apk not being found with alpine using dropbear sshd.

Describe the bug

I’m using infra on alpine with dropbear sshd and apk is not being found. I did try openssh sshd and it works, but for some of my setups I’d prefer to use dropbear.

To Reproduce

# this is on a temporary scratch install of alpine
pyinfra --user root 192.168.122.227 apk.packages rsync
--> Loading config...
--> Loading inventory...

--> Connecting to hosts...
    [192.168.122.227] Connected

--> Preparing operation...
    [192.168.122.227] Ready: apk.packages

--> Proposed changes:
    Ungrouped:
    [192.168.122.227]   Operations: 1   Commands: 1   

--> Beginning operation run...
--> Starting operation: Apk/Packages (rsync)
    [192.168.122.227] sh: apk: not found
    [192.168.122.227] Error
--> pyinfra error: No hosts remaining!
Wed 29Dec21 02:40:15 ~

Expected behavior

I expected a way to specify the path to apk. I did a sed replace of apk with /sbin/apk and it works.

sed "s,'apk,'/sbin/apk," .local/lib/python3.10/site-packages/pyinfra/facts/apk.py -i
sed "s,'apk,'/sbin/apk," .local/lib/python3.10/site-packages/pyinfra/operations/apk.py -i
sed "s,'apk,'/sbin/apk," .local/lib/python3.10/site-packages/pyinfra/operations/server.py -i

Should there be a way to configure an absolute path for remote package management commands? I could make a PR if we can agree on how this could be made configurable.

Meta

• Include output of pyinfra --support.

--> Support information:

    If you are having issues with pyinfra or wish to make feature requests, please
    check out the GitHub issues at https://github.com/Fizzadar/pyinfra/issues .
    When adding an issue, be sure to include the following:

    System: Linux
      Platform: Linux-5.15.11-arch2-1-x86_64-with-glibc2.33
      Release: 5.15.11-arch2-1
      Machine: x86_64
    pyinfra: v1.5
    Executable: /home/dwight/.local/bin/pyinfra
    Python: 3.10.1 (CPython, GCC 11.1.0)

• How was pyinfra installed (source/pip)?

pip install --user pyinfra

[bogen85]

@Fizzadar I think on the PATH issue, dropbear appears to be the culprit as it is not setting the path and is not honoring the ssh config for environment variables. The documentation for dropbear claims it sets them, and I’ll have to dig deeper into that.

Regarding systemd-nspawn, yes, I’m using the @chroot connector along with a chroot wrapper script in my path. See #731 for more details. I’m open to either (new connector or new configuration field) as long as I have the some functionality I’m getting from the wrapper (systemd-nspawn run with sudo, not all of pyinfra) (with ansible and chroot, all of ansible has to be run as root).

[bogen85]

It is working now on a fresh setup (no ~/.ssh/config specifics needed). Have not determined what was causing it to not work earlier.

Continuing discussion on #731for chroot.