Version: 3.x

rasa.core.actions.forms

FormAction Objects

class FormAction(LoopAction)

Action which implements and executes the form logic.

__init__

| __init__(form_name: Text, action_endpoint: Optional[EndpointConfig]) -> None

Creates a FormAction.

Arguments:

  • form_name - Name of the form.
  • action_endpoint - Endpoint to execute custom actions.

name

| name() -> Text

Return the form name.

required_slots

| required_slots(domain: Domain) -> List[Text]

A list of required slots that the form has to fill.

Returns:

A list of slot names.

from_entity

| from_entity(entity: Text, intent: Optional[Union[Text, List[Text]]] = None, not_intent: Optional[Union[Text, List[Text]]] = None, role: Optional[Text] = None, group: Optional[Text] = None) -> Dict[Text, Any]

A dictionary for slot mapping to extract slot value.

From:

  • an extracted entity
  • conditioned on
    • intent if it is not None
    • not_intent if it is not None, meaning user intent should not be this intent
    • role if it is not None
    • group if it is not None

get_mappings_for_slot

| get_mappings_for_slot(slot_to_fill: Text, domain: Domain) -> List[Dict[Text, Any]]

Get mappings for requested slot.

If None, map requested slot to an entity with the same name

entity_mapping_is_unique

| entity_mapping_is_unique(slot_mapping: Dict[Text, Any], domain: Domain) -> bool

Verifies if the from_entity mapping is unique.

get_entity_value_for_slot

| @staticmethod
| get_entity_value_for_slot(name: Text, tracker: "DialogueStateTracker", slot_to_be_filled: Text, role: Optional[Text] = None, group: Optional[Text] = None) -> Any

Extract entities for given name and optional role and group.

Arguments:

  • name - entity type (name) of interest
  • tracker - the tracker
  • slot_to_be_filled - Slot which is supposed to be filled by this entity.
  • role - optional entity role of interest
  • group - optional entity group of interest

Returns:

Value of entity.

get_slot_to_fill

| get_slot_to_fill(tracker: "DialogueStateTracker") -> Optional[str]

Gets the name of the slot which should be filled next.

When switching to another form, the requested slot setting is still from the previous form and must be ignored.

Returns:

The slot name or None

validate_slots

| async validate_slots(slot_candidates: Dict[Text, Any], tracker: "DialogueStateTracker", domain: Domain, output_channel: OutputChannel, nlg: NaturalLanguageGenerator) -> List[Union[SlotSet, Event]]

Validate the extracted slots.

If a custom action is available for validating the slots, we call it to validate them. Otherwise there is no validation.

Arguments:

  • slot_candidates - Extracted slots which are candidates to fill the slots required by the form.
  • tracker - The current conversation tracker.
  • domain - The current model domain.
  • output_channel - The output channel which can be used to send messages to the user.
  • nlg - NaturalLanguageGenerator to use for response generation.

Returns:

The validation events including potential bot messages and SlotSet events for the validated slots, if the custom form validation action is present in domain actions. Otherwise, returns empty list since the extracted slots already have corresponding SlotSet events in the tracker.

validate

| async validate(tracker: "DialogueStateTracker", domain: Domain, output_channel: OutputChannel, nlg: NaturalLanguageGenerator) -> List[Union[SlotSet, Event]]

Extract and validate value of requested slot and other slots.

Returns:

The new validation events created by the custom form validation action

Raises:

ActionExecutionRejection exception to reject execution of form action if nothing was extracted.

Subclass this method to add custom validation and rejection logic.

request_next_slot

| async request_next_slot(tracker: "DialogueStateTracker", domain: Domain, output_channel: OutputChannel, nlg: NaturalLanguageGenerator, events_so_far: List[Event]) -> List[Union[SlotSet, Event]]

Request the next slot and response if needed, else return None.

activate

| async activate(output_channel: "OutputChannel", nlg: "NaturalLanguageGenerator", tracker: "DialogueStateTracker", domain: "Domain") -> List[Event]

Activate form if the form is called for the first time.

If activating, validate any required slots that were filled before form activation and return Form event with the name of the form, as well as any SlotSet events from validation of pre-filled slots.

Arguments:

  • output_channel - The output channel which can be used to send messages to the user.
  • nlg - NaturalLanguageGenerator to use for response generation.
  • tracker - Current conversation tracker of the user.
  • domain - Current model domain.

Returns:

Events from the activation.

is_done

| async is_done(output_channel: "OutputChannel", nlg: "NaturalLanguageGenerator", tracker: "DialogueStateTracker", domain: "Domain", events_so_far: List[Event]) -> bool

Checks if loop can be terminated.

deactivate

| async deactivate(*args: Any, **kwargs: Any) -> List[Event]

Deactivates form.