add option for custom-tag

[gonuke]

Here is a first attempt to add an option for a custom tag.

[Firehed]

Thanks @gonuke - I just got back from vacation and will check this out shortly. At a glance it looks reasonable!

[Firehed]

Build issues aside (e.g. #37), I believe this will try to add the new custom tag to both the server and test stages. That seems fine, but I wanted to verify that was the intended behavior.

[gonuke]

I think the build issues are because this comes from a public fork. They may work if you push this branch to your upstream repo.

[gonuke]

Build issues aside (e.g. #37), I believe this will try to add the new custom tag to both the server and test stages. That seems fine, but I wanted to verify that was the intended behavior.

To be honest, I didn't think through that difference - I just copied what was done for tagging latest. Happy to discuss the pros/cons of that choice.

[Firehed]

Makes sense! I took a brief attempt at the build thing earlier today, but it turned into a rabbit hole that I don't have time to pursue at the moment. I can try doing a build from the main repo and see if I can force it to run properly.

As for the end result - I don't have a strong feeling either way, as I've always done both testing and deployments from the full commit SHA and consequently haven't needed additional tags.

This change is probably the path of least resistance as far as implementation goes - so if it suits your needs, it should be good. Can you tell me more about your custom tag needs?

[gonuke]

We're still working through the subtleties of the use cases, but in the past we've had workflows that tag/push an image with a temporary tag, e.g. ci_testing, and then test that image outside of Docker, and then only change the tag once those tests pass.