Dockerfile

# Multi-stage Docker build for FastAPI microservice
# Demonstrates production-ready containerization patterns

FROM python:3.11-slim as base

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

# Create non-root user for security
RUN groupadd --gid 1000 appuser && \
    useradd --uid 1000 --gid 1000 --create-home --shell /bin/bash appuser

# Install system dependencies
RUN apt-get update && apt-get install -y --no-install-recommends \
    build-essential \
    curl \
    && rm -rf /var/lib/apt/lists/*

# Development stage
FROM base as development

WORKDIR /app

# Install Python dependencies
COPY requirements.txt .
RUN pip install --no-deps -r requirements.txt

# Copy application code
COPY . .

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

# Switch to non-root user
USER appuser

# Expose port
EXPOSE 8000

# Development command with hot reload
CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8000", "--reload"]

# Production stage
FROM base as production

WORKDIR /app

# Install only production dependencies
COPY requirements.txt .
RUN pip install --no-deps -r requirements.txt && \
    pip cache purge

# Copy application code
COPY --chown=appuser:appuser . .

# Switch to non-root user
USER appuser

# Health check
HEALTHCHECK --interval=30s --timeout=30s --start-period=5s --retries=3 \
    CMD curl -f http://localhost:8000/health/live || exit 1

# Expose port
EXPOSE 8000

# Production command
CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8000", "--workers", "4"]