core/Dockerfile

# syntax=docker/dockerfile:1
# Keep this syntax directive! It's used to enable Docker BuildKit

# Based on https://github.com/python-poetry/poetry/discussions/1879?sort=top#discussioncomment-216865

FROM python:alpine as python-base

    # python
ENV PYTHONUNBUFFERED=1 \
    # prevents python creating .pyc files
    PYTHONDONTWRITEBYTECODE=1 \
    \
    # pip
    PIP_DISABLE_PIP_VERSION_CHECK=on \
    PIP_DEFAULT_TIMEOUT=100 \
    \
    # poetry
    # https://python-poetry.org/docs/configuration/#using-environment-variables
    POETRY_VERSION=1.8.0 \
    # make poetry install to this location
    POETRY_HOME="/opt/poetry" \
    # make poetry create the virtual environment in the project's root
    # it gets named `.venv`
    POETRY_VIRTUALENVS_IN_PROJECT=true \
    # do not ask any interactive question
    POETRY_NO_INTERACTION=1 \
    \
    # paths
    # this is where our requirements + virtual environment will live
    PYSETUP_PATH="/opt/pysetup" \
    VENV_PATH="/opt/pysetup/.venv"


# prepend poetry and venv to path
ENV PATH="$POETRY_HOME/bin:$VENV_PATH/bin:$PATH"


################################
# BUILDER-BASE
# Used to build deps + create our virtual environment
################################
FROM python-base as builder

# Update package lists and install necessary dependencies
RUN apk update && \
    apk add --no-cache build-base icu-data-full curl python3-dev musl-dev postgresql-dev postgresql-client

# install poetry - respects $POETRY_VERSION & $POETRY_HOME
# The --mount will mount the buildx cache directory to where
# Poetry and Pip store their cache so that they can re-use it
RUN --mount=type=cache,target=/root/.cache \
    curl -sSL https://install.python-poetry.org | python3 -

# copy project requirement files here to ensure they will be cached.
WORKDIR $PYSETUP_PATH
COPY poetry.lock pyproject.toml ./

# install runtime deps - uses $POETRY_VIRTUALENVS_IN_PROJECT internally
RUN --mount=type=cache,target=/root/.cache \
    poetry install --without=dev


################################
# Final image used for runtime
################################
FROM python-base

COPY --from=builder $PYSETUP_PATH $PYSETUP_PATH
COPY ./app /app/

WORKDIR /app

# Expose the port
EXPOSE 8000

# Command to run the application
CMD ["python", "server.py"]