master.yaml

AWSTemplateFormatVersion: 2010-09-09
Description: |
    Master Lex Web UI CloudFormation template (v0.14.8)
    It deploys:
        - S3 buckets to host the web application
        - CodeBuild project to build the configuration and deploy to S3
        - Optional Lex Bot (based on OrderFlowers example)
        - Optional Cognito Identity Pool for unauthenticated identities
        - Optional Lambda function to delete S3 buckets
        - CloudWatch Logs groups related to Lambda functions
        - Associated IAM roles

Parameters:
    BotName:
        Description: >
            Name of an existing Lex Bot to be used by the web ui.
            This is an optional parameter. If left empty, a Bot based
            on the OrderFlowers sample will be automatically created.
        Type: String
        Default: ''
        MaxLength: 50
        AllowedPattern: '(^$|^[a-zA-Z]+((_[a-zA-Z]+)*|([a-zA-Z]+_)*|_))'
        ConstraintDescription: >
            Must conform with the permitted Lex Bot name pattern.

    BotAlias:
        Description: >
            Alias to use of an existing Lex Bot. By default this is '$LATEST'.
            Use this default if the lex-web-ui should always use the most
            recent version of the bot.
        Type: String
        Default: '$LATEST'
        MinLength: 2
        MaxLength: 50
        AllowedPattern: '(^$|^[$a-zA-Z]+((_[$a-zA-Z]+)*|([$a-zA-Z]+_)*|_))'
        ConstraintDescription: >
            Must conform with the permitted Lex Alias name pattern.

    BotNamePrefix:
        Type: String
        Description: >
            Prefix to add to Lex resource names when using the sample bot.
            Ignored if you provide your own bot. Must conform to the
            permitted Lex Bot name syntax (alpha characters).
        Default: WebUi
        MinLength: 3
        MaxLength: 32
        AllowedPattern: '^[a-zA-Z\._]+$'
        ConstraintDescription: >
            Must conform with the permitted Lex Bot name pattern.

    ShouldDeleteBot:
        Type: String
        Default: true
        AllowedValues:
          - true
          - false
        Description: >
            If set to True, the Lex bot and associated resources will
            be deleted when the stack is deleted. Otherwise, the bot
            will be preserved. Only applies if the bot is created by
            this stack.

    EnableCognitoLogin:
        Type: String
        Default: false
        AllowedValues:
          - true
          - false
        Description: >
            If set to True, a menu with a login action will be displayed
            in the Lex Web Ui. This feature uses Cognito User Pools with
            hosted login pages. After login, the menu will switch to logout.

    CodeBuildName:
        Type: String
        Description: >
            Name of the CodeBuild project to be created. Used to
            configure and directly deploy the web app to S3. Must be
            unique per region
        Default: lex-web-ui
        MinLength: 2
        MaxLength: 255
        AllowedPattern: '^[A-Za-z0-9][A-Za-z0-9\-_]{1,254}$'
        ConstraintDescription: >
            Should start with Alphanumeric. May contain alphanumeric, undescore
            and dash.

    WebAppParentOrigin:
        Type: String
        Description: >
            Browser origin (e.g. http://mysite.example.com:8080)
            of an existing site that is allowed to send/receive data
            and events from the web ui in an iframe setup. This is an
            optional parameter. If left empty, the sample parent page
            will be hosted in the same S3 bucket as the iframe
        Default: ''
        AllowedPattern: '(^$|^https?://[\w\.-]+(:\d+)?$)'
        ConstraintDescription: Empty or valid browser origin

    WebAppPath:
        Type: String
        Default: '/parent.html'
        Description: >
            Path to the page hosting the sample WebApp. This parameter defaults
            to parent.html which is used by the sample app created when hosting the
            bot in a separate iframe. This path should be updated to reflect the
            path to the default (home) page used by the WebAppParentOrigin.
            This may be /index.html rather than the default.

