Creating a custom Build.vNext agent

I’m always up for trying new bits of technology. And to be honest, as a consultant I think it’s an absolute necessity to know what is out there. Fortunately, exploring new technologies is fun!

Recently Microsoft has made Build.vNext publicly available on Visual Studio Online. You can read Brian Harry’s blog post here. Build.vNext gives us a much simpler build system than the old Xaml workflow based system. It’s also fully extensible (more about that in a later post) and  fully web-based. Also, the infrastructure has changed: instead of the Build controller – Build agent(s) architecture there is now the concept of build agent pools. These pools can be shared across collections, so you no longer have to deal with a separate controller for each collection.

Visual Studio Online provides a hosted build agent pool. This is great because you don’t have to deal with your own infrastructure. However, if you need to customize your build agent then you’ll have to install your own agent, which you can then connect to VSO.

I thought I’d give that a go and try to build a MVC 5.0 (which is also in preview) app while I’m at it. MVC 5.0 is included with the Visual Studio 2015 preview. In this post I’ll show you how to configure a build agent and connect it to VSO. In a next post, I’ll walk you through the process of creating a vNext build definition for building a MVC 5.0 app.

To get started, we need a server with Visual Studio 2015 RC installed. The fastest way to do that is to get one from Azure. Log in to https://manage.windowsazure.com and create a new virtual machine. There is a template available for the Visual Studio 2015 RC.

In the next couple of screens, choose a username and password for logging on to the machine. The other options can just be left as defaults. Once your machine is completed, connect to it using Remote Desktop.
Once logged in, I want to create a local user for running the build agent under. Go to Server Manager, Tools, Computer Management and open the “Users” node under “Local Users and Computers”. Now right-click and select “New User” and fill in the details.
Now that we have the prerequisites in place, we can get on to the more interesting stuff. First, we have to download the bits for our new build agent. On your new server, open up a browser and log on to your VSO account.  Click the little gear icon on the top-right to go to the VSO Control Panel, then go to the “Agent pools” tab and click the “Download agent” button.
This should give you a zip file which contains everything you need to run a VSO build agent.
Download and extract the zip file to your local machine. I put mine in “C:VsoAgent”.
Now all that we need to do is configure our agent. This is done using PowerShell. Open up a PowerShell window in Administrator mode by shift+right click on the PowerShell icon and selecting “Run as Administrator”.
Then, change to the directory where you downloaded the bits.
Set the execution policy to “Unrestricted” so that you can run the script to configure the agent.
Now, run the configuration script for the agent. It’ll ask you a bunch of questions regarding the configuration of the agent. You can customize if you want to, or just accept the defaults. In my example, I’m configuring the agent to run as a Windows Service so that it will start up when the server starts. Make sure to connect to your VSO account (don’t include the “/DefaultCollection” bit in the URL!) and provide the local account you created to run the agent if you choose to run the agent as a Windows Service. If all goes well, you’ll get a message telling you that the configuration of the agent succeeded.
If you look in the VSO Control Panel, you’ll see your shiny new agent listed, along with it’s capabilities.
 

That’s it! Your build agent is now ready for use. Happy building!