

Required condition and one of two possibilities

You may need to set one required condition with two other possibilities. All logical JavaScript operators are supported so the pattern is:

REQUIRED && (OPTION_1 || OPTION_2)

To then translate this to an actual use case, you have scheduled content that can be accessed through two possible slot values, like a sporting event.

fitsSchedule("2019-09-11T18:40", "YYYY-MM-DDTmm:ss", 210, "minutes") && ( slotEquals("team", "one") || slotEquals("team", "two")

Note

This is not an exhaustive list of functions, more can be found by reading the source code.

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