Winter Scripting Games 2013 - Practice Event 1

The Winter Scripting Games 2013 started last week with the first practice event.

Unfortunately for me, I was not able to post my script on time. The first Practice event was due on the Tuesday, 5th of February... 11:59 PM GMT! I assume I had until midnight my time..... (My timezone is East GMT-5) 

;-(

If you want to join the Winter Scripting Games, check the following TheScriptingGames website for more information and the The Competitor Guide.

Summary: Practice Event 1 - 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.
Minimum Requirements 

Optional Criteria

• Display optional verbose output showing the computer name being contacted

My Script

Function Get-DiskSizeInfo {
        <#
        .DESCRIPTION
        Check the Disk(s) Size and remaining freespace.

        .PARAMETER ComputerName
        Specify the computername(s)

        .INPUTS
        System.String

        .OUTPUTS
        System.Management.Automation.PSObject

        .EXAMPLE
        Get-DiskSizeInfo
        
        Get the drive(s), Disk(s) space, and the FreeSpace (GB and Percentage)

        .EXAMPLE
        Get-DiskSizeInfo -ComputerName SERVER01,SERVER02

        Get the drive(s), Disk(s) space, and the FreeSpace (GB and Percentage)
        on the Computers SERVER01 and SERVER02

        .EXAMPLE
        Get-Content Computers.txt | Get-DiskSizeInfo

        Get the drive(s), Disk(s) space, and the FreeSpace (GB and Percentage)
        for each computers listed in Computers.txt

        .NOTES
        NAME  : Get-DiskSizeInfo
        AUTHOR: Francois-Xavier Cat
        EMAIL : fxcat@LazyWinAdmin.com
        DATE  : 2013/02/05 
    
        .LINK
        http://lazywinadmin.com
        #>

    [CmdletBinding()]
    param(
        [Parameter(ValueFromPipeline=$True)]
        [string[]]$ComputerName = $env:COMPUTERNAME
    )
    BEGIN {# Setup
        }
    PROCESS {
        Foreach ($Computer in $ComputerName) {
            
            Write-Verbose -Message "ComputerName: $Computer - Getting Disk(s) information..."
            try {
                # Set all the parameters required for our query
                $params = @{'ComputerName'=$Computer;
                            'Class'='Win32_LogicalDisk';
                            'Filter'="DriveType=3";
                            'ErrorAction'='SilentlyContinue'}
                $TryIsOK = $True
                
                # Run the query against the current $Computer    
                $Disks = Get-WmiObject @params
            }#Try
            
            Catch {
                "$Computer" | Out-File -Append -FilePath c:\Errors.txt
                $TryIsOK = $False
            }#Catch
            
            if ($TryIsOK) {
                Write-Verbose -Message "ComputerName: $Computer - Formating information for each disk(s)"
                foreach ($disk in $Disks) {
                    
                    # Prepare the Information output
                    Write-Verbose -Message "ComputerName: $Computer - $($Disk.deviceid)"
                    $output =         @{'ComputerName'=$computer;
                                    'Drive'=$disk.deviceid;
                                    'FreeSpace(GB)'=("{0:N2}" -f($disk.freespace/1GB));
                                    'Size(GB)'=("{0:N2}" -f($disk.size/1GB));
                                    'PercentFree'=("{0:P2}" -f(($disk.Freespace/1GB) / ($disk.Size/1GB)))}
                    
                    # Create a new PowerShell object for the output
                    $object = New-Object -TypeName PSObject -Property $output
                    $object.PSObject.TypeNames.Insert(0,'Report.DiskSizeInfo')
                    
                    # Output the disk information
                    Write-Output -InputObject $object
                    
                }#foreach ($disk in $disks)
                
            }#if ($TryIsOK)
            
        }#Foreach ($Computer in $ComputerName)
        
    }#PROCESS
    END {# Cleanup
        }
}#Function Get-DiskSizeInfo

Using the function:

By default, if you do not specify a computername, the function will query the localhost:  $env:computername

Getting some Help

Get-Help Get-DiskSizeInfo -Full

The Function's help has been wrote between the lines 2 and 39.
More information on technet: about_Comment_Based_Help

Use the Verbose switch

Get-DiskSizeInfo -ComputerName XAVIER -Verbose

The verbose switch is available since we use the [CmdletBinding()] at the line 41.
Check the nice article from the scripting guy: CmdletBinding Attribute Simplifies PowerShell Functions

Thanks for reading, hope this help some folks out there.