what does a "non" parameterised (seperate BUILD) file inference look like ?

right now I have the below - but that will need to change when the image changes in CI/CD

version_and_changelog(hyphenated_format=True)

docker_image(
  name="mything",
  repository="mything",
  image_tags=["{build_args.DEFAULT_TAG}"],
  extra_build_args=["BASE_IMAGE=registry.internal/library/python:3.10-slim"],
  dependencies= [
    ...,
    "//common/base-containers:images-python@parametrize=py310deb",
  ],
)

Filed: https://github.com/pantsbuild/pants/issues/20632

Fix: https://github.com/pantsbuild/pants/pull/20633

once that's in, to answer the original question (for the record) both of these should then work:

# ARG BASE_IMAGE=common/base-containers:images-python@parametrize=py310deb
# ARG BASE_IMAGE=//common/base-containers:images-python@parametrize=py310deb

what does a "non" parameterised (seperate BUILD) file inference look like ?

not sure what you mean here... it's the same, only difference is the address used for the build ARG value in the Dockerfile instruction. Or this became a non-question now that we know you hit a bug? 🙂

@curved-television-6568 - I have some testing data now for you - which makes it clear where / and how parametrized and injected images names do and don't work. Context: I am using pants 2.20.0rc1 which has the fix for https://github.com/pantsbuild/pants/pull/20633 In summary the

pants docker base_image (FROM via ARGS)

mechanism the build-arg BASE_IMAGE/ARG can either be - static, repository reachable, images inside the Dockerfile - static, inside the Dockerfile - pants targets, (relative, absolute, and parametrized) - "dynamic", passed in via the extra_build_args, ONLY if FROM image value is a : repository reachable, images inside the Dockerfile (not a pants inferenced one) to be clear, target inference only works on the static Dockerfile, it does not update, or make changes to any "args" being passed to

docker .. --build_args

I have posted the working example here https://github.com/rbuckland/pants-playground/tree/explore/docker-image-parametrize?tab=readme-ov-file#2-exploring-pants-target-docker-inference

for clarity This is the output run (but you need to see the BUILD and Dockerfiles to understand what is happening)

❯ pants list containers/sample:: | xargs -Ixx sh -c "echo ======= xx; pants package xx 2>&1 | sed 's#^#  #'"
======= containers/sample:sample-external-image-via-build_args
  08:10:44.95 [INFO] Starting: Building docker image sample-external-image-via-build_args:latest
  08:10:53.83 [INFO] Completed: Building docker image sample-external-image-via-build_args:latest
  08:10:53.84 [INFO] Wrote dist/containers.sample/sample-external-image-via-build_args.docker-info.json
  Built docker image: sample-external-image-via-build_args:latest
  Docker image ID: sha256:fed834eb510decd18e8cdc0e4abf9b1d8ecb293f58941cd616f7725ce0e00479
======= containers/sample:sample-other-pants-tgt-basic-image-relative-via-build_args
  08:11:00.68 [INFO] Starting: Building docker image python:3.11-slim
  08:11:03.16 [INFO] Completed: Building docker image python:3.11-slim
  08:11:03.16 [INFO] Starting: Building docker image sample-other-pants-tgt-basic-image-relative-via-build_args:latest
  08:11:05.01 [INFO] Completed: Building docker image sample-other-pants-tgt-basic-image-relative-via-build_args:latest
  08:11:05.01 [WARN] Docker build failed for `docker_image` containers/sample:sample-other-pants-tgt-basic-image-relative-via-build_args. There are files in the Docker build context that were not referenced by any `COPY` instruction (this is not an error):

    * containers.common/python-3-11-basic.docker-info.json
    * my_simple_lib-4.3.1-py3-none-any.whl
    * my_simple_lib-4.3.1.tar.gz


  08:11:05.01 [ERROR] 1 Exception encountered:

  Engine traceback:
    in `package` goal

  ProcessExecutionFailure: Process 'Building docker image sample-other-pants-tgt-basic-image-relative-via-build_args:latest' failed with exit code 1.
  stdout:

  stderr:
  #0 building with "default" instance using docker driver

  #1 [internal] load .dockerignore
  #1 transferring context: 2B done
  #1 DONE 0.0s

  #2 [internal] load build definition from Dockerfile
  #2 transferring dockerfile: 115B done
  #2 DONE 0.0s

  #3 [internal] load metadata for <http://docker.io/containers/common:python-3-11-basic|docker.io/containers/common:python-3-11-basic>
  #3 ERROR: pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed
  ------
   > [internal] load metadata for <http://docker.io/containers/common:python-3-11-basic|docker.io/containers/common:python-3-11-basic>:
  ------
  Dockerfile:2
  --------------------
     1 |     ARG BASE_IMAGE
     2 | >>> FROM $BASE_IMAGE
     3 |
     4 |     RUN apt update && apt install -y \
  --------------------
  ERROR: failed to solve: containers/common:python-3-11-basic: pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed



  Use `--keep-sandboxes=on_failure` to preserve the process chroot for inspection.

