Lambda Layers

Basic example for AWS Lambda layers with serverless and node. It creates a Lambda function with two layers. A Business layer with custom code and a dependencies layer with node libraries.

Deploy

Requirements

You need a AWS account and the serverless cli and npm running.

Deploy Layers

To deploy the setup and deploy the layers you can run the setup-deploy-layers.sh or execute the commands on your own.

# install business code
(cd lambda-layers/businesslayer/nodejs; npm install)
# install dependencies code
(cd lambda-layers/dependencieslayer/nodejs; npm install)
# deploy layers
(cd lambda-layers; sls deploy)

Deploy Function

To deploy the function with layers you have to update the version arn of the layers at the lambda-layers-functions/serverless.yml

functions:
  hello:
    handler: src/app/handler.hello
    layers: # layer refs
      - 'Fn::Join': # specify the business layer arn
         - ':'
         - - 'arn:aws:lambda'
           - Ref: 'AWS::Region'
           - Ref: 'AWS::AccountId'
           - 'layer'
           - 'dev-business-layer' # layer name
           - '2' # version to update
      - 'Fn::Join': # specify the dependencies layer arn
         - ':'
         - - 'arn:aws:lambda'
           - Ref: 'AWS::Region'
           - Ref: 'AWS::AccountId'
           - 'layer'
           - 'dev-dependencies-layer' # layer name
           - '3' # version to update

then you can run (cd lambda-layer-functions; sls deploy) to deploy the Function