In Dockerfile, we can separate the workflow and virtual memory space in the container using multi-step builds. Multi-step builds use the FROM and AS keywords to specify and generate a new step and workspace that is isolated from the other stages.
It can help us build a smaller final image by leaving dependencies in intermediate steps. It can also increase security and optimize build performance.
FROM node:20-alpine AS builder
WORKDIR /app
COPY package.json .
RUN npm install
COPY . .
RUN npm run build
FROM nginx:stable-alpine AS runner
COPY --from=builder /app/dist /usr/share/nginx/html
EXPOSE 80The example above shows a multi-stage build with two stages: builder and runner. In the builder stage, we use Node.js alpine as the base image to install and build the application.
This is followed by the runner stage, where we use another image nginx to build the nginx server, copy the built application from /app/dist of the builder stage to /usr/share/nginx/html of the runner stage, and expose port 80 for the nginx server.
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