The Dockerfile is a recipe for how to build the container image, while .dockerignore defines the set of files that should be ignored when copying files into the image.

# Start from a Node.js 16 (LTS) image 1
FROM node:16

# Specify the directory inside the image in which all commands will run 2
WORKDIR /usr/src/app

# Copy package files and install dependencies 3
COPY package*.json ./
RUN npm install
RUN npm install express

# Copy all of the app files into the image 4
COPY . .

# The default command to run when starting the container 5
CMD [ "npm", "start" ]

FROM golang:1.17-alpine

# Install Node and NPM
RUN apk update && apk upgrade && apk add --no-cache git nodejs bash npm

# Get dependencies for Go part of build
RUN go get -u github.com/jteeuwen/go-bindata/...
RUN go get github.com/tools/godep
RUN go get github.com/kubernetes-up-and-running/kuard

WORKDIR /go/src/github.com/kubernetes-up-and-running/kuard

# Copy all sources in
COPY . .

# This is a set of variables that the build script expects
ENV VERBOSE=0
ENV PKG=github.com/kubernetes-up-and-running/kuard
ENV ARCH=amd64
ENV VERSION=test

# Do the build. This script is part of incoming sources.
RUN build/build.sh

CMD [ "/go/bin/kuard" ]

Multistage Dockerfile:

# STAGE 1: Build
FROM golang:1.17-alpine AS build

# Install Node and NPM
RUN apk update && apk upgrade && apk add --no-cache git nodejs bash npm

# Get dependencies for Go part of build
RUN go get -u github.com/jteeuwen/go-bindata/...
RUN go get github.com/tools/godep

WORKDIR /go/src/github.com/kubernetes-up-and-running/kuard

# Copy all sources in
COPY . .

# This is a set of variables that the build script expects
ENV VERBOSE=0
ENV PKG=github.com/kubernetes-up-and-running/kuard
ENV ARCH=amd64
ENV VERSION=test

# Do the build. Script is part of incoming sources.
RUN build/build.sh

# STAGE 2: Deployment
FROM alpine

USER nobody:nobody
COPY --from=build /go/bin/kuard /kuard

CMD [ "/kuard" ]