Winter Scripting Camp 2013 - #1 Advanced Problem

First a bit background on the Winter Scripting Camp, this is the first time a Scripting camp is happening. The sole purpose of this is to make the scripters all over the world sharpen their skills for the upcoming "Scripting Games 2013". These games are awesome..so much stuff to learn and personally what I like about them are they are very practical and work-oriented whatever the problems asked are very real-life PRODUCTION environment problems. This develops your approach towards the problems which you might face later in your Work Environment. I learned a whole lot of lessons while participating for last year's Scripting Games in Beginner's category. Hopefully, the Scripting Camp will make me a bit sharper this time :P


Following is the first problem of the Winter Scripting Camp...See how practical the problem is :P

#1 Advanced Section
Sizing up the Disks

You have been asked to create a Windows PowerShell advanced function named Get-DiskSizeInfo. It must accept one or more computer names, and use WMI or CIM to query each computer. For each computer, it must display the percentage of free space, drive letter, total size in gigabytes, and free space in gigabytes. If a specified computer cannot be contacted, the function must log the computer name to C:\Errors.txt and display no error message.



Below is my submission. The formatting is a bit buggy . I will edit the post later on mistakes I did here and what I learned:

<#
.Synopsis
  Gets the Disk Size Info
.DESCRIPTION
  Uses WMI to query the disk size info, then spits out custom Objects with
  required properties
.EXAMPLE
  "Server1","server2" | Get-DiskSizeInfo  -Verbose
.EXAMPLE
  Get-DiskSizeInfo -ComputerName "server1","server2"  -ErrorLogFile D:\errors.txt
  This example shows how to run this function against a list of computers and specifying
  an alternate log file for computers not online.
.INPUTS
  [system.string[]]
.OUTPUTS
  [System.Management.Automation.PSCustomObject]
#> 
function Get-DiskSizeInfo 
{ 
  [CmdletBinding()] 
  [OutputType([psobject])] 
  Param 
  ( 
  # Param1 help description 
    ValueFromPipelineByPropertyName=$true, 
  ValueFromRemainingArguments=$false, 
  Position=0 )> 
  [ValidateNotNullOrEmpty()] 
  [Alias("CN","server")] 
  [string[]]$ComputerName=[environment]::MachineName , 

  # Param2 help description 
   
  [ValidateScript({Test-Path -path (split-path -parent $_) -pathtype container })] 
  [string] 
  $ErrorLogFile="C:\Errors.txt" 

  ) 
  Process 
  { 
  Foreach ($computer in $ComputerName) { 
  if (Test-Connection -ComputerName $Computer -Count 2 -Quiet){ 
  Write-Verbose "$computer is online...getting disk size info" 
 
  try { 
  $wmidiskinfo = Get-WmiObject -Class Win32_LogicalDisk -Filter “DriveType = 3" -ErrorAction stop 
  foreach ($disk in $wmidiskinfo) { 
  New-Object -TypeName PSObject -Property @{ 
  ComputerName=$computer 
  Drive=$disk.DeviceID 
  Size=$disk.Size/1GB 
  'FreeSpace(in GB)'=$disk.Freespace/1GB 
  'FreeSpace(%)'=($disk.Freespace/$disk.Size) * 100 -as [int] } 
  } 
  } 
 
 
  catch { 
  Write-Verbose "Error while getting WMI Object or Creating PSObject for $computer" 
  $Error[0].Exception 
  } 
  }#end if block 
  else { 
  Write-Verbose "$computer is not online..logging" 
  if (Test-Path $ErrorLogFile){ 
  $computer | Out-File -FilePath $ErrorLogFile -Append 
  } 
  else{ 
  $Computer | Out-File -FilePath $ErrorLogFile 
  } 
  } 
 
  }#end foreach outer 
 
  }#end Process 
}#end Function