Windows - howto use powershell commands in hooks?

[goebbe]

Testing Vykar 0.16 on Windows 10
I try to specify a before hook. The backup should only run, when the specified condition is "True"

The following command, works well, when I run it directly in the Windows PowerShell:
$hour = (Get-Date).Hour; $hour -ge 7 -and $hour -lt 23

This command returns "False" or "True", when I run it in the PowerShell.

When I simply add this command to a before hook, as follows, the hook does not work as expected:

    hooks:
      before: >-
        $hour = (Get-Date).Hour; $hour -ge 7 -and $hour -lt 23

I see two issues:

1. When the hook is running, the PowerShell Window is visibly displayed on the screen for a short period, which is distracting.
2. Even if the condition is not satisfied - the backup is running anyway, so somehow the output of the command is not properly visible to Vykar.

Is there a way to

• run the PowerShell command in the background (without the PowerShell window-flashing)?
• get the return value piped to stdout/ Vykar?

Any advice/ hint is welcome.

[goebbe]

This is what I found, after further investigation:

Apparently, the problem is due to the fact that, independent of the condition value, PowerShell will exit with status 0 (successful) if the condition could be tested.
With Windows PowerShell, the rational is, that the condition testing itself ran successful, even when the result of the test is "False". This behaviour is different from a Linux Shell, where a "False" condition would exit with "0", i.e. no success.

The standard workaround seems to be to use if/else conditions to explicitly set exit to 0 or 1, as follows:
$hour = (Get-Date).Hour; if ($hour -ge 7 -and $hour -lt 23) { exit 0 } else { exit 1 }

I tested this command, and it seems to work as expected. 👍

The following hook checks if current hour is between 7h and 23h. No backups are started if this test fails:

    hooks:
      before: >-
        $hour = (Get-Date).Hour; if ($hour -ge 7 -and $hour -lt 23) { exit 0 } else { exit 1 }

@m3nu: For the Power-Shell "Window-flashing", apparently there is a way to execute PowerShell commands from Rust using "creation_flags" to avoid that the PowerShell Window is created at all.
Edit: I opened #149 for the window-flashing.