Make it compatible with docker compose 2.x

[aminvakil]

Description

docker compose 2.x complains with this error: "key cannot contain a space" or

unexpected character "(" in variable name near "whitelist host after N successful deliveries (N=0 to disable whitelisting)\nPOSTGREY_AUTO_WHITELIST_CLIENTS=5\n\n#

when POSTGREY_TEXT value is something with spaces.

Type of change

• Improvement (non-breaking change that does improve existing functionality)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (README.md or the documentation under docs/)
• If necessary I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[georglauterbach]

Hey @aminvakil, thanks for providing a PR :) We aim to maintain DMS for Docker Compose version 3. Therefore, I'm not sure whether we want to have compatibility fixes with Compose version 2. @casperklein @wernerfred your opinion on this?

[aminvakil]

I'm not sure if I was clear enough or I'm misunderstanding :)

I'm talking about https://github.com/docker/compose/releases/tag/v2.0.1 which has just been released.

[casperklein]

I had also issues with the latest docker-compose 2 version and some compose files, but no time yet to take a deeper look.

If white spaces are an issue, we should quote them.

[aminvakil]

If white spaces are an issue, we should quote them.

Thanks, this is definitely a better approach, changed.

[casperklein]

The quotes must surround the whole string. Otherwise, the quotes are part of the variable value.

Edit:

https://docs.docker.com/compose/compose-file/compose-file-v3/#env_file

For example if the value is surrounded by quotes (as is often the case of shell variables), the quotes are included in the value passed to Compose.

[georglauterbach]

I didn't even know about this - feels like ages since I left Compose :D Nice!

[casperklein]

Damn. I've mistaken it.

You need to surround the whole env string when set directly in docker-compose.yml. However, not when using an extra env_file 😞

[georglauterbach]

@casperklein just provide a follow up PR:)

[casperklein]

That's weird. I will take a deeper look later.

The documentation says, to quote the whole string, even in an env_file. In my test with docker-compose 1.29.2 however, the var is completely ignored, when fully quoted in an env_file.

Two possibilities:

1. This is a breaking change between the docker-compose versions
2. The documentation is wrong.