Containerized AWS Lambda

Lambda Deployment Packages

Lambda supports two types of deployment packages: container images and .zip file archives.

A container image includes the base operating system, the runtime, Lambda extensions, your application code and its dependencies.
A .zip file archive includes your application code and its dependencies. When you author functions using the Lambda console or a toolkit, Lambda automatically creates a .zip file archive of your code.

Creating Lambda container image

The activity can be achieved in the following steps:

Create a project directory for your new function on your system.
Create a directory named app in the project directory, and then add your function handler code to the app directory in a file called app.rb.

Create a new Dockerfile with the content as below:

FROM public.ecr.aws/lambda/ruby:2.7

# Copy function code
COPY app.rb ${LAMBDA_TASK_ROOT}

# Copy dependency management file
COPY Gemfile ${LAMBDA_TASK_ROOT}

# Install dependencies under LAMBDA_TASK_ROOT
ENV GEM_HOME=${LAMBDA_TASK_ROOT}
ENV HOME="/tmp"

RUN yum install -y gcc make gcc-c++ git unzip &&\
 # Install gem dependencies with bundler
 bundle install &&\
 # Uninstall yum packages that will no longer be needed
 yum remove -y gcc make gcc-c++ unzip &&\
 # Clear out yum cache to save additional space
 yum clean all &&\
 rm -rf /var/cache/yum


# Set the CMD to your handler (could also be done as a parameter override outside of the Dockerfile)
CMD [ "app.lambda_handler" ]

Build your Docker image with the docker build command. Enter a name for the image. The following example names the image hello-world.

docker build -t hello-world .
Start the Docker image with the docker run command. For this example, enter hello-world as the image name.

docker run -p 9000:8080 hello-world
Test your application locally using the runtime interface emulator. From a new terminal window, post an event to the following endpoint using a curl command:

curl -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{}'

This command invokes the function running in the container image and returns a response.

Upload the image to the Amazon ECR repository

In the following commands, replace 123456789012 with your AWS account ID and set the region value to the region where you want to create the Amazon ECR repository.

Note In Amazon ECR, if you reassign the image tag to another image, Lambda does not update the image version.

Authenticate the Docker CLI to your Amazon ECR registry.

aws ecr get-login-password --region us-east-1 | docker login --username AWS --password-stdin 123456789012.dkr.ecr.us-east-1.amazonaws.com
Create a repository in Amazon ECR using the create-repository command.

aws ecr create-repository --repository-name hello-world --image-scanning-configuration scanOnPush=true --image-tag-mutability MUTABLE
Tag your image to match your repository name.

docker tag hello-world:latest 123456789012.dkr.ecr.us-east-1.amazonaws.com/hello-world:latest
Deploy the image to Amazon ECR using the docker push command.

docker push 123456789012.dkr.ecr.us-east-1.amazonaws.com/hello-world:latest

Now that your container image resides in the Amazon ECR container registry, you can create and run the Lambda function.

Lambda Deployment Packages

Creating Lambda container image

Upload the image to the Amazon ECR repository

References