Dynamic Variable Values

Once again, my good friend from Texas asked me for a little PowerShell assistance. Being an old Cold Fusion junkie, he sent me his cryptic CF code:

Disclaimer (Blogger hates Angle Brackets)
cfset variable1="blah"
cfset var2="yada"

This statement would've then returned the value of "#blahyada#"
cfoutput #Evaluate("#variable1#")var2# cfoutput

It is basically a self-renaming variable based on the value of another variable - no idea if PowerShell can do that.

After my brief Cold Fusion viewing induced nausea subsided, I decided to help him. This is the sample I sent him:
$DallasAddress = "123 Cowboy Ave."
$ColumbusAddress = "456 Hayes St."
$ClevelandAddress = "910 Kosar Blvd."

$loc = "Dallas"
# Returns "123 Cowboy Ave."
(Get-Variable ($loc+"Address")).value

He is now happy and has learned a little bit more PowerShell. As for me, he has added yet another 6 bottles of my favorite beverage to the till.
Enjoy!

Query DNS with PowerShell

Following is a script that will enable you to query DNS for duplicate records. Be sure to change the location of the output file!

# Using WMI, retrieve all the duplicate DNS records
$DNS = Get-WmiObject -ComputerName 'DNS-Server' `
   -Namespace 'root\MicrosoftDNS' `
   -Class MicrosoftDNS_AType `
   -Filter "ContainerName='Your Container'" | `
Group-Object OwnerName | Where-Object {$_.Count -gt 1}

# Create our CSV file to hold the data
$file = 'c:\temp\DNS.csv'
New-Item -ItemType file -Path $file -Force 
Add-Content -Path $file -Value "Name,IPAddress"

# Iterate of the DNS items grabbing the name and IPAddress
foreach ($item in $DNS) {
    foreach ($IPAddresses in $item.Group) {
        $value = "{0},{1}" -f $item.name,$IPAddresses.IPAddress
        Add-Content -Path $file -Value $value
    }
}

Results should look something like:

Name	IPAddress
Server1	10.194.111.22
Server2	10.140.111.22
ServerA	10.333.19.121
ServerB	10.333.131.24

Enjoy!

Calling a Web Service with PowerShell

I often need to be notified of a certain condition when a scheduled script executes.
With PowerShell V2, I can take advantage of our internal paging web service by using the New-WebServiceProxy cmdlet to take care of this notification.

Check out the help on this cmdlet to see a full list of capabilities. Help New-WebServiceProxy -Full

Before we dive into the actual call, lets interrogate the web service to see what it can do.
# Create a proxy for the Paging web service
$page = New-WebServiceProxy -Uri 'http://InternalPagingService/pageservice.asmx'

#List the methods
$page Get-Member -MemberType Method
You should see something like this:

The method we are going to use is RequestSinglePage.

Enter the following to see the expected parameters:
($page Get-Member -Name RequestSinglePage).definition

Looking at the end of the definition we see 2 parameters:
- string PagerId
- string NumericOrAlphaMessage

We now have all we need to page from script!
$page.RequestSinglePage('3141','Testing Page Web Service from PowerShell')

If you need confirmation of the Web Service call, you can look at the FunctionStatus property of the executed Web Service.
($page.RequestSinglePage('3141','Test Page from PowerShell')).FunctionStatus

This returns - SUCCESS

Wrapping this web service call around some return code if fairly straight forward and is left as an exercise for the reader.

If you don't have an internal Web Service handy, try out http://www.webservicex.net/WeatherForecast.asmx

Enjoy!

Using F# BigInt in PowerShell

Occasionally I have the need to utilize large precise numbers within PowerShell. Unfortunately, the native data types that we can use are limited in their precision.

• Float: 7 digits
• Double: 16 digits
• Decimal: 29 digits

I have been researching F# and came across a data type called BigInt. I now knew that I could go back to PowerShell and take advantage of this type.

The process to do so is straight forward:
First add a reference to the FSharp.Core assembly

Add-Type -Path 'C:\Program Files (x86)\FSharp-1.9.6.16\bin\fSharp.Core.dll'

Now you do things like:
PS C:> [Microsoft.FSharp.Math.BigInt]::Pow(17,71).toString()
PS C:>2300771122759378216336589429524308
0278517973481542540644504860767306
72752491528319986033

So if you are a fan of http://projecteuler.net/ you now have another tool you can utilize.

Enjoy!

Defining Object Formatting or "How to always show Military time"

A former colleague of mine at the OSU Medical Center recently asked a PowerShell related question.

