template.yml

AWSTemplateFormatVersion: 2010-09-09
Description: >-
  file-mgmt

Transform:
- AWS::Serverless-2016-10-31

Globals:
  Function:
    Tracing: Active
    Layers:
      - !Sub "arn:aws:lambda:${AWS::Region}:580247275435:layer:LambdaInsightsExtension:14"

Parameters:
  StageName:
    Type: String
    Default: dev
  BucketName:
    Type: String

Resources:
  AsyncDownload:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/handlers/async-download/
      Handler: app.handler
      Runtime: nodejs14.x
      MemorySize: 128
      Timeout: 120
      Description: A simple example includes a HTTP get method to call a Step Function
      Environment:
        Variables:
          WEB_SOCKET_ENDPOINT: !Join [ "/", [ !GetAtt SimpleAsyncResponseSocket.ApiEndpoint, !Ref Stage ] ]
          CONNECTIONS_TABLE: !Ref DDBConnectionsTable
          STATE_MACHINE_ARN: !Ref ObjectUploaderStateMachine
      Policies:
        - CloudWatchLambdaInsightsExecutionRolePolicy
        - DynamoDBWritePolicy:
            TableName: !Ref DDBConnectionsTable
        - StepFunctionsExecutionPolicy:
            StateMachineName: !GetAtt ObjectUploaderStateMachine.Name
      Events:
        DownloadApiEvent:
          Type: Api
          Properties:
            Path: /download
            Method: GET
            RestApiId: !Ref DownloadApi

  DownloadApi:
    Type: AWS::Serverless::Api
    Properties:
      Name: FileDownloadApi
      Description: The API which clients will use to initiate downloading a large file
      StageName: !Ref StageName
      TracingEnabled: true
      EndpointConfiguration:
        Type: REGIONAL
  
  ObjectUploaderStateMachine:
    Type: AWS::Serverless::StateMachine
    Properties:
      Tracing:
        Enabled: true
      DefinitionUri: statemachine/simple_workflow.asl.json
      DefinitionSubstitutions:
        DownloadS3ObjectFunctionArn: !GetAtt DownloadS3ObjectFunction.Arn
        GetWebSocketConnectionIDFunctionArn: !GetAtt GetWebSocketConnectionIDFunction.Arn
        SendMessageFunctionArn: !GetAtt SendMessageFunction.Arn
      Policies:
        - LambdaInvokePolicy:
            FunctionName: !Ref DownloadS3ObjectFunction
        - LambdaInvokePolicy:
            FunctionName: !Ref GetWebSocketConnectionIDFunction
        - LambdaInvokePolicy:
            FunctionName: !Ref SendMessageFunction

  DownloadS3ObjectFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/handlers/download-s3-object/
      Handler: app.handler
      Runtime: nodejs14.x
      MemorySize: 256
      Timeout: 900
      Environment:
        Variables:
          BUCKET_NAME: !Ref BucketName
      Policies:
        - CloudWatchLambdaInsightsExecutionRolePolicy
        - S3ReadPolicy:
            BucketName: !Ref BucketName
        - S3WritePolicy:
            BucketName: !Ref BucketName

  GetWebSocketConnectionIDFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/handlers/get-websocket-connection/
      Handler: app.handler
      Runtime: nodejs14.x
      Environment:
        Variables:
          CONNECTIONS_TABLE: !Ref DDBConnectionsTable
      Policies:
        - CloudWatchLambdaInsightsExecutionRolePolicy
        - DynamoDBReadPolicy:
            TableName: !Ref DDBConnectionsTable

  DDBConnectionsTable:
    Type: AWS::Serverless::SimpleTable
    Properties:
      PrimaryKey:
        Name: executionArnId
        Type: String
      ProvisionedThroughput:
        ReadCapacityUnits: 2
        WriteCapacityUnits: 2

  # WebSocket API Configurations
  SimpleAsyncResponseSocket:
    Type: AWS::ApiGatewayV2::Api
    Properties:
      Name: SimpleAsyncResponseSocket
      ProtocolType: WEBSOCKET
      RouteSelectionExpression: "$request.body.action"

  ConnectRoute:
    Type: AWS::ApiGatewayV2::Route
    Properties:
      ApiId: !Ref SimpleAsyncResponseSocket
      RouteKey: $connect
      AuthorizationType: NONE
      OperationName: ConnectRoute
      Target: !Join
        - '/'
        - - 'integrations'
          - !Ref ConnectIntegration