    CognitoIdentityPoolId:
        Type: String
        Description: >
            Id of an existing Cognito Identity Pool. This is an optional
            parameter. If left empty, a Cognito Identity Pool will be
            automatically created. The pool ID is used by the web ui
            to get AWS credentials for making calls to Lex and Polly.
        Default: ''
        AllowedPattern: '(^$|^[\w-]+:[0-9a-f-]+$)'
        ConstraintDescription: Empty or a valid Cognito Identity Pool ID

    CognitoIdentityPoolName:
        Type: String
        Description: >
            Name of Cognito identity pool to be created to provide
            AWS credentials to the web ui. Only used if the
            CognitoIdentityPoolId parameter is left empty (default).
        Default: Lex Web UI
        MinLength: 1
        MaxLength: 128
        AllowedPattern: '^[\w ]+$'
        ConstraintDescription: Alphanumeric and spaces.

    CleanupBuckets:
        Type: String
        Default: true
        AllowedValues:
          - true
          - false
        Description: >
            If set to True, buckets created for the Pipeline and to store the
            web application will be deleted on CloudFormation stack delete.
            If set to False, S3 buckets will be retained.

    EnableMarkdownSupport:
        Type: String
        Default: true
        AllowedValues:
        - true
        - false
        Description: >
            If set to True, enable optional Markdown formatting.
            Warning: Improper use of the Markdown/html feature can open you up to a cross-site
            scripting (XSS) attack from insecure Bots. Make sure you trust the Bot being used
            by the LexWebUi.

    ReInitSessionAttributesOnRestart:
        Type: String
        Default: false
        AllowedValues:
        - true
        - false
        Description: >
            If set to True, session attributes sent on each request to Lex are reset. Use a value
            of false, if session attributes need to be supported on subsequent Lex requests. The
            default is false.

    ShouldLoadIframeMinimized:
        Type: String
        Default: false
        AllowedValues:
        - true
        - false
        Description: >
            If set to True and running embedded as an Iframe on a web page, minimize the
            LexWebUi when first launched. If set to False, the Iframe will be maximized
            on the hosting page.

    ShowResponseCardTitle:
        Type: String
        Default: true
        AllowedValues:
        - true
        - false
        Description: >
            If set to True, the ResponseCard title is displayed in the UI. When set to false,
            a ResponseCard title is not displayed in the UI. Default is true. Note at the
            present time this is a global setting. Should the UI need to display some form
            of a title, use the optional sub-title property of a ResponseCard.

    # Sub-templates and source artifacts are hosted in this bucket.
    # The content of this bucket is maintained outside of this template
    # by using the Makefile under the build directory of this project.
    # See the README.md file for instructions on how to use your own bucket.
    BootstrapBucket:
        Type: String
        Default: aws-bigdata-blog
        Description: >
            S3 bucket containing pre-staged nested templates and source artifacts
    BootstrapPrefix:
        Type: String
        Default: artifacts/aws-lex-web-ui/artifacts
        Description: >
            S3 prefix where the templates and source are stored under

    WebAppConfBotInitialText:
        Type: String
        Default: >
            You can ask me for help ordering flowers. Just type "Buy
            flowers" or click on the mic and say it.
        Description: First bot message displayed in the chatbot UI

    WebAppConfBotInitialSpeech:
        Type: String
        Default: Say 'Buy Flowers' to get started.
        Description: >
            Message spoken by bot when the microphone is first pressed in
            a conversation
    
    WebAppConfNegativeFeedback:
        Type: String
        Default: Thumbs down
        Description: >
            This optional parameter defines the message to be sent by the user upon pressing 
            a feedback button signaling a negative feedback.
            If left empty feedback buttons will be disabled on the UI.

    WebAppConfPositiveFeedback:
        Type: String
        Default: Thumbs up
        Description: >
            This optional parameter defines the message to be sent by the user upon pressing 
            a feedback button signaling a positive feedback.
            If left empty feedback buttons will be disabled on the UI.
    
    WebAppConfHelp:
        Type: String
        Default: Help
        Description: >
            This is an optional parameter, when defined with a value, a help button will display on the chat bot toolbar.
            When pressed the button will send the entered string to the bot as a help message.  If left empty
            the help button will be disabled.
        
