Image Size ও Build Optimization

node_modules
.next
dist
.git
.env
.env.*
*.log
Dockerfile
.dockerignore
README.md

# ভুল — কোড আগে → প্রতি build-এ install আবার
COPY . .
RUN npm ci

# সঠিক — dependency স্থিতিশীল, পরে code
COPY package*.json ./
RUN npm ci
COPY . .

FROM node:20-alpine          # ~50MB
# vs node:20 (800MB+), node:20-slim (~250MB)
# distroless: শুধু runtime

# builder
FROM node:20-alpine AS builder
...
RUN npm ci && npm run build

# runtime — devDependencies ছাড়া
FROM node:20-alpine
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/dist ./dist

# BuildKit default (Docker 23+) — parallel stage, mount cache
DOCKER_BUILDKIT=1 docker build -t my-api .

# registry cache — uniform across machines
docker build --cache-from type=registry,ref=my-api:cache .

RUN --mount=type=cache,target=/root/.npm \
    npm ci --omit=dev

docker image ls
docker history my-api
docker system df