How To : Use Powershell and TFS together

The absolute basics

Where does a newbie to Windows PowerShell start—particularly in regards to TFS? There are a few obvious places. I’m hardly the first person to trip across the natural peanut-butter-and-chocolate nature of TFS and Windows PowerShell together. In fact, the TFS Power Tools contain a set of cmdlets for version control and a few other functions.

Image

There is one issue when downloading them, however. The “typical” installation of the Power Tools leaves out the Windows PowerShell cmdlets! So make sure you choose “custom” and select those Windows PowerShell cmdlets manually.

After they’re installed, you also might need to manually add them to Windows PowerShell before you can start using them. If you try Get-Help for one of the cmdlets and see nothing but an error message, you know you’ll need to do so (and not simply use Update-Help, as the error message implies).

Fortunately, that’s simple. Using the following command will fix the issue:

add-pssnapin Microsoft.TeamFoundation.PowerShell

See the before and after:

Image of command output

A better way to review what’s in the Power Tools and to get the full list of cmdlets installed by the TFS Power Tools is to use:

Get-Command -module Microsoft.TeamFoundation.PowerShell

This method doesn’t depend on the developers including “TFS” in all the cmdlet names. But as it happens, they did follow the Cmdlet Development Guidelines, so both commands return the same results.

Something else I realized when working with the TFS PowerShell cmdlets: for administrative tasks, like those I’m most interested in, you’ll want to launch Windows PowerShell as an administrator. And as long-time Windows PowerShell users already know, if you want to enable the execution of remote scripts, make sure that you set your script execution policy to RemoteSigned. For more information, see How Can I Write and Run a Windows PowerShell Script?.

Of all the cmdlets provided with the TFS Power Tools, one of my personal favorites is Get-TfsServer, which lets me get the instance ID of my server, among other useful things.  My least favorite thing about the cmdlets in the Power Tools? There is little to no useful information for TFS cmdlets in Get-Help. Awkward! (There’s a community bug about this if you want to add your comments or vote on it.)

A different favorite: Get-TFSItemHistory. His following example not only demonstrates the power of the cmdlets, but also some of their limitations:

Get-TfsItemHistory -HistoryItem . -Recurse -Stopafter 5 |

    ForEach-Object { Get-TfsChangeset -ChangesetNumber $_.ChangesetId } |

    Select-Object -ExpandProperty Changes |

    Select-Object -ExpandProperty Item

This snippet gets the last five changesets in or under the current directory, and then it gets the list of files that were changed in those changesets. Sadly, this example also highlights one of the shortcomings of the Power Tools cmdlets: Get-TfsItemHistory cannot be directly piped to Get-TfsChangeset because the former outputs objects with ChangesetId properties, and the latter expects a ChangesetNumber parameter.

One of the nice things is that raw TFS API objects are being returned, and the snap-ins define custom Windows PowerShell formatting rules for these objects. In the previous example, the objects are instances of VersionControl.Client.Item, but the formatting approximates that seen with Get-ChildItem.

So the cmdlets included in the TFS Power Tools are a good place to start if you’re just getting started with TFS and Windows PowerShell, but they’re somewhat limited in scope. Most of them are simply piping results of the tf.exe commands that are already available in TFS. You’ll probably find yourself wanting to do more than just work with these.

 

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