Basic NextJS Dockerfile

NextJS.Dockerfile

# Install dependencies only when needed
FROM node:lts-alpine AS deps

WORKDIR /opt/app
COPY package.json yarn.lock ./
RUN yarn install --frozen-lockfile

# Rebuild the source code only when needed
# This is where because may be the case that you would try
# to build the app based on some `X_TAG` in my case (Git commit hash)
# but the code hasn't changed.
FROM node:lts-alpine

RUN mkdir -p /usr/src/app
ENV PORT 3000

WORKDIR /usr/src/app

COPY package.json /usr/src/app
COPY yarn.lock /usr/src/app

# Production use node instead of root
# USER node

RUN yarn install --production

COPY . /usr/src/app

RUN yarn build

EXPOSE 3000
CMD [ "yarn", "start" ]