Nathan.Run()

If you’re a fan of the show “Family Guy”, you may remember the joke where Robert Loggia was asked to spell his name. He did so by working his name into a sentence for every letter. For example, “E as in everybody loves Robert Loggia.” We’ve started doing that around the office, with the challenge being can you come up with the verbose spelling fast enough for it to still be relevant. I quickly decided that PowerShell could help me with this. There’s no trick here, really. I break up the incoming text to a character array, and for each letter I reference into a hash table of sentence beginnings to go with each letter.

function Get-VerboseSpelling
{
    Param(
    [string]$Text
    )
    
    $spellingDictionary = @{
    "A"="Awesome,";
    "B"="Boy howdy,";
    "C"="Certainly you now know";
    "D"="Don't you know";
    "E"="Everybody knows";
    "F"="Feel good about yourself because you know";
    "G"="Good thing you now know";
    "H"="Have you heard";
    "I"="I have now told you";
    "J"="Just accept that";
    "K"="Knowledge has been passed because you know that";
    "L"="Look, just accept that";
    "M"="Man, aren't you glad you now know that";
    "N"="Now you know that";
    "O"="Other people know that";
    "P"="Please rember that";
    "Q"="Quick, remember that";
    "R"="Remember that";
    "S"="Stop, collaborate and listen,";
    "T"="Thank you for remembering that";
    "U"="Ultimately, just accept that";
    "V"="Very smart people know that";
    "W"="Why won't you accept that";
    "X"="Xenobiologists know that";
    "Y"="Your significant other already knows that";
    "Z"="Zebras know that";
    }

    $charArray = $Text.ToUpper().ToCharArray();

    foreach($char in $Text.ToUpper().ToCharArray())
    {
        $char = $char.ToString()
        if($char -ne ' ') {
            "{0} as in `"{1} it's {2}`"" -f $char, $spellingDictionary[$char], $Text
        }
    }
}

The real humor here comes when you pair this with the PowerShell Community Extensions’ cmdlet Out-Speech. You can you type something in and have the verbose spelling read to you. The default voice in Windows 7 doesn’t do a particularly good job of it, but it’s still fun.

I’m already seeing ways to improve this, such as having each letter defined with multiple sentence starters where the script will pick one randomly. If you do anything neat to build on this, I’d love to hear about it!

We have been using PowerShell to perform low-friction updates to our intranet application for several months. This lets any of our DevOps staff build an update package, deploy it to the client system and run a single command to update the application. This has worked well for us, until we finally bumped into our first client site that had a web.config file different from the others. In this case, it was the presence of an <identity impersonate=”true” /> tag. After we performed an update at this site, the setting was lost and the application stopped working.

This is clearly not acceptable, but we also do not need to maintain two (or more) copies of a stock config file just to account for a single setting. Fortunately, PowerShell’s powerful handling of XML comes to the rescue. Not only does XML data get treated like an object in PowerShell (so you can do $myXml.ParentNode.ChildNode.AnotherChild), but you have access to all of the XDocument methods you’re used to in C#.

Before performing the update, we want to check the config file for the <identity> tag, and grab a copy of the node. Not the text, but the node itself. This ensures that whatever attributes are defined come with it, without us having to do anything extra. That means that “impersonate=true”, “impersonate=false”, “username=blah”, etc. will all be migrated without having to manually handle each possibility. We then update the web.config file inside of the update package, before deploying it. This ensures that some kind of crash during the update (such as after copying over the new website but before updating the web.config) won’t leave the client’s system in an invalid state. We do this by inserting a copy of the existing <identity> tag.

There is one big gotcha here. When you try to insert a node from one XDocument to another, it complains. The fix for this is to perform an ImportNode() first, then append the node to the new document. Also note that AppendNode() will put the <identity> at the end of <system.web>, not necessarily in the same position it was before. If node order matters for your XML document, be aware of this. If the order of sibling nodes matters for your XML document, I’d argue that you might have a different problem anyway.