Wait - Stop - Let's start over. I must digress a moment, please be patient as I give this former colleague of mine an appropriate introduction.

This Buckeye transplant to the state of Texas is much more then a former workmate, his legacy persists in innumerable ways. I won't take your time listing many of them, but I do have to share at least one. Notice the name of my blog? It isn't named after a South Park character, nor is it named after some pirate fetish. No this transplanted Buckeye is the source of FatBeard. He has a peculiar ability to derive nicknames that persist way beyond any code or script he has ever written. I fell prey to his moniker making over 3 years ago.

OK - now that you know how FatBeard came to be, lets move on with the PowerShell related post.

Texas asked me the following:

When I type Get-ChildItem (dir, ls) and get a file listing I want to see the LastWriteTime in Military format. Easy enough! I sent him this:

Get-ChildItem | select @{Name="LWT";Expression={"{0:d} {0:HH}:{0:mm}" -f ($_.LastWriteTime)}}

His response went something like this (paraphrased for the children in the audience) . "You obtuse gluteus maximus, why would I want to type that each and every time I need a directory listing." Admittedly, he had a point.

Thus begins my first foray into extending types. Using this as my guide (http://msdn.microsoft.com/en-us/library/ms714665(VS.85).aspx), I was able to quickly accomplish the task.

My steps were as follows:

1. Navigate to C:\Windows\System32\WindowsPowerShell\v1.0 and make a copy of FileSystem.format.ps1xml
2. Rename the copied file (CustomFileSystem.format.ps1xml)
3. Open the renamed file and look for the tag.
4. You should find something like this -
   [String]::Format("{0,10} {1,8}", $_.LastWriteTime.ToString("d"), $_.LastWriteTime.ToString("t"))
   
5. As you can see, this handles the LastWriteTime formating for FileSystem related information. All we need to do is change it to meet our need. This should do -
   
6. [String]::Format("{0,10} {1,2}:{2,2}:{3,2}", $_.LastWriteTime.ToString("d"),
   $_.LastWriteTime.ToString("HH"), $_.LastWriteTime.ToString("mm"),
   $_.LastWriteTime.ToString("ss"))
   
7. Save the file.
8. We now need to load the new formatting. Easy enough!
   Update-FormatData -prependPath 'C:\WINDOWS\system32\windowspowershell\v1.0\ CustomFileSystem.format.ps1xml'
9. Verify your custom formatting by typing a few Get-ChildItem commands.

Now that wasn't to hard was it! Well Texas is happy now and you know how to modify object formatting (and how FatBeard came to be).

Enjoy!

PowerShell and ZedGraph – Example 3

Welcome to part three in our PowerShell/ZedGraph series. Make sure you take a look at Part 1 & Part 2 before you continue on. Before we jump into more advanced features, I thought I would demonstrate how to populate the chart with real data. Apparently some were not impressed by the Yuengling consumption example (a fictitious one at that!).

We will use the ever diligent Get-Process cmdlet for our "real" data. The end result will look something like this:

Pretty no?

The code:

#Load the zedgraph dll
$ZedGraphDll = "C:\zedgraph_dll_v5.1.5\ZedGraph.dll"
[System.Reflection.Assembly]::LoadFrom($ZedGraphDll) | out-null

# Create a WinForm to serve as a container
$global:form = new-object Windows.Forms.form
$form.Size = new-object System.Drawing.Size @(500,400)

# Create a ZedGraphControl
$zgc = new-object -typename ZedGraph.ZedGraphControl
$zgc.GraphPane.Title.Text = "Processes"
$zgc.GraphPane.XAxis.Title.Text = "Process"
$zgc.GraphPane.YAxis.Title.Text = "WS(MB)"

# Go fetch me some processes data
$WS = @{Name='WS';Expression={"{0:#}" -f ($_.WorkingSet/1KB)}}
$processes = Get-Process | where {$_.WorkingSet -gt 30MB} | Sort Name | select $WS, Name

$a = $b = @()
foreach($Process in $Processes)
{
 $a+= $Process.WS
 $b+= $Process.Name
}

$curve = $zgc.GraphPane.AddBar("Test",$null,$a,[System.Drawing.Color]::Red)
$zgc.GraphPane.XAxis.Type = 'Text'
$zgc.GraphPane.XAxis.Scale.FontSpec.Angle = 65
$zgc.GraphPane.XAxis.Scale.MajorStep = 1
$zgc.GraphPane.X2Axis.Scale.FontSpec.Size = 8
$zgc.GraphPane.XAxis.Scale.TextLabels = $b

