chore: optimize docker image size < 500MB with multi-stage build

.dockerignore

@@ -0,0 +1,29 @@
+# Git
+.git
+.gitignore
+
+# Node
+node_modules
+npm-debug.log
+
+# Python
+venv
+__pycache__
+*.pyc
+*.pyo
+*.pyd
+
+# Next.js
+.next
+out
+
+# Docker
+Dockerfile
+.dockerignore
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Misc
+*.log

Dockerfile

@@ -1,58 +1,60 @@
+# --- Stage 1: Frontend Builder ---
+FROM node:18-alpine AS builder
+WORKDIR /app/frontend
+COPY frontend/package*.json ./
+# Install dependencies including devDependencies for build
+RUN npm install --legacy-peer-deps
+COPY frontend/ ./
+# Build with standalone output
+ENV NEXT_PUBLIC_API_URL="http://localhost:8000"
+RUN npm run build
+
+# --- Stage 2: Final Runtime Image ---
 FROM python:3.11-slim
 
-# Install Node.js and dependencies
+# Install system dependencies
 RUN apt-get update && apt-get install -y \
     curl \
     gnupg \
     ffmpeg \
     ca-certificates \
+    nodejs \
+    npm \
     && update-ca-certificates \
-    && curl -fsSL https://deb.nodesource.com/setup_18.x | bash - \
-    && apt-get install -y nodejs \
     && rm -rf /var/lib/apt/lists/*
 
 WORKDIR /app
 
-# --- Backend Setup ---
+# Backend Setup
 COPY backend/requirements.txt ./backend/requirements.txt
 RUN pip install --no-cache-dir -r backend/requirements.txt
 
-# --- Frontend Setup ---
-COPY frontend/package*.json ./frontend/
-WORKDIR /app/frontend
-# Install dependencies (ignoring peer deps conflicts)
-RUN npm install --legacy-peer-deps
+# Frontend Setup (Copy from Builder)
+# Copy the standalone server
+COPY --from=builder /app/frontend/.next/standalone /app/frontend
+# Copy static files (required for standalone)
+COPY --from=builder /app/frontend/.next/static /app/frontend/.next/static
+COPY --from=builder /app/frontend/public /app/frontend/public
 
-COPY frontend/ .
-# Build Next.js (with ignore-lint already set in next.config.mjs)
-# We set API URL to http://localhost:8000 because in this container strategy, 
-# the browser will access the backend directly.
-# Wait, for client-side fetches, "localhost" refers to the user's machine.
-# If we run this container on port 3000 and 8000, localhost:8000 works internally via Rewrites.
-# ENV NEXT_PUBLIC_API_URL="http://localhost:8000" Removed to use relative path proxying
-# Build Next.js
-ENV NEXTAUTH_URL=http://localhost:3000
-# Secret should be provided at runtime via docker run -e or docker-compose
-ARG NEXTAUTH_SECRET_ARG=default_dev_secret_change_in_production
-ENV NEXTAUTH_SECRET=${NEXTAUTH_SECRET_ARG}
-RUN npm run build
-
-# --- Final Setup ---
-WORKDIR /app
+# Copy Backend Code
 COPY backend/ ./backend/
 
-# Create a start script
-# We also implement a "seed data" check.
-# If the volume mount is empty (missing data.json), we copy from our backup.
+# Create start script
 RUN mkdir -p backend/data_seed && cp -r backend/data/* backend/data_seed/ || true
 
+# Set Environment Variables
+ENV NODE_ENV=production
+ENV PORT=3000
+ENV HOSTNAME="0.0.0.0"
+
+# Note: Standalone mode runs with 'node server.js'
 RUN echo '#!/bin/bash\n\
     if [ ! -f backend/data/data.json ]; then\n\
     echo "Data volume appears empty. Seeding with bundled data..."\n\
     cp -r backend/data_seed/* backend/data/\n\
     fi\n\
     uvicorn backend.main:app --host 0.0.0.0 --port 8000 &\n\
-    cd frontend && npm start -- -p 3000\n\
+    cd frontend && node server.js\n\
     ' > start.sh && chmod +x start.sh
 
 EXPOSE 3000 8000

frontend/next.config.mjs

@@ -1,7 +1,9 @@
 /** @type {import('next').NextConfig} */
 const nextConfig = {
+    // strict mode true is default but good to be explicit
     // strict mode true is default but good to be explicit
     reactStrictMode: true,
+    output: "standalone",
     eslint: {
         ignoreDuringBuilds: true,
     },