Enabling Steeltoe apps for Application Live View

This topic for developers tells you how to extend .NET Core Apps to Steeltoe apps and enable Application Live View on Steeltoe workloads within Tanzu Application Platform (commonly known as TAP).

Application Live View supports Steeltoe .NET apps with .NET core runtime version v6.0.8.

Extend .NET Core Apps to Steeltoe Apps

A .NET Core application can be extended to a Steeltoe application by adding independent NuGet packages.

To enable the Actuators on a .NET Core App:

1. Add a PackageReference to your .csproj file:

   <PackageReference Include="Steeltoe.Management.EndpointCore" Version="$(SteeltoeVersion)" />
   

   Note

   The PackageReference is expected to change to Steeltoe.Management.Endpoint from version Steeltoe 4.0 onwards.

2. Call the extension AddAllActuators in your Program.cs file:

   builder.WebHost.AddAllActuators();
   

3. (Optional) You can add app-specific configurations, such as the following.

   To expose all management actuator endpoints except env endpoint, add the following configuration to your appsettings.json file:

   {
     "Management": {
       "Endpoints": {
         "Actuator":{
           "Exposure": {
             "Include": [ "*" ],
             "Exclude": [ "env" ]
           }
         }
       }
     }
   }
   

   To enable logging, add the following configuration to your appsettings.json file:

   {
     "Logging": {
       "LogLevel": {
         "Default": "Information",
         "Microsoft": "Warning",
         "Steeltoe": "Warning",
         "Sample": "Information"
       }
     }
   }
   

   To enable heapdump, add the following configuration to your appsettings.json file:

   {
     "Management": {
       "Endpoints": {
         "HeapDump": {
           "HeapDumpType": "Normal"
         }
       }
     }
   }
   

Enable Application Live View on Steeltoe Tanzu Application Platform workload

You can enable Application Live View to interact with a Steeltoe app within Tanzu Application Platform.

To enable Application Live View on the Steeltoe Tanzu Application Platform workload, the Application Live View convention service automatically applies labels on the workload, such as tanzu.app.live.view.application.flavours: steeltoe and tanzu.app.live.view: true, based on the Steeltoe image metadata.

Here’s an example of creating a workload for a Steeltoe Application:

tanzu apps workload create steeltoe-app --type web --git-repo https://github.com/vmware-tanzu/application-accelerator-samples --sub-path weatherforecast-steeltoe --git-branch main --annotation autoscaling.knative.dev/min-scale=1 --yes --label app.kubernetes.io/part-of=sample-app

If your application image is NOT built with Tanzu Build Service, to enable Application Live View on Steeltoe Tanzu Application Platform workload, use the following command. For example:

tanzu apps workload create steeltoe-app --type web --app steeltoe-app --image IMAGE-NAME --annotation autoscaling.knative.dev/min-scale=1 --yes --label tanzu.app.live.view=true --label tanzu.app.live.view.application.name=steeltoe-app --label tanzu.app.live.view.application.flavours=steeltoe

Where IMAGE-NAME is the name of your application image.

Note

Thread metrics is available in SteeltoeVersion 3.2.*. To enable the Threads page in the Application Live View UI, add the following configuration to your .csproj file:

<PropertyGroup>
    <SteeltoeVersion>3.2.*</SteeltoeVersion>
</PropertyGroup>