After all of that, here’s the code we used. Hopefully it proves useful to someone.

function MigrateIdentityTagsInWebConfig
{
	Param(
		$Source,
		$Destination
	)

	foreach($webConfigFile in (Get-ChildItem -Path $Destination -Filter web.config -Recurse))
	{
		$oldXml = [xml](Get-Content $webConfigFile.FullName)
		$identityElement = $oldXml.configuration."system.web".identity

		#Did we have an identity element in the existing web.config file?
		if($identityElement)
		{
			$correspondingSourceFile = $webConfigFile.FullName.Replace($Destination, $Source)
			$newXml = [xml](Get-Content $correspondingSourceFile)

			#Make a copy of the node from the existing web.config, import it into the new, and then append it
			$newIdentityElement = $newXml.configuration."system.web".OwnerDocument.ImportNode($identityElement, $true)
			[void]$newXml.configuration."system.web".AppendChild($newIdentityElement)

			$newXml.OuterXml | Format-Xml | Set-Content -Path $correspondingSourceFile
		}
	}
}

My employer has a lot of PowerShell v2 scripts in production, spread across a great many servers at a great many sites. It’s because I have to support these scripts in production that I have held off on updating myself to PowerShell v3. I finally got tired of holding myself back and took the plunge. I updated my PowerShell install, but was immediately hit with a wall of red text concerning an incompatibility in my install of PowerShell Community Extensions. No problem, I go and download the latest. Now I can run PowerShell, but I’m smacked in the face with problems from our deployment package scripts. What I really needed to be able to do right away was get back to a v2 compatible mode. Fortunately, that wasn’t too bad.

PowerShell.exe –version 2.0

That will start version 2.0 of PowerShell. As far as I can tell, this isn’t just some compatibility mode, but the real v2 environment (if you know otherwise, let me know in the comments). You can tell there’s a difference by checking the value of $PSVersonTable, or by the difference in behavior in Start-Process. Now I can start up in version 2 and run all of our production scripts in the same environment that (most of) our servers will have.

I’ve had to do this enough now that I just created a new tab type in Console2.

Now when I want to be 100% sure that I’m stuck in PowerShell v2 mode for dealing with production scripts requiring that environment, I can just start up this tab.  It’s clearly labeled via the title, and I selected a fairly irritating cursor style so that there’s never any question what mode I’m running.

All of this is great, except now I get a wall of red text because the new PSCX I just installed doesn’t work with PowerShell v2. Don’t worry, there’s actually a fairly simple solution to that. First, you’re going to want to go grab a version of PSCX that works with PowerShell v2. Install it to a sibling folder of your v3 PSCX install (I picked Modules\Pscx_21).

Most of the time, Import-Module wants the module name and the name of the folder in which it is stored to be the same. The way around this is to point Import-Module to the actual .psd1 file. So Import-Module .\Modules\Pscx_21\Pscx.psd1 works just fine. Now a little bit of trickery with your $profile to figure out what version of PowerShell is being loaded, and to load the correct version of PSCX in response.

if($PSVersionTable.PSVersion.Major –eq 2) {
    Import-Module .\Modules\Pscx_21\Pscx.psd1
}
else {
    Import-Module .\Modules\Pscx
}

Now you will be loading the correct version of PowerShell Community Extensions no matter which version of PowerShell you’re starting. Of course, there are still a few gotchas that we’ve bumped into in our upgrade. I’ll cover those in future posts. What about those of you reading this? Anything you want to warn other developers about before they upgrade to PowerShell version 3?

In a recent upgrade to our product, we discovered that a great many of our custom reports had UniqueName properties that were incompatible with the new version of Telerik’s RadGrid. The question fell to me, “how many reports have spaces in their UniqueName property?” Fortunately, PowerShell made it fairly simple to identify the reports with problems.