    WebAppConfToolbarTitle:
        Type: String
        Default: Order Flowers
        Description: Title displayed in the chatbot UI toolbar

Metadata:
    AWS::CloudFormation::Interface:
        ParameterGroups:
            - Label:
                default: Deployment Parameters
              Parameters:
                  - CodeBuildName
                  - CleanupBuckets
                  - BootstrapBucket
                  - BootstrapPrefix
            - Label:
                default: Lex Bot Configuration Parameters
              Parameters:
                  - BotName
                  - BotAlias
                  - BotNamePrefix
                  - ShouldDeleteBot
                  - EnableCognitoLogin
                  - EnableMarkdownSupport
                  - ReInitSessionAttributesOnRestart
                  - ShowResponseCardTitle
            - Label:
                default: Cognito Parameters
              Parameters:
                  - CognitoIdentityPoolId
                  - CognitoIdentityPoolName
            - Label:
                default: Web Application Parameters
              Parameters:
                  - WebAppParentOrigin
                  - WebAppPath
                  - WebAppConfBotInitialText
                  - WebAppConfBotInitialSpeech
                  - WebAppConfNegativeFeedback
                  - WebAppConfPositiveFeedback
                  - WebAppConfHelp
                  - WebAppConfToolbarTitle
                  - ShouldLoadIframeMinimized
Conditions:
    NeedsBot: !Equals [!Ref BotName, '']
    NeedsCognito: !Equals [!Ref CognitoIdentityPoolId, '']
    NeedsParentOrigin: !Equals [!Ref WebAppParentOrigin, '']

Resources:
    Bot:
        Type: AWS::CloudFormation::Stack
        Condition: NeedsBot
        Properties:
            TimeoutInMinutes: 15
            TemplateURL: !Sub "https://s3.amazonaws.com/${BootstrapBucket}/${BootstrapPrefix}/templates/lexbot.yaml"
            Parameters:
                NamePrefix: !Ref BotNamePrefix
                ShouldDeleteBot: !Ref ShouldDeleteBot
                CustomResourceCodeBucket: !Ref BootstrapBucket
                CustomResourceCodeObject: !Sub "${BootstrapPrefix}/custom-resources.zip"

    CognitoIdentityPool:
        Type: AWS::CloudFormation::Stack
        Condition: NeedsCognito
        Properties:
            TemplateURL: !Sub "https://s3.amazonaws.com/${BootstrapBucket}/${BootstrapPrefix}/templates/cognito.yaml"
            Parameters:
                CognitoIdentityPoolName: !Ref CognitoIdentityPoolName
                LexBotName:
                    !If
                      - NeedsBot
                      - !GetAtt Bot.Outputs.BotName
                      - !Ref BotName

    ##########################################################################
    # Simplified deployment using CodeBuild to build config and push to S3
    ##########################################################################
    CodeBuildDeploy:
        Type: AWS::CloudFormation::Stack
        Properties:
            TemplateURL: !Sub "https://s3.amazonaws.com/${BootstrapBucket}/${BootstrapPrefix}/templates/codebuild-deploy.yaml"
            Parameters:
                CodeBuildName: !Ref CodeBuildName
                SourceBucket: !Ref BootstrapBucket
                SourceObject: !Sub "${BootstrapPrefix}/src.zip"
                CustomResourceCodeObject: !Sub "${BootstrapPrefix}/custom-resources.zip"
                CleanupBuckets: !Ref CleanupBuckets
                BotName:
                    !If
                      - NeedsBot
                      - !GetAtt Bot.Outputs.BotName
                      - !Ref BotName
                BotAlias: !Ref BotAlias
                CognitoIdentityPoolId:
                    !If
                      - NeedsCognito
                      - !GetAtt CognitoIdentityPool.Outputs.CognitoIdentityPoolId
                      - !Ref CognitoIdentityPoolId
                ParentOrigin: !Ref WebAppParentOrigin
                WebAppConfBotInitialText: !Ref WebAppConfBotInitialText
                WebAppConfBotInitialSpeech: !Ref WebAppConfBotInitialSpeech
                WebAppConfNegativeFeedback: !Ref WebAppConfNegativeFeedback
                WebAppConfPositiveFeedback: !Ref WebAppConfPositiveFeedback
                WebAppConfHelp: !Ref WebAppConfHelp
                WebAppConfToolbarTitle: !Ref WebAppConfToolbarTitle
                ShouldEnableCognitoLogin: !Ref EnableCognitoLogin
                ReInitSessionAttributesOnRestart: !Ref ReInitSessionAttributesOnRestart
                EnableMarkdownSupport: !Ref EnableMarkdownSupport
                ShouldLoadIframeMinimized: !Ref ShouldLoadIframeMinimized
                ShowResponseCardTitle: !Ref ShowResponseCardTitle
                CognitoAppUserPoolClientId:
                    !If
                      - NeedsCognito
                      - !GetAtt CognitoIdentityPool.Outputs.CognitoUserPoolClientId
                      - "UserMustSupply"
                CognitoUserPoolId:
                    !If
                      - NeedsCognito
                      - !GetAtt CognitoIdentityPool.Outputs.CognitoUserPoolId
                      - "UserMustSupply"


