验证槽值¶
本指南介绍了验证流中 collect 步骤后返回的槽值的不同方法。简单的验证可以在流步骤本身中定义，而需要外部数据的验证则由自定义动作执行。
验证电话号码¶
假设对话机器人有一个流，允许用户更改与其帐户关联的电话号码。请注意，collect 步骤的 description 字段已经向命令生成器提供了有关所需格式的信息。
flows:
update_number:
description: allows users to update the phone
number associated with their account.
steps:
- collect: phone_number
description: 'an entire US phone number,
including the area code.
For example: (415) 555-1234 .
When setting as a slot use this format,
with brackets and a hyphen,
even if the user didnt type it that way.'
slots:
phone_number:
type: text
responses:
utter_ask_phone_number:
- text: "What is the new phone number?"
使用条件验证槽值的格式¶
拒绝是一种对提取的槽值进行简单验证的轻量级方法。在 collect 步骤中添加 rejections 字段，以验证 LLMCommandGenerator 提取的电话号码，并在其不匹配时拒绝该值。此示例使用正则表达式，你可以使用任何条件。
flows:
update_number:
description: allows users to update the phone
number associated with their account.
steps:
- collect: phone_number
description: 'an entire US phone number,
including the area code.
For example: (415) 555-1234 .
When setting as a slot use this format,
with brackets and a hyphen,
even if the user didnt type it that way.'
rejections:
- if: not ( slots.phone_number matches "^\([0-9]{3}\) [0-9]{3}-[0-9]{4}$")
utter: utter_invalid_phone_number
记得在领域中添加相应的 response，以通知用户其电话号码未成功收集。之后将再次要求用户输入其电话号码。
responses:
...
utter_invalid_phone_number:
- text: "Sorry, I didn't get that. Please use the format (xxx) xxx-xxxx"
根据数据库或 API 验证槽值¶
如果你需要更高级的逻辑来决定是否接受槽值，则可以使用自定义动作而不是拒绝。例如，如果你需要外部数据来了解槽值是否有效，则可以使用自定义动作。此示例检查是否已有另一个帐户与此电话号码关联。
为此，请将 action 步骤添加到流中，并使用以下条件来处理分支逻辑。首先，创建一个自定义动作来调用 API：
from typing import Any, Text, Dict, List
from rasa_sdk import Action, Tracker
from rasa_sdk.events import SlotSet
from rasa_sdk.executor import CollectingDispatcher
class ActionCheckPhoneNumberHasAccount(Action):
def name(self) -> Text:
return "action_check_phone_number_has_account"
def run(self, dispatcher: CollectingDispatcher,
tracker: Tracker,
domain: Dict[Text, Any]) -> List[Dict[Text, Any]]:
new_number = tracker.get_slot("phone_number")
# Mock logic for deciding if a number is available.
# This is where you would call an API.
has_account = hash(new_number) % 2 == 0
return [SlotSet("phone_number_has_account", has_account)]
此示例动作使用号码的哈希值来确定结果，以便你可以使用固定物编写确定性的端到端测试。
并将一个名为 phone_number_has_account 的布尔槽添加到领域中，以及在电话号码已与另一个帐户关联的情况下发送的响应。将自定义动作的名称添加到领域中：
slots:
...
phone_number_has_account:
type: bool
actions:
- action_check_phone_number_has_account
responses:
...
utter_inform_phone_number_has_account:
- text: "Unfortunately that number is already associated with an account."
现在，向流添加一个新步骤来调用此自定义动作。在此步骤的 next 字段中创建一个条件，以根据 phone_number_has_account 槽进行分支。如果该号码已经有帐户，对话机器人将通知用户，取消设置 phone_number 槽，并返回到表单的开头。为了跳回到表单的开头，请在流的第一步中添加一个“id”字段。流现在应该如下所示：
flows:
update_number:
description: allows users to update the phone
number associated with their account.
steps:
- id: "collect_phone_number"
collect: phone_number
description: 'an entire US phone number,
including the area code.
For example: (415) 555-1234 .
When setting as a slot use this format,
with brackets and a hyphen,
even if the user didnt type it that way.'
rejections:
- if: not ( slots.phone_number matches "^\([0-9]{3}\) [0-9]{3}-[0-9]{4}$")
utter: utter_invalid_phone_number
- action: action_check_phone_number_has_account
next:
- if: slots.phone_number_has_account
then:
- action: utter_inform_phone_number_has_account
- set_slots:
- phone_number: null
next: "collect_phone_number"