nextwork-banker-bot.yaml

---
AWSTemplateFormatVersion: 2010-09-09
Transform: AWS::Serverless-2016-10-31

Description: |-
  Sample Lex V2 Banker Bot using CloudFormation Custom Resource

Parameters:
  SarAppArn:
    Description: >-
      ARN of SAR Lex CloudFormation Custom Resource application
    Type: String
    Default: arn:aws:serverlessrepo:us-east-1:777566285978:applications/lex-v2-cfn-cr
  SarAppVersion:
    Description: >-
      Semantic version of SAR Lex CloudFormation Custom Resource application
    Type: String
    Default: 0.3.0

Globals:
  Function:
    Runtime: python3.12

Resources:
  # this deploys the Custom Resource as a nested CloudFormation stack
  LexV2CfnCr:
    Type: AWS::Serverless::Application
    Properties:
      Location:
        ApplicationId: !Ref SarAppArn
        SemanticVersion: !Ref SarAppVersion
      Parameters:
        # Custom Resource Lambda log level
        LogLevel: DEBUG

  LexBot:
    Type: Custom::LexBot
    Properties:
      ServiceToken: !GetAtt LexV2CfnCr.Outputs.LexV2CfnCrFunctionArn
      botName: !Sub "${AWS::StackName}-BankerBot"
      dataPrivacy:
        childDirected: False
      description: Example Banker bot to demonstrate Lex V2 capabilities
      idleSessionTTLInSeconds: 300
      roleArn: !GetAtt LexV2CfnCr.Outputs.LexServiceLinkedRole
      CR.botLocales:
        - localeId: en_US
          nluIntentConfidenceThreshold: 0.40
          voiceSettings:
            voiceId: Ivy
          CR.slotTypes:
            - slotTypeName: accountType
              valueSelectionSetting:
                resolutionStrategy: TopResolution
              slotTypeValues:
                - sampleValue:
                    value: Checking
                - sampleValue:
                    value: Savings
                - sampleValue:
                    value: Credit
                  synonyms:
                    - value: credit card
                    - value: visa
                    - value: mastercard
                    - value: amex
                    - value: american express
          CR.intents:
            - intentName: FallbackIntent
              description: Default fallback intent when no other intent matches
              intentClosingSetting:
                closingResponse:
                  messageGroups:
                    - message:
                        plainTextMessage:
                          value: >-
                            Sorry I am having trouble understanding.
                            Can you describe what you'd like to do in a few
                            words? I can help you find your account balance,
                            transfer funds and make a payment.
            - intentName: Welcome
              description: Welcome intent
              sampleUtterances:
                - utterance: Hi
                - utterance: Hello
                - utterance: I need help
                - utterance: Can you help me?
              intentClosingSetting:
                closingResponse:
                  messageGroups:
                    - message:
                        plainTextMessage:
                          value: >-
                            Hi! I'm BB, the Banking Bot. How can I help you
                            today?
            - intentName: CheckBalance
              description:
                Intent to check the balance in the specified account type
              sampleUtterances:
                - utterance: What’s the balance in my account ?
                - utterance: Check my account balance
                - utterance: What’s the balance in my {accountType} account ?
                - utterance: How much do I have in {accountType} ?
                - utterance: I want to check the balance
                - utterance: Can you help me with account balance ?
                - utterance: Balance in {accountType}
              fulfillmentCodeHook:
                enabled: True
              outputContexts:
                - name: contextCheckBalance
                  timeToLiveInSeconds: 90
                  turnsToLive: 5
              CR.slots:
                - slotName: accountType
                  CR.slotTypeName: accountType
                  valueElicitationSetting:
                    slotConstraint: Required
                    promptSpecification:
                      messageGroups:
                        - message:
                            plainTextMessage:
                              value:
                                For which account would you like your balance?
                      maxRetries: 2
                - slotName: dateOfBirth
                  CR.slotTypeName: AMAZON.Date
                  valueElicitationSetting:
                    slotConstraint: Required
                    promptSpecification:
                      messageGroups:
                        - message:
                            plainTextMessage:
                              value: >-
                                For verification purposes, what is your date of
                                birth?
                      maxRetries: 2
            - intentName: FollowupCheckBalance
              description: >-
                Intent to allow a follow-up balance check request without
                authentication
              sampleUtterances:
                - utterance: How about my {accountType} account
                - utterance: What about {accountType}
                - utterance: And in {accountType} ?
              fulfillmentCodeHook:
                enabled: True
              inputContexts:
                - name: contextCheckBalance
              CR.slots:
                - slotName: accountType
                  CR.slotTypeName: accountType
                  valueElicitationSetting:
                    slotConstraint: Required
                    promptSpecification:
                      messageGroups:
                        - message:
                            plainTextMessage:
                              value:
                                For which account would you like your balance?
                      maxRetries: 2
                - slotName: dateOfBirth
                  CR.slotTypeName: AMAZON.Date
                  valueElicitationSetting:
                    slotConstraint: Required
                    promptSpecification:
                      messageGroups:
                        - message:
                            plainTextMessage:
                              value: >-
                                For verification purposes, what is your date of
                                birth?
                      maxRetries: 2
                    defaultValueSpecification:
                      defaultValueList:
                        - defaultValue: '#contextCheckBalance.dateOfBirth'
            - intentName: TransferFunds
              description: Help user transfer funds between bank accounts
              sampleUtterances:
                - utterance: I want to transfer funds
                - utterance: Can I make a transfer?
                - utterance: I want to make a transfer
                - utterance: >-
                    I'd like to transfer {transferAmount} from
                    {sourceAccountType} to {targetAccountType}
                - utterance: >-
                    Can I transfer {transferAmount} to my {targetAccountType}
                - utterance: Would you be able to help me with a transfer?
                - utterance: Need to make a transfer
              fulfillmentCodeHook:
                enabled: False
              intentConfirmationSetting:
                declinationResponse:
                  messageGroups:
                    - message:
                        plainTextMessage:
                          value: The transfer has been cancelled
                promptSpecification:
                  messageGroups:
                    - message:
                        plainTextMessage:
                          value: >-
                            Got it. So we are transferring {transferAmount} from
                            {sourceAccountType} to {targetAccountType}.
                            Can I go ahead with the transfer?
                  maxRetries: 2
              intentClosingSetting:
                closingResponse:
                  messageGroups:
                    - message:
                        plainTextMessage:
                          value: >-
                            The transfer is complete. {transferAmount} should
                            now be available in your {targetAccountType}
                            account.
              CR.slots:
                - slotName: sourceAccountType
                  CR.slotTypeName: accountType
                  valueElicitationSetting:
                    slotConstraint: Required
                    promptSpecification:
                      messageGroups:
                        - message:
                            plainTextMessage:
                              value:
                                Which account would you like to transfer from?
                      maxRetries: 2
                - slotName: targetAccountType
                  CR.slotTypeName: accountType
                  valueElicitationSetting:
                    slotConstraint: Required
                    promptSpecification:
                      messageGroups:
                        - message:
                            plainTextMessage:
                              value: Which account are you transferring to?
                      maxRetries: 2
                - slotName: transferAmount
                  CR.slotTypeName: AMAZON.Number
                  valueElicitationSetting:
                    slotConstraint: Required
                    promptSpecification:
                      messageGroups:
                        - message:
                            plainTextMessage:
                              value: How much money would you like to transfer?
                      maxRetries: 2

