FROM node:12-alpine * to be based on which other Docker image?
RUN apk add --no-cache python g++ make * install additional software
WORKDIR /app * create and use directory /app inside the container
COPY . . * 1st parameter: local directory (./ is the directory where the Dockerfile is) * 2nd parameter: target directory inside the container * → copy everything where the Dockerfile is in, into the container under /app
RUN npm install * dependencies for the application
CMD ["node", "src/index.js"] * run the app - just like when running outside a container
Video: Dockerfile Theory
Video: Dockerfile Practice