Dockerfile

FROM node:latest

WORKDIR /app

COPY package*.json ./
RUN npm install


# Accept build-time public env vars as build args
ARG NEXT_PUBLIC_FIREBASE_API_KEY
ARG NEXT_PUBLIC_FIREBASE_AUTH_DOMAIN
ARG NEXT_PUBLIC_FIREBASE_PROJECT_ID
ARG NEXT_PUBLIC_FIREBASE_STORAGE_BUCKET
ARG NEXT_PUBLIC_FIREBASE_MESSAGING_SENDER_ID
ARG NEXT_PUBLIC_FIREBASE_APP_ID
ARG NEXT_PUBLIC_FIREBASE_MEASUREMENT_ID

# Set them as env for build step
ENV NEXT_PUBLIC_FIREBASE_API_KEY=$NEXT_PUBLIC_FIREBASE_API_KEY
ENV NEXT_PUBLIC_FIREBASE_AUTH_DOMAIN=$NEXT_PUBLIC_FIREBASE_AUTH_DOMAIN
ENV NEXT_PUBLIC_FIREBASE_PROJECT_ID=$NEXT_PUBLIC_FIREBASE_PROJECT_ID
ENV NEXT_PUBLIC_FIREBASE_STORAGE_BUCKET=$NEXT_PUBLIC_FIREBASE_STORAGE_BUCKET
ENV NEXT_PUBLIC_FIREBASE_MESSAGING_SENDER_ID=$NEXT_PUBLIC_FIREBASE_MESSAGING_SENDER_ID
ENV NEXT_PUBLIC_FIREBASE_APP_ID=$NEXT_PUBLIC_FIREBASE_APP_ID
ENV NEXT_PUBLIC_FIREBASE_MEASUREMENT_ID=$NEXT_PUBLIC_FIREBASE_MEASUREMENT_ID

COPY . .
RUN npm run build

EXPOSE 3000

# Only set NODE_ENV at runtime; all other envs injected by Cloud Run
ENV NODE_ENV=production

CMD ["npm", "start"]