Introduction to Forms

In this segment we will teach you how to configure Rasa Forms. Having a form has many benefits, but the main one is that it allows us to add constraints to how we collect slot values.

Video


Code

There are some important changes that we've made to our domain.yml file.

entities:
- shirt_size


slots:
  shirt_size:
    type: text
    influence_conversation: true
    mappings:
    - type: from_entity
      entity: shirt_size
      conditions:
      - active_loop: shirt_size_form


forms:
  shirt_size_form:
    required_slots:
    - shirt_size

The main thing we've added now is the conditions in the slot mappings. This ensures that we only store the slot information if the user is in an active form.

Rules

In order to make the form work, we need to add some rules to our rules.yml file.

rules:
- rule: Activate form
  steps:
  - intent: ask_me_anything
  - action: shirt_size_form
  - active_loop: shirt_size_form


- rule: Submit form
  condition:
  - active_loop: shirt_size_form
  steps:
  - action: shirt_size_form
  - active_loop: null
  - slot_was_set:
    - requested_slot: null
  - action: utter_remember

Stories

Again, we also ensure that we have stories available. Here's an example that's been extracted from a long rasa interactive conversation.

- story: interactive story
  steps:
  - intent: greet
  - action: utter_greet
  - intent: mood_unhappy
  - action: utter_cheer_up
  - action: utter_did_that_help
  - intent: affirm
  - action: utter_happy
  - intent: repeat_shirt_size
  - action: action_say_shirt_size
  - intent: ask_me_anything
  - action: shirt_size_form
  - active_loop: shirt_size_form
  - slot_was_set:
    - requested_slot: shirt_size
  - slot_was_set:
    - shirt_size: large
  - slot_was_set:
    - requested_slot: null
  - active_loop: null
  - action: utter_remember
  - intent: repeat_shirt_size
  - action: action_say_shirt_size
  - intent: mood_unhappy
  - action: utter_cheer_up
  - action: utter_did_that_help
  - intent: affirm
  - action: utter_happy

Links

Exercises

Try to answer the following questions to test your knowledge.

  1. Why do we prefer to use conditions in our forms?
  2. Can you think of a situation where you don't want to use conditions?
  3. What will happen if the form cannot fill in a slot value?
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