How-To: Enable preview features

How to specify and enable preview features

Preview features in Dapr are considered experimental when they are first released. These preview features require you to explicitly opt-in to use them. You specify this opt-in in Dapr’s Configuration file.

Preview features are enabled on a per application basis by setting configuration when running an application instance.

Configuration properties

The features section under the Configuration spec contains the following properties:

PropertyTypeDescription
namestringThe name of the preview feature that is enabled/disabled
enabledboolBoolean specifying if the feature is enabled or disabled

Enabling a preview feature

Preview features are specified in the configuration. Here is an example of a full configuration that contains multiple features:

  1. apiVersion: dapr.io/v1alpha1
  2. kind: Configuration
  3. metadata:
  4.   name: featureconfig
  5. spec:
  6.   tracing:
  7.     samplingRate: "1"
  8.     zipkin:
  9.       endpointAddress: "http://zipkin.default.svc.cluster.local:9411/api/v2/spans"
  10.   features:
  11.     - name: Feature1
  12.       enabled: true
  13.     - name: Feature2
  14.       enabled: true

To enable preview features when running Dapr locally, either update the default configuration or specify a separate config file using dapr run.

The default Dapr config is created when you run dapr init, and is located at:

  • Windows: %USERPROFILE%\.dapr\config.yaml
  • Linux/macOS: ~/.dapr/config.yaml

Alternately, you can update preview features on all apps run locally by specifying the --config flag in dapr run and pointing to a separate Dapr config file:

  1. dapr run --app-id myApp --config ./previewConfig.yaml ./app

In Kubernetes mode, the configuration must be provided via a configuration component. Using the same configuration as above, apply it via kubectl:

  1. kubectl apply -f previewConfig.yaml

This configuration component can then be referenced in any application by modifying the application’s configuration to reference that specific configuration component via the dapr.io/config element. For example:

  1. apiVersion: apps/v1
  2. kind: Deployment
  3. metadata:
  4.   name: nodeapp
  5.   labels:
  6.     app: node
  7. spec:
  8.   replicas: 1
  9.   selector:
  10.     matchLabels:
  11.       app: node
  12.   template:
  13.     metadata:
  14.       labels:
  15.         app: node
  16.       annotations:
  17.         dapr.io/enabled: "true"
  18.         dapr.io/app-id: "nodeapp"
  19.         dapr.io/app-port: "3000"
  20.         dapr.io/config: "featureconfig"
  21.     spec:
  22.       containers:
  23.       - name: node
  24.         image: dapriosamples/hello-k8s-node:latest
  25.         ports:
  26.         - containerPort: 3000
  27.         imagePullPolicy: Always

Next steps

Configuration schema

Last modified October 11, 2024: Fixed typo (#4389) (fe17926)