Merge pull request #40 from hic-infra/autoshutdown-windows

Autoshutdown for large Windows workspaces

modules/autohibernate.ps1

@@ -1,7 +1,55 @@
-powercfg /change hibernate-timeout-ac $Env:AUTOHIBERNATE_TIME
 
-$shell = New-Object -ComObject WScript.Shell
-$shortcut = $shell.CreateShortcut([Environment]::GetFolderPath("Desktop") + "\Hibernate.lnk")
-$shortcut.TargetPath = "C:\Windows\System32\shutdown.exe"
-$shortcut.Arguments = "/h"
-$shortcut.Save()
+$ramGB = (Get-CimInstance Win32_PhysicalMemory).Capacity / 1024 / 1024 / 1024
+
+if ($null -eq $Env:AUTOHIBERNATE_TIME) {
+    $Env:AUTOHIBERNATE_TIME = 120
+}
+
+# Windows cannot hibernate (at least in AWS) if it has more than 16GB
+# of RAM. Instead we'll forcefully shutdown the instance because EC2
+# is expensive!
+if ($ramGB -gt 16) {
+    $idleScript = "C:\workdir\idleshutdown.ps1"
+    New-Item $idleScript
+    Set-Content $idleScript @"
+`$quser = quser | ForEach-Object -Process { `$_ -replace '\s{2,21}',',' } | ConvertFrom-Csv
+`$session = `$quser | Where-Object {{ `$_.SessionName -like "rdp-tcp*" -or `$_.State -eq "Disc" }}
+
+# quser time is in the following formats, depending on duration.
+# "days+hours:minutes" or "hours:minutes" or "minutes" or, if
+# less than a minute "."
+# We need to convert it to something we can cast to TimeSpan,
+# i.e. "days.hours:minutes" or just "hours:minutes"
+`$idleTime = (`$session.'IDLE TIME').Replace('+', '.')
+if (`$idleTime -eq ".") { `$idleTime = 0 }
+if (`$idleTime -notmatch "\.") { `$idleTime = "0.0:`$idleTime" }
+`$idleTime = [TimeSpan]`$idleTime
+
+if (`$idleTime.TotalMinutes -ge $Env:AUTOHIBERNATE_TIME) {
+  Stop-Computer -ComputerName localhost -Force
+}
+"@
+
+    $action = New-ScheduledTaskAction -Execute powershell.exe `
+      -Argument "-File $idleScript"
+    $trigger = New-ScheduledTaskTrigger -Once -At (Get-Date) `
+      -RepetitionInterval (New-TimeSpan -Minutes 1) `
+      -RepetitionDuration (New-TimeSpan -Days 3650)
+    $principal = New-ScheduledTaskPrincipal `
+      -UserID "NT AUTHORITY\SYSTEM" `
+      -LogonType ServiceAccount
+
+    Register-ScheduledTask "ShutdownIdle" `
+      -Action $action `
+      -Principal $principal `
+      -Trigger $trigger `
+      -Force
+} else {
+    powercfg /change hibernate-timeout-ac $Env:AUTOHIBERNATE_TIME
+
+    $shell = New-Object -ComObject WScript.Shell
+    $shortcut = $shell.CreateShortcut([Environment]::GetFolderPath("Desktop") + "\Hibernate.lnk")
+    $shortcut.TargetPath = "C:\Windows\System32\shutdown.exe"
+    $shortcut.Arguments = "/h"
+    $shortcut.Save()
+}