test(framework): support running universal tests on remote host

[jijiechen]

Motivation

Support running universal tests on remote hosts

Implementation information

• support establishing SSH tunnels to remote hosts before executing commands
• introduce a new DockerBackend to encapsulate calls to docker commands: the local backend executes directly, the new remote backend executes commands via an SSH tunnel
• support forwarding local port to remote host within the SSH tunnel so kumactl is able to access the CP ports exposed from the container running on the remote host

[github-actions]

Reviewer Checklist

🔍 Each of these sections need to be checked by the reviewer of the PR 🔍:
If something doesn't apply please check the box and add a justification if the reason is non obvious.

• Is the PR title satisfactory? Is this part of a larger feature and should be grouped using > Changelog?
• PR description is clear and complete. It Links to relevant issue as well as docs and UI issues
• This will not break child repos: it doesn't hardcode values (.e.g "kumahq" as an image registry)
• IPv6 is taken into account (.e.g: no string concatenation of host port)
• Tests (Unit test, E2E tests, manual test on universal and k8s)
  • Don't forget ci/ labels to run additional/fewer tests
• Does this contain a change that needs to be notified to users? In this case, UPGRADE.md should be updated.
• Does it need to be backported according to the backporting policy? (this GH action will add "backport" label based on these file globs, if you want to prevent it from adding the "backport" label use no-backport-autolabel label)

[slonka]

There is a lot of utility code that I'm a bit surprise has not been implemented anywhere else. In general I can't find anything obviously wrong anywhere. Just one Q about the pipes.

[jijiechen]

A lot of thanks to your reviewing! @slonka

There is a lot of utility code that I'm a bit surprise has not been implemented anywhere else.

Agreed, and this is the same feeling that @lahabana had.

I expected there should be some existing SSH tunneling implementations at least. Well, there are such implementations, but those are either out-of-date or very small projects, I could not tell how well they are maintained (or even if they are actually maintained.)

Some example projects are:

• https://github.com/SommerEngineering/SSHTunnel
• https://github.com/glycerine/sshego
• https://github.com/rgzr/sshtun

The other parts of the RemoteDockendBackend mostly ported from our existing docker commands (which are powered by the terratest library). They are not complicated.

[slonka]

I don't see anything obviously wrong here, just the pipe thing that Jay explained.