I'm creating a PowerShell script for DPM which outputs offsite ready tapes. The below code takes a few seconds to complete the DPM connection and to return the query, which is fine.
# Connect to local DPM server
$DPMServer = $env:COMPUTERNAME
Connect-DPMServer -DPMServerName $DPMServer | Out-Null
# Get the DPM libary
$DPMLib = Get-DPMLibrary
#Format output
$Formatting = @{Expression={$_.Barcode}; Label="Barcode "; Width=12},
@{Expression={"{0:MM/dd/yyyy HH:mm tt}" -f $_.CreationDate}; Label="Creation Date "; Width=23},
@{Expression={$_.DisplayString}; Label="Tape Label "; Width=28},
@{Expression={"{0,15:N0}" -f $_.DataWrittenDisplayString}; Label="Data Written "}
#Calculate Monday at midnight of this week
$Monday = (Get-Date).AddDays((-1 * (Get-Date).DayOfWeek.Value__) 1).Date
# Get specific tapes
$Tapes = Get-DPMTape -DPMLibrary $DPMLib |
Where-Object {$_.Barcode -notlike "CLN*"} |
Where-Object {$_.DisplayString -notlike "Free"} |
Where-Object {$_.CreationDate -gt $Monday} |
Sort-Object Barcode |
Format-Table -Property $Formatting
Write-Host "`nOffsite Ready Tapes:" -ForegroundColor Cyan
#Output tapes
$Tapes
This outputs like so:
My question is how do I now select just the barcodes listed within the $Tapes array, and output them (below what I already have) as a comma delimited list, without running the DPM query again. I've tried all sorts of things with no luck, I'm missing something obvious.
If I do a second connection to DPM, I can do it like this, but I'm trying to avoid doubling the time it takes to run. This is part of my original newbie script that I'm trying to better.
# Define DPM server to connect to
$DPMServer = $env:COMPUTERNAME
Connect-DPMServer -DPMServerName $DPMServer | Out-Null
# Get the DPM libary
$DPMLib = Get-DPMLibrary
# Get tape display strings and barcodes, sort by barcode
$Tapes = Get-DPMTape -DPMLibrary $DPMLib | Select-Object CreationDate, DisplayString, Barcode | Sort-Object Barcode
# Create empty array
$DPMTapesForOffsite = @()
Write-Host "`nOffsite Ready Tapes:`n" -ForegroundColor Cyan
foreach ($_ in $Tapes) {
# Exclude cleaning tapes
if ($_.Barcode -notlike "CLN*") {
# Exclude marked as free
if ($_.DisplayString -notlike "Free") {
$TimeStamp = Get-Date $_.CreationDate
# Timestamp is from this week
if ($Timestamp -gt $Monday) {
$DPMTapesForOffsite = $DPMTapesForOffsite $_.barcode
Write-Host $_.barcode
}
}
}
}
# Format tape list as comma delimited
$DPMTapesForOffsite = $DPMTapesForOffsite -join ","
I'm missing some obvious, any help would greatly be appreciated.
CodePudding user response:
# Omit Format-Table initially, so as to store actual *data* in $tapes,
# not *formatting instructions*, which is what Format-* cmdlets return.
$tapes = Get-DPMTape -DPMLibrary $DPMLib |
Where-Object {$_.Barcode -notlike "CLN*"} |
Where-Object {$_.DisplayString -notlike "Free"} |
Where-Object {$_.CreationDate -gt $Monday} |
Sort-Object Barcode
# Now you can apply the desired formatting.
Write-Host "`nOffsite Ready Tapes:" -ForegroundColor Cyan
$tapes | Format-Table -Property $Formatting
# Thanks to PowerShell's member enumeration feature,
# accessing property .Barcode on the entire $tapes *collection*
# conveniently returns its *elements'* property values.
# -join ',' joins them with commas.
$tapes.Barcode -join ','
Format-*
cmdlets output objects whose sole purpose is to provide formatting instructions to PowerShell's output-formatting system - see this answer.
In short: only ever use Format-*
cmdlets to format data for display, never for subsequent programmatic processing.
This answer explains member enumeration.