chore: docker image based on distroless & build and docker scripts

[carlocorradini]

Related to PR #671

What has been changed:

• rumqttd Docker image is based on distroless rather than Alpine
  Docker image is now based on gcr.io/distroless/cc (from Google) to enhance overall security since "it does not contain package managers, shells or any other programs you would expect to find in a standard Linux distribution"

• More robust and fully configurable scripts (see scripts and rumqttd/scripts directories). Also POSIX compliant

  1. rumqttd/scripts/docker.sh
     Build and push rumqttd Docker image
  2. rumqttd/scripts/build.sh
     Build rumqttd using Cross

  Note that both scripts are configurable and also have an helper flag (--help)

[carlocorradini]

@de-sh Any update? 🤗🥳

[carlocorradini]

@swanandx @henil Any thoughts on this? I apologize for pinging

[h3nill]

i think the script is very complicated and i am not sure that its really necessary. and for distroless docker image what are the advantage to use those instead of what we have currently?

[carlocorradini]

I believe the numerous papers on Distroless vs Alpine can explain it far better than I can.😂😅
See this or this or ...

[carlocorradini]

These scripts are quite user-friendly (with --help and args configuration) and POSIX compliant

[carlocorradini]

The main parts are a few lines of code:

build.sh

docker.sh

Easy peasy