FROM python:3.12-slim
ENV PYTHONDONTWRITEBYTECODE=1 \
    PYTHONUNBUFFERED=1 \
    PORT=8000 \
    DATA_DIR=/app/data
WORKDIR /app
RUN apt-get update \
    && apt-get install -y --no-install-recommends tzdata \
    && rm -rf /var/lib/apt/lists/*
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt
COPY . .
RUN mkdir -p /app/data/instance /app/data/exams
EXPOSE 8000
CMD ["gunicorn", "--config", "gunicorn.conf.py", "app:app"]