Run Background Commands after Every Command (Part II)

The first part of this post began on PowerShell.org. Start there, and it’ll get you to Part I: http://powershell.org/wp/2015/10/12/run-background-commands-after-every-command.

Recently I shared a small function I wrote to replace my prompt function. In addition to creating the prompt (PS: C\>) each time one command ended, it would run some background commands. In my attempt to take advantage of this function, I added code that would modify the WindowTitle, the text at the top of the console host or ISE, to indicate if there were any background jobs. Today, I’ve improved the function.

The additions I made include all of the following:
– Uses the singular word “job” when there is only one background job.
– Uses the plural word “jobs” when there is more than one background job.
– Adds an asterisk (*) when any job is actively running.
– Adds a plus sign (+) when any job has more data.

Here’s the full, updated function, and some sequential images beneath that. I’ve dumped the nested If statement for a switch statement, improving the function’s readability. Before you get into this, there’s something to consider. The indicators are only as accurate as the last time the prompt function was invoked. They won’t update without the user pressing the Enter key. That said, it’s quite convenient that you can determine if a background job is still running by pressing Enter. You don’t even have to type anything.

Function Prompt {
    If (-Not($OriginalTitle)) {
        $Global:OriginalTitle = $Host.UI.RawUI.WindowTitle
    }

    If (Get-Job) {
        $Job = Get-Job
        Switch ($Job) {
            {$Job.State -eq 'Running'} {$State = '*'}
            {$Job.HasMoreData -eq $true} {$MoreData = '+'}
            {$Job.Count -eq 1} {$Host.UI.RawUI.WindowTitle = "[$($State)Job$($MoreData)] $OriginalTitle"; break}
            {$Job.Count -gt 1} {$Host.UI.RawUI.WindowTitle = "[$($State)Jobs$($MoreData)] $OriginalTitle"}
        }
    } Else {
        $Host.UI.RawUI.WindowTitle = $OriginalTitle
    }

    "PS $($executionContext.SessionState.Path.CurrentLocation)$('>' * ($nestedPromptLevel + 1)) "
}

Run-background-commands-after-every-command-PartII-01

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Run-background-commands-after-every-command-PartII-03

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Update: After looking at this a few more times, I decided to move the asterisk indicator (running jobs) to the back of the word Job, or Jobs, next the plus sign indicator (has more data). I thought it looked better. The code changes I made, are seen below, and a comparison image is down there, too. Cheers!

Function Prompt {
...
            {$Job.Count -eq 1} {$Host.UI.RawUI.WindowTitle = "[Job$($State)$($MoreData)] $OriginalTitle"; break}
            {$Job.Count -gt 1} {$Host.UI.RawUI.WindowTitle = "[Jobs$($State)$($MoreData)] $OriginalTitle"}
...
}

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