install node 12.x docker code example

Example 1: docker node alpine

# Copy and paste to pull this image for the latest 
docker pull node

# more specific use this line
# docker pull node:<version>-alpine 
docker pull node:14.4-alpine3.11

Example 2: nodejs docker

FROM node:boron

RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app

COPY package.json /usr/src/app/
RUN npm install

COPY . /usr/src/app

EXPOSE 3000

CMD ["npm","start"]