aws-lambda powertools cdk

README.md

Welcome to your CDK Python project!

This is a blank project for Python development with CDK.

The cdk.json file tells the CDK Toolkit how to execute your app.

Install dependencies by running

$ make dev

At this point you can now synthesize the CloudFormation template for this code.

$ cdk synth

To add additional dependencies, for example other CDK libraries, just add them using poetry add

Useful commands

• cdk ls list all stacks in the app
• cdk synth emits the synthesized CloudFormation template
• cdk deploy deploy this stack to your default AWS account/region
• cdk diff compare deployed stack with current state
• cdk docs open CDK documentation

Enjoy!

app.py

# cdk/app.py
from aws_cdk import core as cdk
from lambda_stack.lambda_stack import LambdaStack

app = cdk.App()
LambdaStack(app, "LambdaStack")
app.synth()

cdk.json

{
  "app": "poetry run python3 app.py",
  "context": {
    "powertools_version": "1.13.0"
  }
}

lambda_stack.py

# cdk/lambda_stack/lambda_stack.py
import pathlib

import aws_cdk.aws_lambda as aws_lambda
import aws_cdk.aws_sam as sam
from aws_cdk import core as cdk


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

        lambda_src_dir = str(pathlib.Path(__file__).parent.parent.parent) + "/hello-world/"

        # Reference the Layer in a Lambda definition
        aws_lambda.Function(
            self,
            "MyFunction",
            layers=[self.get_powertools_lambda_layer()],
            runtime=aws_lambda.Runtime.PYTHON_3_8,
            handler="app.lambda_handler",
            code=aws_lambda.Code.from_asset(lambda_src_dir),
        )

    def get_powertools_lambda_layer(self):
        powertools_version = self.node.try_get_context("powertools_version")
        powertools_arn = "arn:aws:serverlessrepo:eu-west-1:057560766410:applications/aws-lambda-powertools-python-layer"
        powertools_application = sam.CfnApplication(
            self,
            "AWSLambdaPowertoolsApplication",
            location={
                "applicationId": powertools_arn,
                "semanticVersion": powertools_version,
            },
        )
        powertools_resource = cdk.CfnResource(
            powertools_application,
            "AWSLambdaPowertoolsResource",
            type="AWS::Serverless::Application",
            properties={
                "Location": {
                    "ApplicationId": powertools_arn,
                    "SemanticVersion": powertools_version,
                }
            },
        )
        return aws_lambda.LayerVersion.from_layer_version_arn(
            self,
            "AWSLambdaPowertoolsLayer",
            powertools_resource.get_att("Outputs.LayerVersionArn").to_string(),
        )

Makefile

# cdk/Makefile
dev:
  # Installs peotry and the dependencies
	pip install --upgrade pip poetry
	poetry install

pyproject.toml

[tool.poetry]
name = "cdk"
version = "0.1.0"
description = "CDK code for the hello world example"
authors = ["Michael Brewer <michael.brewer@gyft.com>"]

[tool.poetry.dependencies]
python = "^3.8"
"aws-cdk.core" = "^1.96.0"
"aws-cdk.aws-sam" = "^1.96.0"
"aws-cdk.aws-lambda" = "^1.96.0"

[tool.poetry.dev-dependencies]

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"