Is it possible to have multiple docker-volume-backup.stop-during-backup=labelX?

[huyz]

If I have a list of labels like docker-volume-backup.stop-during-backup=label1 and docker-volume-backup.stop-during-backup=label2, would either label cause the container to stop. I'm not sure how valid it is to have labels with the same key

[m90]

Docker won't let you apply the same label twice without overriding the previous value:

The key=value must be unique to avoid overwriting the label value. If you specify labels with identical keys but different values, each subsequent value overwrites the previous. Docker uses the last key=value you supply.

I do like the possible feature though, but I'm not sure about how to implement it. Firstly, I'll have to play the same old record again: starting to split the values on commas would make sense, but is a breaking change, so that's not what to do.

How it could be done:

• come up with a good new label name whose value is being split on commas automatically
• keep the old behavior for the old label name, but print a deprecation warning on usage
• remove all mentions of the old label from the docs
• on the next major version, remove the old label entirely

I'll give this some time to roam around in the back of my head still.

[m90]

I created an issue here #621