FROM python:3.12-slim

WORKDIR /app
ENV PYTHONUNBUFFERED=1

# Create a dedicated non-root user and group to run the proxy.
RUN groupadd --system appuser && useradd --system --gid appuser appuser

COPY requirements.txt ./
RUN pip install --no-cache-dir -r requirements.txt

COPY --chown=appuser:appuser proxy_server.py ./

EXPOSE 110 25

USER appuser

CMD ["python", "proxy_server.py"]