Get-ChildItem -Path . -Filter *.aspx -Recurse | 
  Select-String -Pattern "UniqueName=`"\w+\s\w*`"" | 
  Group-Object -Property Path | 
  Select-Object -Property @{Name='Spaces in Name';Expression={$_.Name}}

Wonderful, I have identified the problem. It should come as no surprise to any developer that the next step was “great, can you fix it?” I went through a few files by hand to verify that any kind of mass replace was unlikely to cause issues. Once I was sure it was “safe” (as safe as blindly replacing property values can be), PowerShell made a day-long job take only minutes.

$reports = Get-ChildItem -Path . -Filter *.aspx -Recurse |
    Select-String -Pattern "UniqueName=`"\w+\s\w*`"" |
    Group-Object -Property Path |
    Select-Object -Property Name

foreach($report in $reports)
{
    $aspxPage = $report.Name
    $codeBehind = "{0}.vb" -f, $report.Name

    $uniqueNamesWithSpaces = (Select-String -Path $aspxPage -Pattern `
      "UniqueName=`"(?<uniqueName>\w+\s\w*)`"" `
      | Select-Object -Expand Matches)

    $aspxContent = (Get-Content -Path $aspxPage)
    $codeContent = (Get-Content -Path $codeBehind)

    foreach($uniqueName in $uniqueNamesWithSpaces)
    {
        $aspxContent = $aspxContent -replace `
          $uniqueName.Groups["uniqueName"].Value, `
          $uniqueName.Groups["uniqueName"].Value.Replace(" ", "")

        $codeContent = $codeContent -replace `
          $uniqueName.Groups["uniqueName"].Value, `
          $uniqueName.Groups["uniqueName"].Value.Replace(" ", "")
    }

    Set-Content -Path $aspxPage -Value $aspxContent
    Set-Content -Path $codeBehind -Value $codeContent 
}

And that’s all there is to it. Any custom report that has a RadColumn defined with a UniqueName property containing a space would magically have that space removed, both in the ASPX page and the codebehind file. What about you? How would you have handled this differently? One of the great things about PowerShell is that there’s no One Way to handle everything, so post your solutions below.

This post falls under the heading of things that probably don’t make much sense, except it was fun and I wanted to do something very specific using a very specific technology. Rather than run yet another program in my task tray (which mostly irritates me because of icon clutter and not system resources), how could I just use another tab in my PowerShell window to help me use The Pomodoro Technique? I came up with the following function that I’ve placed in my $profile.

Function Start-Pomodoro
{
    Param (
        [int]$Minutes = 25
    )

    $seconds = $Minutes*60
    $delay = 15 #seconds between ticks

    for($i = $seconds; $i -gt 0; $i = $i - $delay)
    {
        $percentComplete = 100-(($i/$seconds)*100)
        Write-Progress -SecondsRemaining $i `
                       -Activity "Pomodoro" `
                       -Status "Time remaining:" `
                       -PercentComplete $percentComplete
        Start-Sleep -Seconds $delay
    }

   $player = New-Object System.Media.SoundPlayer "C:\Users\me\Dropbox\Music\CTU.wav"
    1..6 | %{ $player.Play() ; sleep -m 1400 }
 }

What does this do? For starters, in my now-dedicated tab, I can just run “Start-Pomodoro” and get a 25-minute timer going, with a progress bar that shows how long I have remaining in my current pomodoro. At the end, it repeats the CTU ringtone from “24″ (which is just irritating enough to get my attention). I had to tinker with the delay on the sleep command so that the clip had time to complete before restarting, so you will need to do the same with whatever audio clip you use.

If using an external audio clip isn’t your speed, you can just use whatever you have for system sounds. Just replace the two audio-playing lines above with something like the following.

1..10 | %{ [System.Media.SystemSounds]::Exclamation.Play() ; sleep -m 750 }

Like I said, I don’t know how useful this is. But it was fun, and I use it pretty much all day.