  ConnectIntegration:
    Type: AWS::ApiGatewayV2::Integration
    Properties:
      ApiId: !Ref SimpleAsyncResponseSocket
      Description: Connect Integration
      IntegrationType: AWS_PROXY
      IntegrationUri: 
        Fn::Sub:
            arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${OnConnectFunction.Arn}/invocations

  DisconnectRoute:
    Type: AWS::ApiGatewayV2::Route
    Properties:
      ApiId: !Ref SimpleAsyncResponseSocket
      RouteKey: $disconnect
      AuthorizationType: NONE
      OperationName: DisconnectRoute
      Target: !Join
        - '/'
        - - 'integrations'
          - !Ref DisconnectIntegration

  DisconnectIntegration:
    Type: AWS::ApiGatewayV2::Integration
    Properties:
      ApiId: !Ref SimpleAsyncResponseSocket
      Description: Disconnect Integration
      IntegrationType: AWS_PROXY
      IntegrationUri: 
        Fn::Sub:
            arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${OnDisconnectFunction.Arn}/invocations

  SendRoute:
    Type: AWS::ApiGatewayV2::Route
    Properties:
      ApiId: !Ref SimpleAsyncResponseSocket
      RouteKey: sendMessage
      AuthorizationType: NONE
      OperationName: SendRoute
      Target: !Join
        - '/'
        - - 'integrations'
          - !Ref SendIntegration

  SendIntegration:
    Type: AWS::ApiGatewayV2::Integration
    Properties:
      ApiId: !Ref SimpleAsyncResponseSocket
      Description: Send Integration
      IntegrationType: AWS_PROXY
      IntegrationUri: 
        Fn::Sub:
            arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${SendMessageFunction.Arn}/invocations

  Deployment:
    Type: AWS::ApiGatewayV2::Deployment
    DependsOn:
    - ConnectRoute
    - SendRoute
    - DisconnectRoute
    Properties:
      ApiId: !Ref SimpleAsyncResponseSocket

  Stage:
    Type: AWS::ApiGatewayV2::Stage
    Properties:
      StageName: !Ref StageName
      DeploymentId: !Ref Deployment
      ApiId: !Ref SimpleAsyncResponseSocket
      
  OnConnectFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/handlers/on-connect/
      Handler: app.handler
      MemorySize: 256
      Runtime: nodejs14.x
      Environment:
        Variables:
          TABLE_NAME: !Ref DDBConnectionsTable
      Policies:
      - CloudWatchLambdaInsightsExecutionRolePolicy
      - DynamoDBWritePolicy:
          TableName: !Ref DDBConnectionsTable

  OnConnectPermission:
    Type: AWS::Lambda::Permission
    DependsOn:
      - SimpleAsyncResponseSocket
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !Ref OnConnectFunction
      Principal: apigateway.amazonaws.com

  OnDisconnectFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/handlers/on-disconnect/
      Handler: app.handler
      MemorySize: 256
      Runtime: nodejs14.x
      Environment:
        Variables:
          TABLE_NAME: !Ref DDBConnectionsTable
      Policies:
      - CloudWatchLambdaInsightsExecutionRolePolicy
      - DynamoDBCrudPolicy:
          TableName: !Ref DDBConnectionsTable

  OnDisconnectPermission:
    Type: AWS::Lambda::Permission
    DependsOn:
      - SimpleAsyncResponseSocket
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !Ref OnDisconnectFunction
      Principal: apigateway.amazonaws.com

  SendMessageFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/handlers/send-message/
      Handler: app.handler
      MemorySize: 256
      Runtime: nodejs14.x
      Policies:
      - CloudWatchLambdaInsightsExecutionRolePolicy
      - Statement:
        - Effect: Allow
          Action:
          - 'execute-api:ManageConnections'
          Resource:
          - !Sub 'arn:aws:execute-api:${AWS::Region}:${AWS::AccountId}:${SimpleAsyncResponseSocket}/*'

  SendMessagePermission:
    Type: AWS::Lambda::Permission
    DependsOn:
      - SimpleAsyncResponseSocket
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !Ref SendMessageFunction
      Principal: apigateway.amazonaws.com

Outputs:
  WebEndpoint:
    Description: "API Gateway endpoint URL"
    Value: !Sub "https://${DownloadApi}.execute-api.${AWS::Region}.amazonaws.com/${StageName}/"

  WebSocketEndpoint:
    Description: "WebSocket API Gateway endpoint URL"
    Value: !Join [ "/", [ !GetAtt SimpleAsyncResponseSocket.ApiEndpoint, !Ref Stage ] ]