LastPolicyRequestTimestamp.ps1

#region Get-CMInstallPath
function Get-CMInstallPath {
    function Split-CommandLine {
        [CmdletBinding()]
        Param
        (
            [Parameter(Mandatory = $false, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true, Position = 0)]
            [ValidateNotNullOrEmpty()]
            [string]$CommandLine
        )

        Begin {
            $Kernel32Definition = @'
        [DllImport("kernel32")]
        public static extern IntPtr GetCommandLineW();
        [DllImport("kernel32")]
        public static extern IntPtr LocalFree(IntPtr hMem);
'@
            $Kernel32 = Add-Type -MemberDefinition $Kernel32Definition -Name 'Kernel32' -Namespace 'Win32' -PassThru

            $Shell32Definition = @'
        [DllImport("shell32.dll", SetLastError = true)]
        public static extern IntPtr CommandLineToArgvW(
            [MarshalAs(UnmanagedType.LPWStr)] string lpCmdLine,
            out int pNumArgs);
'@
            $Shell32 = Add-Type -MemberDefinition $Shell32Definition -Name 'Shell32' -Namespace 'Win32' -PassThru

            if (!$CommandLine) {
                $CommandLine = [System.Runtime.InteropServices.Marshal]::PtrToStringUni($Kernel32::GetCommandLineW())
            }
        }

        Process {
            $ParsedArgCount = 0
            $ParsedArgsPtr = $Shell32::CommandLineToArgvW($CommandLine, [ref]$ParsedArgCount)

            Try {
                $ParsedArgs = @();

                0..$ParsedArgCount | ForEach-Object {
                    $ParsedArgs += [System.Runtime.InteropServices.Marshal]::PtrToStringUni(
                        [System.Runtime.InteropServices.Marshal]::ReadIntPtr($ParsedArgsPtr, $_ * [IntPtr]::Size)
                    )
                }
            }
            Finally {
                $Kernel32::LocalFree($ParsedArgsPtr) | Out-Null
            }

            $ret = @()

            # -lt to skip the last item, which is a NULL ptr
            for ($i = 0; $i -lt $ParsedArgCount; $i += 1) {
                $ret += $ParsedArgs[$i]
            }

            return $ret
        }
    }
    $ServicePathName = Get-CimInstance -ClassName Win32_Service -Namespace root/CIMV2 -Filter "Name='CcmExec'" | Select-Object -ExpandProperty PathName
    $ServicePathName | Split-CommandLine | Split-Path -Parent
}
#endregion Get-CMInstallPath
function ConvertFrom-CMTrace {
    [CmdletBinding()]
    param(
        [Parameter(Mandatory = $true, Position = 0, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true)]
        [string[]]$InputObject
    )

    begin {}

    process {
        if ([System.String]::IsNullOrEmpty($InputObject) -eq $true) { return}
        foreach ($Line In @($InputObject)) {
            try {
                if ($Line -match '\<\!\[LOG\[(?<Message>.*)?\]LOG\]\!\>\<time=\"(?<Time>.+)?\"\s+date=\"(?<Date>.+)?\"\s+component=\"(?<Component>.+)?\"\s+context="(?<Context>.*)?\"\s+type=\"(?<Type>\d)?\"\s+thread=\"(?<Thread>\d+)?\"\s+file=\"(?<File>.+)?\"\>') {
                    $LineMatch = $matches
                }
                if ($LineMatch.time -match '(?<Time>.+)(?<TZAdjust>[+|-])(?<TZOffset>\d{2,3})') {
                    $TimeMatch = $matches
                }

                $Date = $LineMatch.date
                $Time = $TimeMatch.time
                $TZAdjust = $TimeMatch.TZAdjust
                $TZOffset = $TimeMatch.TZOffset
                $TimeUTC = ([datetime]"$($Date) $($Time)").AddMinutes("$($TZAdjust)$($TZOffset)")

                [PSCustomObject][ordered]@{
                    Message     = [string]$LineMatch.message
                    Date        = [string]$LineMatch.date
                    Time        = [string]$LineMatch.time
                    Component   = [string]$LineMatch.component
                    Context     = [string]$LineMatch.context
                    Type        = [int]$LineMatch.type
                    Thread      = [long]$LineMatch.thread
                    File        = [string]$LineMatch.file
                    FileName    = [string]($LineMatch.file -split ':')[0]
                    LineNumber  = [long]($LineMatch.file -split ':')[1]
                    TimeWritten = $TimeUTC.ToLocalTime()
                }
            }
            catch {
                throw $_
            }
        }
    }

    end {}
}

$CMInstallPath = Get-CMInstallPath
$LastPolicyRequest = Get-Content -Path $CMInstallPath\logs\policyagent.log | ConvertFrom-CMTrace -ErrorAction SilentlyContinue | Where-Object Message -match '^Requesting Machine policy assignments from authority' | Select-Object -Last 1 -ExpandProperty TimeWritten