  LexBotVersion:
    # Bot versions are deleted by the Bot on Stack Deletions
    DeletionPolicy: Retain
    # Version number changes between updates which cause a CloudFormation
    # delete event since the version number is the physical resource ID.
    # The following policies prevents deletion events
    UpdateReplacePolicy: Retain
    Type: Custom::LexBotVersion
    Properties:
      ServiceToken: !GetAtt LexV2CfnCr.Outputs.LexV2CfnCrFunctionArn
      botId: !Ref LexBot
      # botVersionLocaleSpecification is derived from the bot locales
      CR.botLocaleIds: !GetAtt LexBot.botLocaleIds
      CR.lastUpdatedDateTime: !GetAtt LexBot.lastUpdatedDateTime

  LexBotAlias:
    # Alias is deleted by the Bot on Stack Deletions
    DeletionPolicy: Retain
    Type: Custom::LexBotAlias
    Properties:
      ServiceToken: !GetAtt LexV2CfnCr.Outputs.LexV2CfnCrFunctionArn
      botId: !Ref LexBot
      botAliasName: live
      botVersion: !Ref LexBotVersion
      botAliasLocaleSettings:
        en_US:
          enabled: True
          # Lambda Code Hook
          codeHookSpecification:
            lambdaCodeHook:
              lambdaARN: !GetAtt LexBotFunction.Arn
              codeHookInterfaceVersion: "1.0"

