Multi-Stage Docker Builds

FROM node:20
WORKDIR /app
COPY package*.json ./
RUN npm ci
COPY . .
RUN npm run build
# Image includes: node, npm, dev dependencies, source code, build tools
# Size: ~1.2 GB
EXPOSE 3000
CMD ["node", "dist/index.js"]

# Stage 1: Build
FROM node:20-slim AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci
COPY . .
RUN npm run build

# Stage 2: Production
FROM gcr.io/distroless/nodejs20-debian12
WORKDIR /app
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/package.json ./
# Image includes: only Node.js runtime, compiled code, prod dependencies
# Size: ~130 MB
EXPOSE 3000
CMD ["dist/index.js"]

# Stage 1: Dependencies
FROM node:20-slim AS deps
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production && cp -R node_modules prod_modules
RUN npm ci

# Stage 2: Build
FROM node:20-slim AS builder
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY . .
RUN npm run build

# Stage 3: Runtime
FROM gcr.io/distroless/nodejs20-debian12
WORKDIR /app
COPY --from=deps /app/prod_modules ./node_modules
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/package.json ./
EXPOSE 3000
CMD ["dist/index.js"]

FROM golang:1.22 AS builder
WORKDIR /app
COPY go.* ./
RUN go mod download
COPY . .
RUN CGO_ENABLED=0 GOOS=linux go build -o server .

FROM scratch
COPY --from=builder /app/server /server
COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
EXPOSE 8080
ENTRYPOINT ["/server"]
# Final image: ~15 MB

# syntax=docker/dockerfile:1
FROM node:20-slim AS builder
WORKDIR /app
COPY package*.json ./
RUN --mount=type=secret,id=npmrc,target=/root/.npmrc npm ci
COPY . .
RUN npm run build

docker build --secret id=npmrc,src=$HOME/.npmrc -t myapp .