Staged Docker builds for dev and prod

frontend/Dockerfile

@@ -1,9 +1,22 @@
-FROM node:16-alpine
+FROM node AS dev
 
 WORKDIR /app
 EXPOSE 8080
-CMD ["npm", "run", "dev"]
 
 COPY package* ./
 RUN npm install
 COPY . .
+
+ENTRYPOINT ["npm", "run", "dev"]
+
+# builder
+FROM dev AS builder
+RUN npm run build
+
+# serve
+FROM nginx AS prod
+WORKDIR /usr/share/nginx/html
+RUN rm -rf ./*
+COPY ./nginx.conf /etc/nginx/conf.d/default.conf
+COPY --from=builder /app/dist .
+ENTRYPOINT ["nginx", "-g", "daemon off;"]