======= containers/sample:sample-other-pants-tgt-parametrized-image-absolute-via-build_args
  08:11:12.22 [INFO] Starting: Building docker image python:3.11-slim
  08:11:13.82 [INFO] Completed: Building docker image python:3.11-slim
  08:11:13.83 [INFO] Starting: Building docker image sample-other-pants-tgt-parametrized-image-absolute-via-build_args:latest
  08:11:13.93 [INFO] Completed: Building docker image sample-other-pants-tgt-parametrized-image-absolute-via-build_args:latest
  08:11:13.94 [WARN] Docker build failed for `docker_image` containers/sample:sample-other-pants-tgt-parametrized-image-absolute-via-build_args. There are files in the Docker build context that were not referenced by any `COPY` instruction (this is not an error):

    * containers.common/images-python@parametrize=py311deb.docker-info.json
    * my_simple_lib-4.3.1-py3-none-any.whl
    * my_simple_lib-4.3.1.tar.gz


  08:11:13.94 [ERROR] 1 Exception encountered:

  Engine traceback:
    in `package` goal

  ProcessExecutionFailure: Process 'Building docker image sample-other-pants-tgt-parametrized-image-absolute-via-build_args:latest' failed with exit code 1.
  stdout:

  stderr:
  #0 building with "default" instance using docker driver

  #1 [internal] load .dockerignore
  #1 transferring context: 2B done
  #1 DONE 0.0s

  #2 [internal] load build definition from Dockerfile
  #2 transferring dockerfile: 115B done
  #2 DONE 0.0s
  Dockerfile:2
  --------------------
     1 |     ARG BASE_IMAGE
     2 | >>> FROM $BASE_IMAGE
     3 |
     4 |     RUN apt update && apt install -y \
  --------------------
  ERROR: failed to solve: failed to parse stage name "//containers/common:images-python@parametrize=py311deb": invalid reference format



  Use `--keep-sandboxes=on_failure` to preserve the process chroot for inspection.

======= containers/sample:sample-other-pants-tgt-parametrized-image-relative-via-build_args
  08:11:20.97 [INFO] Starting: Building docker image python:3.11-slim
  08:11:22.59 [INFO] Completed: Building docker image python:3.11-slim
  08:11:22.59 [INFO] Starting: Building docker image sample-other-pants-tgt-parametrized-image-relative-via-build_args:latest
  08:11:22.70 [INFO] Completed: Building docker image sample-other-pants-tgt-parametrized-image-relative-via-build_args:latest
  08:11:22.70 [WARN] Docker build failed for `docker_image` containers/sample:sample-other-pants-tgt-parametrized-image-relative-via-build_args. There are files in the Docker build context that were not referenced by any `COPY` instruction (this is not an error):

    * containers.common/images-python@parametrize=py311deb.docker-info.json
    * my_simple_lib-4.3.1-py3-none-any.whl
    * my_simple_lib-4.3.1.tar.gz


  08:11:22.70 [ERROR] 1 Exception encountered:

  Engine traceback:
    in `package` goal

  ProcessExecutionFailure: Process 'Building docker image sample-other-pants-tgt-parametrized-image-relative-via-build_args:latest' failed with exit code 1.
  stdout:

  stderr:
  #0 building with "default" instance using docker driver

  #1 [internal] load .dockerignore
  #1 transferring context: 2B done
  #1 DONE 0.0s

  #2 [internal] load build definition from Dockerfile
  #2 transferring dockerfile: 115B done
  #2 DONE 0.0s
  Dockerfile:2
  --------------------
     1 |     ARG BASE_IMAGE
     2 | >>> FROM $BASE_IMAGE
     3 |
     4 |     RUN apt update && apt install -y \
  --------------------
  ERROR: failed to solve: failed to parse stage name "containers/common:images-python@parametrize=py311deb": invalid reference format



  Use `--keep-sandboxes=on_failure` to preserve the process chroot for inspection.

======= containers/sample:sample-other-pants-tgt-parametrized-image-via-static_in_dockerfile
  08:11:29.59 [INFO] Starting: Building docker image python:3.11-slim
  08:11:31.23 [INFO] Completed: Building docker image python:3.11-slim
  08:11:31.24 [INFO] Starting: Building docker image sample-other-pants-tgt-parametrized-image-via-static_in_dockerfile:latest
  08:11:35.83 [INFO] Completed: Building docker image sample-other-pants-tgt-parametrized-image-via-static_in_dockerfile:latest
  08:11:35.83 [INFO] Wrote dist/containers.sample/sample-other-pants-tgt-parametrized-image-via-static_in_dockerfile.docker-info.json
  Built docker image: sample-other-pants-tgt-parametrized-image-via-static_in_dockerfile:latest
  Docker image ID: sha256:a0c60e6f2e41b60d445837ee76b5cc993f90d7097b302b517d3632d834f06aad

without looking at the code, my summary is that pants docker inference support is only happening on the Dockerfile, not on the build_args going in.

in "logical pseudo code" • It appears like pants does -

sed -i s/pants_tgt_address/pants_image_sha_pre-built/g Dockerfile

• and not

cat $pants_docker_cmd_line_args | sed s/pants_tgt_address/pants_image_sha_pre-built/g

But, I see how this could be useful, so will ponder a bit at how difficult it would be to support.. 🙂