Built Objects from Docker Build Don't Carry Over

[aidanngill]

My aim is to use pytest-celery for my tests for a Django project. The issue that I am facing is that a folder I create in my worker's Dockerfile is no longer present when the worker runs.

FROM python:3.12.4-bullseye AS builder

RUN pip install poetry==1.8.3

ENV POETRY_NO_INTERACTION=1 \
    POETRY_VIRTUALENVS_IN_PROJECT=1 \
    POETRY_VIRTUALENVS_CREATE=1 \
    POETRY_CACHE_DIR=/tmp/poetry_cache

WORKDIR /build

COPY pyproject.toml poetry.lock ./

RUN poetry install --without dev --no-root && rm -rf $POETRY_CACHE_DIR

# ---------------------------------------------------------------------------- #

FROM python:3.12.4-slim-bullseye AS runtime

# Create a user to run the worker
RUN adduser --disabled-password --gecos "" test_user

# Set arguments
ARG CELERY_LOG_LEVEL=INFO
ARG CELERY_WORKER_NAME=celery_dev_worker
ARG CELERY_WORKER_QUEUE=celery
ENV LOG_LEVEL=$CELERY_LOG_LEVEL
ENV WORKER_NAME=$CELERY_WORKER_NAME
ENV WORKER_QUEUE=$CELERY_WORKER_QUEUE
ENV DJANGO_SETTINGS_MODULE=pterodactyl_billing.settings.testing

EXPOSE 5678

# Install packages
RUN mkdir -p /build/.venv

ENV VIRTUAL_ENV=/build/.venv \
    PATH="/build/.venv/bin:$PATH"

COPY --from=builder ${VIRTUAL_ENV} ${VIRTUAL_ENV}

# Switch to the test_user
USER test_user

WORKDIR /app

# Start the celery worker
CMD celery -A pterodactyl_billing worker --loglevel=$LOG_LEVEL -n $WORKER_NAME@%h -Q $WORKER_QUEUE

In my Dockerfile I use Poetry to install my dependencies to /build, away from /app and /src as those are overwritten later when the container is created.

My goal is to then use this /build folder as a virtual environment for Celery to use. However, when I run pytest it crashes, stating that Django is not installed. To try and solve this I explicitly stated that the /build/.venv/bin/celery binary should be used, but this reveals that this path is completely absent from the image.

Is there something I'm missing about the way pytest-celery creates images? If I build the worker image myself and run bash on it the directory exists there.

My worker creation script is also shown below.

from typing import Any
import celery
import os
from typing import Any
import celery
from pytest_docker_tools import build
from pytest_docker_tools import container
from pytest_docker_tools import fxtr
from pytest_celery import CeleryWorkerContainer
from pytest_celery import defaults


class DjangoWorkerContainer(CeleryWorkerContainer):
    @property
    def client(self) -> Any:
        return self

    @classmethod
    def version(cls) -> str:
        return celery.__version__

    @classmethod
    def log_level(cls) -> str:
        return "INFO"

    @classmethod
    def worker_name(cls) -> str:
        return "django_tests_worker"

    @classmethod
    def worker_queue(cls) -> str:
        return "celery"


worker_image = build(
    path=".",
    tag="aidanngill/pbp-worker:latest",
    dockerfile="billing/tests/worker/Dockerfile",
    buildargs=DjangoWorkerContainer.buildargs(),
)


default_worker_container = container(
    image="{worker_image.id}",
    ports=fxtr("default_worker_ports"),
    environment=fxtr("default_worker_env"),
    network="{default_pytest_celery_network.name}",
    volumes={
        # Volume: Worker /app
        "{default_worker_volume.name}": defaults.DEFAULT_WORKER_VOLUME,
        # Mount: source
        os.path.abspath(os.getcwd()): {
            "bind": "/src",
            "mode": "rw",
        },
    },
    wrapper_class=DjangoWorkerContainer,
    timeout=15,
)

...and the error I'm facing when running pytest.

--------------------------------------------------------------------------------------------- Captured stdout setup ---------------------------------------------------------------------------------------------
Creating network pytest-782d00c2-2621-4f70-aa0c-3e774ccd5755
Waiting for container to be ready..........RabbitMQContainer::jolly_brahmagupta is ready.

Waiting for container to be ready.RedisContainer::silly_shaw is ready.

Creating volume pytest-d887b353-3ff8-498f-ac4f-6ed926a0f984
Waiting for container to be ready.Waiting for CeleryWorkerContainer::festive_leavitt to get ready..............................
Waiting for CeleryWorkerContainer::festive_leavitt to get ready..............................
Waiting for CeleryWorkerContainer::festive_leavitt to get ready..............................

------------------------------------------------------------------------------------------------ festive_leavitt ------------------------------------------------------------------------------------------------
Usage: celery [OPTIONS] COMMAND [ARGS]...
Try 'celery --help' for help.

Error: Invalid value for '-A' / '--app':
Unable to load celery application.
While trying to load the module app the following error occurred:
Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/celery/bin/celery.py", line 58, in convert
    return find_app(value)
  File "/usr/local/lib/python3.10/site-packages/celery/app/utils.py", line 383, in find_app
    sym = symbol_by_name(app, imp=imp)
  File "/usr/local/lib/python3.10/site-packages/kombu/utils/imports.py", line 59, in symbol_by_name
    module = imp(module_name, package=package, **kwargs)
  File "/usr/local/lib/python3.10/site-packages/celery/utils/imports.py", line 109, in import_from_cwd
    return imp(module, package=package)
  File "/usr/local/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 883, in exec_module
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "/app/app.py", line 13, in <module>
    from billing.tasks import *
  File "/app/billing/tasks.py", line 4, in <module>
    from django.conf import settings
ModuleNotFoundError: No module named 'django'

I also see here that it's using python3.10 instead of python3.12 which is built into the Dockerimage?

Any help is appreciated, thanks.