    CognitoIdentityPoolConfig:
        Type: AWS::CloudFormation::Stack
        Condition: NeedsCognito
        Properties:
            TemplateURL: !Sub "https://s3.amazonaws.com/${BootstrapBucket}/${BootstrapPrefix}/templates/cognitouserpoolconfig.yaml"
            Parameters:
                WebAppUrl: !If [NeedsParentOrigin, !GetAtt CodeBuildDeploy.Outputs.WebAppBase, !Ref WebAppParentOrigin]
                WebAppPath: !Ref WebAppPath
                CodeBuildProjectName: !GetAtt CodeBuildDeploy.Outputs.CodeBuildProject
                CognitoUserPool: !GetAtt CognitoIdentityPool.Outputs.CognitoUserPoolId
                CognitoUserPoolClient: !GetAtt CognitoIdentityPool.Outputs.CognitoUserPoolClientId

Outputs:
    BotName:
        Condition: NeedsBot
        Description: >
            Name of the Lex bot created by the stack
        Value: !GetAtt Bot.Outputs.BotName

    CodeBuildUrl:
        Description: >
            Monitor the pipeline URL to see when the application has been fully
            built and deployed.
        Value: !Sub "https://console.aws.amazon.com/codebuild/home?region=${AWS::Region}#/projects/${CodeBuildDeploy.Outputs.CodeBuildProject}/view"

    WebAppUrl:
        Description: >
            URL of the stand-alone sample web application.
            This page will be available after the pipeline/deployment completes.
        Value: !GetAtt CodeBuildDeploy.Outputs.WebAppUrl

    ParentPageUrl:
        Condition: NeedsParentOrigin
        Description: >
            URL of the iframe based sample web application
            This page will be available after the pipeline/deployment completes.
        Value: !GetAtt CodeBuildDeploy.Outputs.ParentPageUrl

    LoaderScriptUrl:
        Description: >
            URL of the loader script
            This script will be available after the pipeline/deployment completes.
        Value: !GetAtt CodeBuildDeploy.Outputs.LoaderScriptUrl

    SnippetUrl:
        Description: >
            URL of a page showing the snippet to load the chatbot UI as
            an iframe
        Value: !GetAtt CodeBuildDeploy.Outputs.SnippetUrl

    CognitoIdentityPoolId:
        Condition: NeedsCognito
        Description: Cognito Identity Pool Id
        Value: !GetAtt CognitoIdentityPool.Outputs.CognitoIdentityPoolId
    
    CognitoUserPoolPubKey:
        Condition: NeedsCognito
        Description: Include Cognito User Pool Public Key URL in stack outputs (needed for QnABot token auth)
        Value: !Sub https://cognito-idp.${AWS::Region}.amazonaws.com/${CognitoIdentityPool.Outputs.CognitoUserPoolId}/.well-known/jwks.json