# Hide the legend
$zgc.GraphPane.Legend.IsVisible = $False

# Make me pretty...
$zgc.GraphPane.Fill = New-Object ZedGraph.Fill([System.Drawing.Color]::WhiteSmoke,[System.Drawing.Color]::Lavender,0)
$zgc.GraphPane.Chart.Fill =  New-Object ZedGraph.Fill([System.Drawing.Color]::FromArgb(255,255,245), [System.Drawing.Color]::FromArgb(255,255,190),90)

# Calculate the Axis Scale Ranges
$zgc.AxisChange()

# Add our graph to the form
$Form.Controls.Add($zgc)
$zgc.dock = [System.Windows.Forms.DockStyle]::Fill

# Show the form
$Form.Add_Shown({$form.Activate()})
[void]$form.showdialog()

The only difference in this example is we create and populate a couple arrays (forgive my naming conventions) and use them as our data points.

I hope I have answered some of the questions about "real" data utilization with ZedGraph.

Enjoy!

PowerShell and ZedGraph – Example 2

If you haven't already, take a look at Example 1 before you move forward!

Let's continuing with our charting example. At this point we have created a simple bar chart. Let's make a couple of modifications.

The first thing we will do is to remove the legend.

All we need to do is set the Legend.IsVisible property:

$zgc.GraphPane.Legend.IsVisible = $False

Next, let's apply some color. We will set the pane background and the Axis background with a gradient:

$zgc.GraphPane.Fill = New-Object ZedGraph.Fill([System.Drawing.Color]::WhiteSmoke,[System.Drawing.Color]::Lavender,0)

$zgc.GraphPane.Chart.Fill = New-Object ZedGraph.Fill([System.Drawing.Color]::FromArgb(255,255,245), [System.Drawing.Color]::FromArgb(255,255,190),90)

Lastly, lets add some text to the graph:

$text = New-Object ZedGraph.TextObj("Supply`nDepleted",5,30)

$zgc.GraphPane.GraphObjList.Add($text)

$arrow = New-Object ZedGraph.ArrowObj([System.Drawing.Color]::Black,10,5,26,5,15)

$zgc.GraphPane.GraphObjList.Add($arrow)

So our end result should look something like this:

The code...

#Load the zedgraph dll
$ZedGraphDll = "C:\zedgraph_dll_v5.1.5\ZedGraph.dll"
[System.Reflection.Assembly]::LoadFrom($ZedGraphDll) | out-null

# Create a WinForm to serve as a container
$global:form = new-object Windows.Forms.form
$form.Size = new-object System.Drawing.Size @(500,400)

# Create a ZedGraphControl
$zgc = new-object -typename ZedGraph.ZedGraphControl
$zgc.GraphPane.Title.Text = "Yuengling Consumption"
$zgc.GraphPane.XAxis.Title.Text = "Month"
$zgc.GraphPane.YAxis.Title.Text = "Bottles"

$xLabels = "April", "May", "June","July", "August"
$yLabels = 60, 60, 75, 70, 15

$zgc.GraphPane.AddBar("Ying",$null,$yLabels,[System.Drawing.Color]::Red)
$zgc.GraphPane.XAxis.Type = 'Text'
$zgc.GraphPane.XAxis.Scale.TextLabels = $xLabels

# Hide the legend
$zgc.GraphPane.Legend.IsVisible = $False

# Fill the pane background with a gradient
$zgc.GraphPane.Fill = New-Object ZedGraph.Fill([System.Drawing.Color]::WhiteSmoke,[System.Drawing.Color]::Lavender,0)

# Fill the Axis Background with a gradient
$zgc.GraphPane.Chart.Fill =  New-Object ZedGraph.Fill([System.Drawing.Color]::FromArgb(255,255,245), [System.Drawing.Color]::FromArgb(255,255,190),90)

# Add text item to decorate the graph
$text = New-Object ZedGraph.TextObj("Supply`nDepleted",5,30)
$zgc.GraphPane.GraphObjList.Add($text)

# Add an arrow pointer for the above text line
$arrow = New-Object ZedGraph.ArrowObj([System.Drawing.Color]::Black,10,5,26,5,15)
$zgc.GraphPane.GraphObjList.Add($arrow)

# Calculate the Axis Scale Ranges
$zgc.AxisChange()

# Add our graph to the form
$Form.Controls.Add($zgc)
$zgc.dock = [System.Windows.Forms.DockStyle]::Fill

# Show the form
$Form.Add_Shown({$form.Activate()}) 
[void]$form.showdialog()

Till next time - Enjoy!