Dockerfile

# Multi-stage build for optimal image size
FROM python:3.12-slim as builder

# Set environment variables for Poetry
ENV POETRY_NO_INTERACTION=1 \
    POETRY_VENV_IN_PROJECT=1 \
    POETRY_CACHE_DIR=/tmp/poetry_cache \
    POETRY_HOME="/opt/poetry" \
    POETRY_VERSION=1.8.3

# Install system dependencies needed for building
RUN apt-get update && apt-get install -y \
    build-essential \
    curl \
    libpq-dev \
    && rm -rf /var/lib/apt/lists/*

# Install Poetry
RUN pip install poetry==$POETRY_VERSION

# Set working directory
WORKDIR /app

# Copy Poetry configuration files first (better layer caching)
COPY pyproject.toml poetry.lock ./

# Configure Poetry and install only production dependencies
RUN poetry config virtualenvs.create false \
    && poetry install --only=main --no-root \
    && rm -rf $POETRY_CACHE_DIR

# Production stage
FROM python:3.12-slim as production

# Set environment variables
ENV PYTHONUNBUFFERED=1 \
    PYTHONDONTWRITEBYTECODE=1

# Install only runtime dependencies
RUN apt-get update && apt-get install -y \
    libpq5 \
    && rm -rf /var/lib/apt/lists/*

# Create non-root user for security
RUN groupadd -r appuser && useradd -r -g appuser appuser

# Set working directory
WORKDIR /app

# Copy installed packages from builder stage
COPY --from=builder /usr/local/lib/python3.12/site-packages /usr/local/lib/python3.12/site-packages
COPY --from=builder /usr/local/bin /usr/local/bin

# Copy application code (exclude unnecessary files via .dockerignore)
COPY . .

# Install the application using Poetry's project definition
RUN pip install -e . --no-deps

# Change ownership to non-root user
RUN chown -R appuser:appuser /app

# Switch to non-root user
USER appuser

# Expose port
EXPOSE 8080

# Add health check (requires adding health endpoint to your app)
HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
    CMD python -c "import httpx; httpx.get('http://localhost:8080/health', timeout=5)" || exit 1

# Run the application
CMD ["python", "-m", "app"]