SvelteKit Dockerfile

# ============================================================================
# Created by https://Dockerfile.io/
# COMPREHENSIVE FRAMEWORK TEMPLATE for SvelteKit
# Website: https://kit.svelte.dev/
# Repository: https://github.com/sveltejs/kit
# ============================================================================

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# TEMPLATE OVERVIEW & USAGE NOTES
# ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
# • TEMPLATE TYPE: COMPREHENSIVE FRAMEWORK TEMPLATE
# • PURPOSE: Production-ready SvelteKit application with security hardening
# • DESIGN PHILOSOPHY: Self-contained with multi-stage builds and security
# • COMBINATION GUIDANCE: Use standalone for complete SvelteKit applications
# • SECURITY CONSIDERATIONS: Non-root user, Alpine base, health monitoring
# • BEST PRACTICES: Layer caching, dependency optimization, production defaults
# • OFFICIAL SOURCES: SvelteKit documentation and Docker security guidelines

# ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
# BUILDER STAGE - Application compilation
# ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
FROM node:18-alpine AS builder

# Build arguments for environment configuration
ARG NODE_ENV=production
ARG BUILD_ID=unknown
ARG COMMIT_SHA=unknown
ARG ORIGIN=https://localhost:3000

# Environment variables for build process
ENV NODE_ENV=${NODE_ENV} \
  BUILD_ID=${BUILD_ID} \
  COMMIT_SHA=${COMMIT_SHA} \
  ORIGIN=${ORIGIN} \
  npm_config_update_notifier=false \
  npm_config_cache=/tmp/.npm

# Set working directory
WORKDIR /app

# Copy dependency files first for optimal layer caching
COPY package*.json ./
COPY pnpm-lock.yaml* ./
COPY yarn.lock* ./

# Install dependencies based on package manager
RUN if [ -f "pnpm-lock.yaml" ]; then \
      npm install -g pnpm && \
      pnpm install --frozen-lockfile --prod; \
    elif [ -f "yarn.lock" ]; then \
      npm install -g yarn && \
      yarn install --frozen-lockfile --production; \
    else \
      npm install --omit=dev; \
    fi && \
    npm cache clean --force && \
    rm -rf /tmp/.npm

# Copy application source code
COPY . .

# Build SvelteKit application
RUN if [ -f "pnpm-lock.yaml" ]; then \
      pnpm run build; \
    elif [ -f "yarn.lock" ]; then \
      yarn run build; \
    else \
      npm run build; \
    fi

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# RUNTIME STAGE - Production deployment
# ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
FROM node:18-alpine AS runtime

# Security: Use built-in non-root node user
USER node

# Production environment configuration
ENV NODE_ENV=production \
  ORIGIN=https://localhost:3000 \
  npm_config_update_notifier=false \
  UMASK=0027

# Set working directory
WORKDIR /app

# Copy built artifacts from builder stage with proper ownership
COPY --from=builder --chown=node:node /app/package*.json ./
COPY --from=builder --chown=node:node /app/node_modules ./node_modules
COPY --from=builder --chown=node:node /app/build ./build
COPY --from=builder --chown=node:node /app/static ./static

# Create directories with secure permissions
RUN mkdir -p /app/logs /app/tmp && \
  chown -R node:node /app/logs /app/tmp && \
  chmod 750 /app/logs /app/tmp

# Expose application port (default SvelteKit server port)
EXPOSE 3000

# Health check for container orchestration
HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
  CMD node -e "require('http').get('http://localhost:3000', (r) => { \
  process.exit(r.statusCode === 200 ? 0 : 1); \
  }).on('error', () => process.exit(1))"

# Start SvelteKit production server
ENTRYPOINT ["node", "build/index.js"]

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# DEVELOPMENT STAGE - Hot reload environment
# ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
FROM node:18-alpine AS development

WORKDIR /app

# Copy dependency files
COPY package*.json ./
COPY pnpm-lock.yaml* ./
COPY yarn.lock* ./

# Install all dependencies (including dev dependencies)
RUN if [ -f "pnpm-lock.yaml" ]; then \
      npm install -g pnpm && \
      pnpm install --frozen-lockfile; \
    elif [ -f "yarn.lock" ]; then \
      npm install -g yarn && \
      yarn install --frozen-lockfile; \
    else \
      npm ci; \
    fi

# Copy source code
COPY . .

# Development command with hot reload
CMD if [ -f "pnpm-lock.yaml" ]; then \
      pnpm run dev; \
    elif [ -f "yarn.lock" ]; then \
      yarn run dev; \
    else \
      npm run dev; \
    fi

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# USAGE EXAMPLES & BEST PRACTICES
# ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

# Example 1: Build production image
# docker build --target runtime -t my-sveltekit-app:prod .

# Example 2: Build development image
# docker build --target development -t my-sveltekit-app:dev .

# Example 3: Build with custom arguments
# docker build \
#   --build-arg NODE_ENV=production \
#   --build-arg BUILD_ID=$(git rev-parse --short HEAD) \
#   --build-arg ORIGIN=https://example.com \
#   -t my-sveltekit-app:$(git rev-parse --short HEAD) .

# Example 4: Run production container
# docker run -d -p 3000:3000 --name sveltekit-app my-sveltekit-app:prod

# Example 5: Run development container
# docker run -d -p 3000:3000 -v $(pwd):/app --name sveltekit-dev my-sveltekit-app:dev

# Example 6: Build with adapter-specific configuration
# docker build \
#   --build-arg ADAPTER=node \
#   -t my-sveltekit-app:node .

# Best Practices:
# 1. Always use .dockerignore to exclude node_modules, .git, build, etc.
# 2. Use specific Node.js versions (not 'latest')
# 3. Run health checks in production
# 4. Use multi-stage builds for smaller images
# 5. Set resource limits in docker-compose or Kubernetes

# Customization Notes:
# 1. Adjust exposed ports based on your SvelteKit configuration
# 2. Modify health check endpoint as needed
# 3. Add environment variables for your application
# 4. Customize build commands for your SvelteKit setup
# 5. Consider using different adapters (node, static, vercel, etc.)

# SvelteKit Adapter Support:
# This template supports all SvelteKit adapters. For adapter-specific configurations:
# 1. Node adapter: Uses the runtime stage above
# 2. Static adapter: Builds to static files served by npx serve
# 3. Vercel/Netlify adapters: May require additional runtime configuration

# Package Manager Support:
# This template automatically detects and uses:
# - npm (default)
# - yarn (if yarn.lock exists)
# - pnpm (if pnpm-lock.yaml exists)

# Adapter Configuration:
# The template uses the default Node adapter.
# To use a different adapter, install and configure it in your SvelteKit project.

# SSR vs Static Generation:
# For static generation, use SvelteKit's static adapter and serve static files.
# For SSR, use the Node adapter as configured above.

# Environment Variables:
# SvelteKit uses Vite for environment variables. Prefix public variables with PUBLIC_
# Private variables should be set at runtime or through build arguments.