dockerfile basics

/home/pyratebeard/src/udemy/docker_mastery/dockerfile-sample-1

• 'recipe' for creating images
• use -f to specify dockerfile
• must include FROM line to start
  • to start with an empty container use FROM scratch
• each stanza is another layer in the cache
• point logs to /dev/{stdout,stderr}
• EXPOSE to open ports, still use -p
• CMD is required and is run when the container is launched
• WORKDIR better than using cd command

extending official samples

/home/pyratebeard/src/udemy/docker_mastery/dockerfile-sample-2

• inherit everything from FROM
  • used CMD from building image