How can you set a time limit for a PowerShell script to run for?

Question

I want to set a time limit on a PowerShell (v2) script so it forcibly exits after that time limit has expired.

I see in PHP they have commands like set_time_limit and max_execution_time where you can limit how long the script and even a function can execute for.

With my script, a do/while loop that is looking at the time isn't appropriate as I am calling an external code library that can just hang for a long time.

I want to limit a block of code and only allow it to run for x seconds, after which I will terminate that code block and return a response to the user that the script timed out.

I have looked at background jobs but they operate in a different thread so won't have kill rights over the parent thread.

Has anyone dealt with this or have a solution?

Thanks!

Answer 1

Here is an example of using a Timer. I haven't tried it personally, but I think it should work:

function Main
{
    # do main logic here
}

function Stop-Script
{
    Write-Host "Called Stop-Script."
    [System.Management.Automation.Runspaces.Runspace]::DefaultRunspace.CloseAsync()
}

$elapsedEventHandler = {
    param ([System.Object]$sender, [System.Timers.ElapsedEventArgs]$e)

    Write-Host "Event handler invoked."
    ($sender -as [System.Timers.Timer]).Stop()
    Unregister-Event -SourceIdentifier Timer.Elapsed
    Stop-Script
}

$timer = New-Object System.Timers.Timer -ArgumentList 2000 # setup the timer to fire the elapsed event after 2 seconds
Register-ObjectEvent -InputObject $timer -EventName Elapsed -SourceIdentifier Timer.Elapsed -Action $elapsedEventHandler
$timer.Start()

Main