AWS API Gateway WebSocket route configured for two way request/response.

snippte-template.yaml

########## Default Route ($default) Function and APIGW Config ############

  DefaultFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: default/
      Handler: bootstrap       # note, this is the name of the executable output from the Makefile.
      Runtime: provided.al2
      Architectures: [ arm64 ]
      Policies:
        - AWSLambdaBasicExecutionRole
    Metadata:
      BuildMethod: makefile

  DefaultRoute:
    Type: AWS::ApiGatewayV2::Route
    Properties:
      ApiId: !Ref Api
      RouteKey: "$default"
      Target: !Join
        - '/'
        - - 'integrations'
          - !Ref DefaultLambdaIntegration
 
  DefaultFunctionPermission:
    Type: AWS::Lambda::Permission
    DependsOn:
      - Api
      - DefaultFunction
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !Ref DefaultFunction
      Principal: apigateway.amazonaws.com

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

  DefaultRouteResponse:
    Type: AWS::ApiGatewayV2::RouteResponse
    Properties:
      RouteId: !Ref DefaultRoute
      ApiId: !Ref Api
      RouteResponseKey: "$default"

  DefaultIntegrationResponse:
    Type: AWS::ApiGatewayV2::IntegrationResponse
    Properties:
      IntegrationId: !Ref DefaultLambdaIntegration
      IntegrationResponseKey: "$default"
      ApiId: !Ref Api