Can not build container using Dockerfile

[bardiakhosravi]

Trying to use a Dockerfile so that I can install Pycairo on Lambda.

Using serverless-python-requirements to build.

Here the pythonRequirements config in serverless.yml

custom:
  pythonRequirements:
    dockerizePip: true
    dockerFile: ./Dockerfile
    useDownloadCache: false
    useStaticCache: false

And this is the Dockerfile

FROM public.ecr.aws/lambda/python:3.8

RUN yum -y install gcc cairo-devel

and the pyproject.toml is:

[tool.poetry]
name = "my-service-name"
version = "0.1.0"
description = ""
authors = [""]

[tool.poetry.dependencies]
python = "^3.8"
pycairo = "^1.21.0"
serpy = "^0.3.1"
simplejson = "^3.17.6"
palettable = "^3.3.0"

[tool.poetry.dev-dependencies]
...

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

after running sls deploy -s dev I get the following error:

entrypoint requires the handler name to be the first argument

Does anyone know why? and what I have done wrong?

Thank you for your help.

[pgrzesik]

Hey @bardiakhosravi 👋 Could you please share the reproducible example with serverless.yml content? Are you trying to use the same Docker image as image that function uses as runtime?

[bardiakhosravi]

unfortunately removing the handler field did not change anything. The updated serverless.yml is

functions:
  api:
    image:
      name: baseimage
      workingDirectory: my_service/host/api
      command:
        - handler.route
    layers:
      - arn:aws:lambda:us-east-1:770693421928:layer:Klayers-p38-numpy:7
      - arn:aws:lambda:us-east-1:770693421928:layer:Klayers-p38-matplotlib:10
      - arn:aws:lambda:us-east-1:770693421928:layer:Klayers-p38-Pillow:4
    events:
      - httpApi:
          path: /env
          method: GET

I still see the error

The "path" argument must be of type string or an instance of Buffer or URL. Received undefined

[bardiakhosravi]

trying to build the docker by providing a path to the dockerfile and building all requirements in the dockerfile without using serverless-python-requirements.

  ecr:
    images:
      apiimage:
        path: ./

[pgrzesik]

When you are using image, then serverless-python-requirements plugin doesn't really do anything for you. You need to install all the dependencies manually when configuring your Dockerfile.

[bardiakhosravi]

Yes. I just realized that :)

Thank you for your help. I managed to build the image successfully.

[pgrzesik]

Happy to hear that 🥳