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First we had a docker layer with following `Dockerfile`.

FROM node:12-alpine

# Create app directory
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app

# Install system requirements
RUN apk update && apk add --no-cache --virtual .build-deps make gcc g++ python \
  && rm -rf node_modules \
  && apk add git \
  && apk del .build-deps

# ENV
ENV NODE_ENV=production

# Install app dependencies
COPY package.json /usr/src/app/
COPY yarn.lock /usr/src/app/
RUN yarn install

# Bundle app source
COPY . /usr/src/app
RUN yarn generate

# Clear the cache
RUN yarn cache clean

ENV HOST 0.0.0.0
EXPOSE 3000

CMD ["yarn", "start" ]

This setup had a size of 853 MB.

My WiFi was over and I was allowed to hit 512 KB max.

So I had to reduce the size as I needed to constantly push this image for an on premise solution.

After some minor research I found that multi-stage builds do help.

So here my updated Dockerfile.

FROM node:12-alpine AS build

# Create app directory
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app

# Install system requirements
RUN apk update && apk add --no-cache --virtual .build-deps make gcc g++ python \
  && rm -rf node_modules \
  && apk add git \
  && apk del .build-deps

# ENV
ENV NODE_ENV=production

# Install app dependencies
COPY package.json /usr/src/app/
COPY yarn.lock /usr/src/app/
RUN yarn install

# Bundle app source
COPY . /usr/src/app
RUN yarn generate

# Clear the cache
RUN yarn cache clean


FROM gcr.io/distroless/nodejs
COPY --from=build /usr/src/app /usr/src/app
WORKDIR /usr/src/app
ENV HOST 0.0.0.0
EXPOSE 3000

CMD ["standalone.js" ]

The distroless idea I got from the referred article (link below).

Now my docker image has final size of 409 MB. A massive decrease in size at first go.

I will look into reducing it more when I get time. 😉

Bonus: Content of standalone.js for all Nuxt.js developers.

require('child_process').fork('node_modules/nuxt/bin/nuxt.js', ['start'])

Ref: Why You Should Use Multi-Stage Docker Builds in Production | by Bryant Hagadorn | ITNEXT