Multistage Dockerfile to export dependencies with poetry and install them with pip

Dockerfile

###########
# BUILDER #
###########
FROM python:3.10.8-slim AS builder

# Upgrade pip
RUN pip install --upgrade pip

# Install a specific poetry version, it can be useful to avoid breaking changes
RUN pip install poetry==1.8.3

# Set the workdir
WORKDIR /app

# Copy poetry.lock* in case it doesn't exist in the repo
COPY pyproject.toml ./poetry.lock* ./
# If you have youw own .whl linked inside the pyproject, put them inside this folder
COPY external_packages ./external_packages

# Create requirements.txt and let poetry solve the right versions.
# The "--only main" flag refers only to the main group and excludes all the others, so if you have a "dev" group in your
# pyproject.toml it will be ignored.
RUN poetry export -f requirements.txt --output requirements.txt --without-hashes --only main

###########
# RUNTIME #
###########
FROM python:3.10.8-slim AS runtime

WORKDIR /app

# Copy the external packages and the requirements.txt file from the builder stage
COPY --from=builder ./app/external_packages external_packages
COPY --from=builder ./app/requirements.txt requirements.txt

# Install the requirements
RUN pip install --no-cache-dir -r ./requirements.txt

# Copy the project
COPY . .

# Let's the fun begin :)
CMD ["./entrypoint.sh"]