def __init_

def init()

in apigw-canary-deployment-cdk/app.py [0:0]
62 lines of code
3 McCabe index (conditional complexity)

    def __init__(self, scope: cdk.Construct, construct_id: str, **kwargs) -> None:
        super().__init__(scope, construct_id, **kwargs)

        # Create a Lambda function
        # Code in ./src directory
        lambda_fn = lambda_.Function(
            self, "MyFunction",
            runtime=lambda_.Runtime.PYTHON_3_9,
            handler="index.handler",
            code=lambda_.Code.from_asset(os.path.join(DIRNAME, "src"))
        )

        # Function version
        version = lambda_fn.current_version

        # Create function alias
        alias = lambda_.Alias(
            self, "LambdaAlias",
            alias_name="Prod",
            version=version
        )

        # Create the Rest API
        rest_api = apigateway.RestApi(
            self, "RestApi",
            endpoint_types=[apigateway.EndpointType.REGIONAL],
            deploy=False,
            retain_deployments=False
        )

        # Create initial deployment
        deployment = apigateway.Deployment(
            self,
            "Deployment",
            api=rest_api,
            retain_deployments=False
        )

        # Create prod Stage
        stage = apigateway.Stage(
            self,
            "prod",
            deployment=deployment,
            variables={
                "lambdaAlias": "Prod"
            }
        )

        rest_api.deployment_stage = stage

        # Create URI for lambda alias
        stage_uri = f"arn:aws:apigateway:{cdk.Aws.REGION}:lambda:path/2015-03-31/functions/{lambda_fn.function_arn}:${{stageVariables.lambdaAlias}}/invocations"

        # Create Lambda Integration
        integration = apigateway.Integration(
            type=apigateway.IntegrationType.AWS_PROXY,
            integration_http_method="POST",
            uri=stage_uri
        )

        # Create APIGW Method
        method = rest_api.root.add_method("GET", integration)

        # Add Lambda permissions
        lambda_fn.add_permission(
            "lambdaPermission",
            action="lambda:InvokeFunction",
            principal=iam.ServicePrincipal("apigateway.amazonaws.com"),
            source_arn=method.method_arn.replace(
                rest_api.deployment_stage.stage_name, "*"
            )
        )

        # Add permissions for Prod alias
        alias.add_permission(
            "aliasPermission",
            action="lambda:InvokeFunction",
            principal=iam.ServicePrincipal("apigateway.amazonaws.com"),
            source_arn=method.method_arn.replace(
                rest_api.deployment_stage.stage_name, "*"
            )
        )

        # OUTPUTS
        cdk.CfnOutput(self, "LambdaFunction", export_name="MyLambdaFunction", value=lambda_fn.function_arn)
        cdk.CfnOutput(self, "ApigwId", export_name="MyAPIGWID", value=rest_api.rest_api_id)
        cdk.CfnOutput(self, "MethodArn", export_name="MyMethodArn", value=method.method_arn)
        cdk.CfnOutput(self, "StageName", export_name="MyStageName", value=rest_api.deployment_stage.stage_name)
def __init__()

def init()
