AWS Lambda: Support ImageConfig properties

There is new image: option that can create AWS Lambda function based on docker container image. It would be nice to support image_config as well, to override image Command, EntryPoint and WorkingDirectory.

functions:
  hello:
    image: ${env:DOCKER_IMAGE}
   
  hello2:
    image: ${env:DOCKER_IMAGE}
    image_config:
      command: ["app.handler2"]

or even

provider:
  image: ${env:DOCKER_IMAGE}
functions:
  hello:
    image_config:
      command: ["app.handler"]
  hello2:
    image_config:
      command: ["app.handler2"]
      working_dir: "/var/task/experimental"
  hello3:
    image_config:
      command: ["app.swift_handler"]
      entry_point: 
         - /var/runtime/swift_bootstrap

Use case description

It would be possible to share one docker image and choose specific handler per lambda function. It would be event better if provider section allows to define global image, shared between all lambda functions that contain image_config parameter. Similar like it’s done for layers.

Proposed solution

At the moment you can achieve similar thing overriding LambdaFunction in Resources

service: sls-container-image-test
useDotenv: true
provider: 
  name: aws
  region: ap-northeast-1

functions:
  hello:
    image: ${env:DOCKER_IMAGE}
  hello2:
    image: ${env:DOCKER_IMAGE}

resources:
  Resources:
    Hello2LambdaFunction:
      Type: AWS::Lambda::Function
      Properties: 
        ImageConfig:
          EntryPoint: 
            - /var/runtime/bootstrap
          Command: ["app.handler2"]

[medikoo]

@arekt great thanks for proposal. We’re definitely open for it, still to be more on par with current conventions I believe it should be configured in a way that we expand already defined image property, So extended configuration we could look as follows:

functions:
  hello:
    image:
      uri: 000000000000.dkr.ecr.sa-east-1.amazonaws.com/test-lambda-docker@sha256:6bb600b4d6e1d7cf521097177dd0c4e9ea373edb91984a505333be8ac9455d38
      command: ...
      workingDir: ...

What do you think?

Also what exactly properties do you believe we should support, and how will they map to generated CloudFormation template?

[medikoo]

@NaveenTartLabs For general support please check:

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