Deploy a Docker built Lambda function with AWS CDK

This project is a minimum working example of deploying an AWS Lambda function using Docker and AWS CDK.

Deploying Lambda functions using Docker has a number of benefits

  • Package all necessary libraries into a single Docker image

  • Bypass AWS Lambda's size constraint of 512 mb. Docker images stored on AWS ECR have a maximum size of 10 gb.

  • It’s easy!

The Dev.to article can be found here

If starting from scratch

  1. mkdir project && cd project
  2. cdk init --language python
  3. Follow instructions below to activate venv, install libraries.
  4. Make sure you have activated your AWS credentials and cdk deploy

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.

This project is set up like a standard Python project. The initialization process also creates a virtualenv within this project, stored under the .venv directory. To create the virtualenv it assumes that there is a python3 (or python for Windows) executable in your path with access to the venv package. If for any reason the automatic creation of the virtualenv fails, you can create the virtualenv manually.

To manually create a virtualenv on MacOS and Linux:

$ python -m venv .venv

After the init process completes and the virtualenv is created, you can use the following step to activate your virtualenv.

$ source .venv/bin/activate

If you are a Windows platform, you would activate the virtualenv like this:

% .venv\Scripts\activate.bat

Once the virtualenv is activated, you can install the required dependencies.

$ pip install -r requirements.txt

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 to your setup.py file and rerun the pip install -r requirements.txt command.

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!