  LexBotFunction:
    Type: AWS::Serverless::Function
    Properties:
      Description:
        !Sub "Lex Fulfillment Function for bot: ${AWS::StackName}-BankerBot"
      Handler: lambda_function.lambda_handler
      MemorySize: 128
      Timeout: 3
      InlineCode: |-
        import random
        import decimal

        def random_num():
            return(decimal.Decimal(random.randrange(1000, 50000))/100)

        def get_slots(intent_request):
            return intent_request['sessionState']['intent']['slots']

        def get_slot(intent_request, slotName):
            slots = get_slots(intent_request)
            if slots is not None and slotName in slots and slots[slotName] is not None:
                return slots[slotName]['value']['interpretedValue']
            else:
                return None

        def get_session_attributes(intent_request):
            sessionState = intent_request['sessionState']
            if 'sessionAttributes' in sessionState:
                return sessionState['sessionAttributes']

            return {}

        def elicit_intent(intent_request, session_attributes, message):
            return {
                'sessionState': {
                    'dialogAction': {
                        'type': 'ElicitIntent'
                    },
                    'sessionAttributes': session_attributes
                },
                'messages': [ message ] if message != None else None,
                'requestAttributes': intent_request['requestAttributes'] if 'requestAttributes' in intent_request else None
            }

        def close(intent_request, session_attributes, fulfillment_state, message):
            intent_request['sessionState']['intent']['state'] = fulfillment_state
            return {
                'sessionState': {
                    'sessionAttributes': session_attributes,
                    'dialogAction': {
                        'type': 'Close'
                    },
                    'intent': intent_request['sessionState']['intent']
                },
                'messages': [message],
                'sessionId': intent_request['sessionId'],
                'requestAttributes': intent_request['requestAttributes'] if 'requestAttributes' in intent_request else None
            }

        def CheckBalance(intent_request):
            session_attributes = get_session_attributes(intent_request)
            slots = get_slots(intent_request)
            account = get_slot(intent_request, 'accountType')
            #The account balance in this case is a random number
            #Here is where you could query a system to get this information
            balance = str(random_num())
            text = "Thank you. The balance on your "+account+" account is $"+balance+" dollars."
            message =  {
                    'contentType': 'PlainText',
                    'content': text
                }
            fulfillment_state = "Fulfilled"
            return close(intent_request, session_attributes, fulfillment_state, message)

        def FollowupCheckBalance(intent_request):
            session_attributes = get_session_attributes(intent_request)
            slots = get_slots(intent_request)
            account = get_slot(intent_request, 'accountType')
            #The account balance in this case is a random number
            #Here is where you could query a system to get this information
            balance = str(random_num())
            text = "Thank you. The balance on your "+account+" account is $"+balance+" dollars."
            message =  {
                    'contentType': 'PlainText',
                    'content': text
                }
            fulfillment_state = "Fulfilled"
            return close(intent_request, session_attributes, fulfillment_state, message)

        def dispatch(intent_request):
            intent_name = intent_request['sessionState']['intent']['name']
            response = None
            # Dispatch to your bot's intent handlers
            if intent_name == 'CheckBalance':
                return CheckBalance(intent_request)
            elif intent_name == 'FollowupCheckBalance':
                return FollowupCheckBalance(intent_request)

            raise Exception('Intent with name ' + intent_name + ' not supported')

        def lambda_handler(event, context):
            response = dispatch(event)
            return response

  # Add resource policy to allow the Lex Bot Alias to invoke it
  LexBotFunctionPermission:
    Type: AWS::Lambda::Permission
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !GetAtt LexBotFunction.Arn
      Principal: lexv2.amazonaws.com
      SourceArn:
        !Sub "arn:${AWS::Partition}:lex:${AWS::Region}:${AWS::AccountId}:\
              bot-alias/*"

Outputs:
  LexBotId:
    Description: Lex Bot ID
    Value: !Ref LexBot

  LexBotLocaleIds:
    Description: Lex Bot Locale IDs
    Value: !Join [",", !GetAtt LexBot.botLocaleIds]

  LexBotLatestVersion:
    Description: Latest Lex Bot Version ID
    Value: !Ref LexBotVersion

  LexBotAliasId:
    Description: Lex Bot Alias ID
    Value: !Ref LexBotAlias