How to install this goddamn extensions?

Hey folks, this will be a really quick post. I've struggling with deploying my ASP.NET Core app via ARM template due to some unexpected problems. Since there's no magic "Enable .NET Core" button in Azure Portal or other App Service property, there's one thing you have to do to make yourself happy. Or maybe two. None is straightforward or intuitive.

Extension

Magically the only thing you need to run ASP.NET Core app in Azure is to install an extension:

Once you have it, your application will run without hesitation. But how to enable it via ARM template?

Use internet

To be honest I got literally no idea how to install an extension with my template. After quick search using Google I found this article. It shows a nice and quick way to deploy an application:

/
{
    "type": "siteextensions",
    "name": "AspNetCoreRuntime",
    "apiVersion": "2015-04-01",
    "location": "[resourceGroup().location]",
    "properties": {
        "version": "[parameters('aspnetcoreVersion')]"
    },
    "dependsOn": [
        "[resourceId('Microsoft.Web/Sites', parameters('siteName'))]"
    ]
}

However - for some reason this advice does not work - while deploying ARM throws an error, that AspNetCoreRuntime extension could not be found. Well, it never rains but it pours.

Use your head

I decided to stop experimenting with different approaches like:

  • using different values of version property
  • using full names as the proper value of name propety
  • installing extension using Powershell where it clearly worked

And made the one, final decision - I'll get rid of version and use(hopefully) the most recent one. Using following template:

/
{
    "type": "siteextensions",
    "name": "AspNetCoreRuntime",
    "apiVersion": "2015-04-01",
    "location": "[resourceGroup().location]",
    "dependsOn": [
        "[resourceId('Microsoft.Web/Sites', parameters('siteName'))]"
    ]
}

ARM had no problems deploying my App Service. 

I'm not sure whether you have to pass a very specific version as a value or maybe this parameter is not supported currently - all in all I was a bit dissapointed, that an article 3 months old seemed to be either outdated or incomplete. This is not how you help your community.