Add explicit datatype string for units

Fixes issue, where Convert-Bytes throws error, because $Value is not a string.

Author: Crited

plugins/Invoke-IcingaCheckMemory.psm1

@@ -13,7 +13,7 @@
    PS>Invoke-IcingaCheckMemory -Verbosity 3 -Warning 60 -Critical 80
    [WARNING]: % Memory Check 78.74 is greater than 60
 .EXAMPLE
-   PS> Invoke-IcingaCheckMemory -WarningPercent 0:30 -CriticalPercent 0:50
+   PS> Invoke-IcingaCheckMemory -WarningPercent 30 -CriticalPercent 50
    [WARNING] Check package "Memory Usage" - [WARNING] Memory Percent Used
    \_ [WARNING] Memory Percent Used: Value "48.07%" is greater than threshold "30%"
    | 'memory_percent_used'=48.07%;0:30;0:50;0;100 'used_bytes'=3.85GB;;;0;8
@@ -55,12 +55,12 @@
 function Invoke-IcingaCheckMemory()
 {
    param(
-      [string]$Critical      = $null,
-      [string]$Warning       = $null,
-      $CriticalPercent       = $null,
-      $WarningPercent        = $null,
+      [string]$Critical        = $null,
+      [string]$Warning         = $null,
+      $CriticalPercent = $null,
+      $WarningPercent  = $null,
       [ValidateSet(0, 1, 2, 3)]
-      [int]$Verbosity        = 0,
+      [int]$Verbosity          = 0,
       [switch]$NoPerfData
    );
 
@@ -69,23 +69,23 @@ function Invoke-IcingaCheckMemory()
 
    # Auto-Detect?
    If (($MemoryData['Memory Total Bytes'] / [math]::Pow(2, 50)) -ge 1) {
-      $CalcUnit = 'PiB';
-      $Unit = "PB";
+      [string]$CalcUnit = 'PiB';
+      [string]$Unit = "PB";
    } elseif (($MemoryData['Memory Total Bytes'] / [math]::Pow(2, 40)) -ge 1) {
-      $CalcUnit = 'TiB';
-      $Unit = "TB";
+      [string]$CalcUnit = 'TiB';
+      [string]$Unit = "TB";
    } elseif (($MemoryData['Memory Total Bytes'] / [math]::Pow(2, 30)) -ge 1) {
-      $CalcUnit = 'GiB';
-      $Unit = "GB";
+      [string]$CalcUnit = 'GiB';
+      [string]$Unit = "GB";
    } elseif (($MemoryData['Memory Total Bytes'] / [math]::Pow(2, 20)) -ge 1) {
-      $CalcUnit = 'MiB';
-      $Unit = "MB";
+      [string]$CalcUnit = 'MiB';
+      [string]$Unit = "MB";
    } elseif (($MemoryData['Memory Total Bytes'] / [math]::Pow(2, 10)) -ge 1) {
-      $CalcUnit = 'KiB';
-      $Unit = "KB";
+      [string]$CalcUnit = 'KiB';
+      [string]$Unit = "KB";
    } else {
-      $CalcUnit = 'B';
-      $Unit = "B";
+      [string]$CalcUnit = 'B';
+      [string]$Unit = "B";
    }
 
    If ([string]::IsNullOrEmpty($Critical) -eq $FALSE) {