Add support for ssh tunnelling to a jump server

[keithel-qt]

This allows one to tunnel to a jumpserver right from the toolbox.

Example usage:

cargo make run --ssh-tunnel="[email protected]" --ssh-remote-bind-address="10.1.52.164:55555"

[keithel-qt]

One remaining mypy issue - Not sure how to resolve it.
I only incude the sshtunnel module if the --ssh-tunnel option is provided - which mypy doesn't like.
The sshtunnel module is specified as an optional module in pyproject.toml.

I suppose I could move this whole ssh tunneling logic to a separate .py file - that might fix the issue, but I don't really want to spend much time on this. It is just a convenience feature.

[john-michaelburke]

One remaining mypy issue - Not sure how to resolve it. I only incude the sshtunnel module if the --ssh-tunnel option is provided - which mypy doesn't like. The sshtunnel module is specified as an optional module in pyproject.toml.

I suppose I could move this whole ssh tunneling logic to a separate .py file - that might fix the issue, but I don't really want to spend much time on this. It is just a convenience feature.

Yeah I was thinking this might be better as a cargo make command, if you can do it through bash. But if this works and it doesn't add much overhead by all means.

[keithel-qt]

Yeah I was thinking this might be better as a cargo make command, if you can do it through bash. But if this works and it doesn't add much overhead by all means.

I would rather it be part of the app startup, as it will open the tunnel when the app starts, and tear it down when it stops.
Doing so with a separate process requires some extra work watching the python process, and that isn't as easy.

The changes I made should have very, very minimal performance impact. If the sshtunnel module isn't installed, it will try importing it, set the FEATURE_SSHTUNNEL flag, and do two checks on that flag on startup - once for adding the command line options to the parser, and a second one for doing the command line arg validation for these args. Then on handling of CLI args it will check once for args.ssh_tunnel.