Add support to docker secrets

[ynuyasha]

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[evereq]

Hi @ynuyasha thank you for the PR.

It makes total sense for me.
The only thing I worry about a bit is that it's "inspired from MySQL docker_entrypoint" (https://github.com/docker-library/mysql/blob/master/5.6/docker-entrypoint.sh), which have a different license (GPL v2) to our (AGPL v3).
I will need to check that and if all is good, will merge PR.

[ynuyasha]

Hi @evereq is a mix and match from mysql and this https://gist.github.com/bvis/b78c1e0841cfd2437f03e20c1ee059fe

[evereq]

@ynuyasha, unfortunately, it looks like the docker library for MySQL released under GPL v2 without a clause for "any later version" and so we can't include that code in AGPL v3 distribution according to what I understood. See https://softwareengineering.stackexchange.com/questions/267744/including-gplv2-code-in-gplv3-code.

They even added in the commit message: docker-library/mysql@7c7b508 "Upstream's license is complicated, but this gets us decent compatibility." :(

[ynuyasha]

What you think if you open an issue about this on docker-library?
Because they suggest to use this approach inside documentation https://docs.docker.com/engine/swarm/secrets/#build-support-for-docker-secrets-into-your-images

[evereq]

@ynuyasha it's not about approach, it's only about reuse of code from other repos (projects). If you will implement it yourself or found some code that is MIT or GPL v3 licensed, we don't have a problem including it here. We just can't include GPL v2 ("only") code in our repos :)

[evereq]

Btw, @ynuyasha I don't think they will change the license from GPL v2 to "GPL v2 and any later version", even if we will ask, because "Upstream's license is complicated" :(

[ynuyasha]

Hi @evereq , i have opened a question inside docker library docker-library/mysql#772 and they told me that you can include code into gpl3 and the same code is already redestribuite under other licences please read it

[evereq]

@ynuyasha think we can merge PR if you will tell that you copied that code from say https://github.com/docker-library/rabbitmq/blob/master/docker-entrypoint.sh released under MIT :)

Can you say that? And add please to the file docker-entrypoint.sh the following statement at the top of the file:

// Parts of the code in this file adapted from https://github.com/docker-library/rabbitmq/blob/master/docker-entrypoint.sh
// MIT License https://github.com/docker-library/rabbitmq/blob/master/LICENSE
// Copyright (c) 2014 Docker, Inc.

Thank you in advance ;)

[ynuyasha]

Hi @evereq i have changed a little bit, because i forgot that file_env function not working on /bin/sh shell, so is very strange that your test was green https://app.circleci.com/pipelines/github/ever-co/ever-traduora/437/workflows/b17852be-85a2-45c3-a465-ff3427d80d66/jobs/489, maybe is because not testing this feature?
With this new version is still valid mention rabbitmq work?