Dockerfile

# ───────────────────────────────────────
# 🚀 1️⃣ Multi-Stage Build for Smallest Image
# ───────────────────────────────────────
FROM python:3.9-slim AS builder

# Set a fixed working directory
WORKDIR /app

# Install essential build tools
RUN apt-get update && apt-get install -y gcc g++ python3-dev libffi-dev && \
    python3 -m venv venv && \
    . venv/bin/activate && \
    pip install --no-cache-dir --upgrade pip setuptools wheel

# Copy only requirements first for better caching
COPY requirements.txt .
RUN apt-get install -y gfortran libopenblas-dev && \
    . venv/bin/activate && \
    pip install --no-cache-dir -r requirements.txt

# Copy the rest of the app files
COPY . .

# ───────────────────────────────────────
# 🚀 2️⃣ Runtime Image - Minimal & Secure
# ───────────────────────────────────────
FROM python:3.9-slim

# Set working directory
WORKDIR /app

# Copy virtual environment from builder stage
COPY --from=builder /app/venv /app/venv

# Environment Variables for Performance & Security
ENV PATH="/app/venv/bin:$PATH" \
    PYTHONUNBUFFERED=1 \
    PYTHONDONTWRITEBYTECODE=1 \
    APP_USER=appuser

# Security: Create and use non-root user
RUN addgroup appgroup && adduser appuser && \
    adduser appuser appgroup && \
    chown -R appuser:appgroup /app

USER $APP_USER

# Copy application code (Ensures proper permissions)
COPY --chown=$APP_USER:appgroup . .

# Debugging commands to check working directory and list files
RUN pwd && ls -l /app

# Use a health check to ensure the container is running correctly
HEALTHCHECK --interval=30s --timeout=10s --start-period=5s \
  CMD python3 -c 'import os; exit(0 if os.path.exists("summary.py") else 1)'

# Use ENTRYPOINT instead of CMD for better runtime control
ENTRYPOINT ["python3", "summary.py"]