[NIFI-5646] Dockerfile.alpine: Added.

[jpds]

This pull request adds a separate Dockerfile for an Alpine Linux based image.

This has a difference of ~0.4G compared to the normal Debian based image:

% docker images | grep nifi
nifi                             1.7.1-alpine         4f93b2311bdc        6 minutes ago       1.41GB
apache/nifi                      1.7.1                b5827934cd00        2 months ago        1.82GB

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[MikeThomsen]

There should also be a copy under dockermaven and the Maven build should be updated to have a profile for each that switches to using alpine.

[MikeThomsen]

Looks like we're moving in the right direction. Now we need some Maven profiles to do different builds.

[jpds]

@MikeThomsen Yes, I had a look at https://github.com/spotify/docker-maven-plugin when I had added the dockermaven image but I couldn't find a way from the documentation to give the plugin the different Dockerfile image (akin to the -f flag of docker build) (I'm not a Maven expert either).

An alternative would be to put the Dockerfiles into subdirectories if the above is a limitation in the plugin.

[MikeThomsen]

@apiri What do you think?

An alternative would be to put the Dockerfiles into subdirectories if the above is a limitation in the plugin.

I think a separate alpine build would be a nice thing to have.

[apiri]

@MikeThomsen We (certain folks on the PMC) have some good flexibility with performing releases to Docker Hub. I think the Alpine addition is certainly fine and the tagging makes sense. Likely don't need the full breadth of offerings that JDK has (https://hub.docker.com/r/library/openjdk/tags/) but establishing a similar taxonomy would be my preference. That, in conjunction with helper scripts, would allow us to a bit more seamlessly automate this process for those that have push access to the repositories.

[joewitt]

closing due to inactivity