[gerases]

docker ps only lists containers on this node, so a stack with replicas
elsewhere looked missing and was redeployed every agent run. exists? now
compares compose services to docker stack services, strips a Swarm
digest pin from the image name, and treats a failed stack query as
absent. Compose files are loaded with Puppet::Util::Yaml.safe_load and
version 3.8 is accepted.

Fixes #968
Fixes #973

Summary

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Additional Context

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• Root cause and the steps to reproduce. (If applicable)
• Thought process behind the implementation.

Related Issues (if any)

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Checklist

• 🟢 Spec tests.
• 🟢 Acceptance tests.
• Manually verified. (For example puppet apply)

[CLAassistant]

All committers have signed the CLA.

[gerases]

@skyamgarp, this fixes the docker_stack provider, would appreciate a review and if possible a merge.

[jst-cyr]

@gerases: It seems that there are some syntax issues found by the Rubocop testing:

• Spec Test Failure

Error: Style/BlockDelimiters: Prefer `do...end` for multi-line blocks without chaining. ([https://rubystyle.guide#single-line-blocks](https://rubystyle.guide/#single-line-blocks))
Error: Style/RegexpLiteral: Use `%r` around regular expression. ([https://rubystyle.guide#percent-r](https://rubystyle.guide/#percent-r))

[gerases]

@jst-cyr, let me know if anything else is needed. Thank you!

[jst-cyr]

@gerases : Thank you! Spec tests are passing, so I'll kick off some acceptance tests.

[jst-cyr]

Running CI tests for this PR here: #1073

[jst-cyr]

Acceptance Test Results: https://github.com/puppetlabs/puppetlabs-docker/actions/runs/34889231355?pr=1073

Mostly green, but failures on CentOS-7, CentOS-8, Debian-10, Debian-11, and Ubuntu-20.04. I have compared these failures and they match identically to the failures against main that we are seeing in the nightly acceptance tests. This PR does not seem to be introducing new failures.

This still requires an engineering review, but testing seems good!