IBM Cloud App Configuration

App Configuration is a centralized feature management and configuration service for use with web and mobile applications, microservices, and distributed environments. You can define feature flags, which are organized into collections and targeted to segments. Change feature flag states in the cloud to activate or deactivate features in your application or environment, often without restarting.

The App Configuration destination helps you toggle the feature flags by leveraging various Event Notifications capabilities. For example, you can use the Periodic Timer source that is provided by Event Notifications to schedule the toggling of feature flags.

Configuring an App Configuration destination

You can configure an App Configuration destination in the Destinations tab.

Before you begin

Before you begin, make sure that you have the following prerequisites in place:

An App Configuration instance with the environments and feature flags created. See Creating an App Configuration instance to learn the process of creating an App Configuration instance.
You need to create a service-to-service authorization between Event Notifications and App Configuration service and assign the role of Config Operator.

Configuration

To configure App Configuration as a destination, complete the following steps:

From your Event Notifications instance, click Destinations.
Click Create to add a new destination.
Enter the following destination details in the Create destination dialog:
- Name: Enter a name for your destination.
- Description: Optionally, enter a description for your destination.
- Type: Under Destination, select App Configuration. Select the account that your App Configuration instance is located in.
  - This account: If your App Configuration instance is in the same account as your Event Notifications instance, select This account. Select the Instance name, Environments, and Feature Flag to be toggled. All three fields must be populated to create the destination.
  - Specific account: If your App Configuration instance and Event Notifications instance are in different accounts, select Specific account. Provide a valid App Configuration instance CRN, select the Environments and Feature Flag to be toggled. All three fields must be populated to create the destination.
Click Create destination.
Click Topics in the Event Notifications instance and click Create. Enter the topic and filter details in the Topic details and Event filters steps, then click Create topic. See Creating an Event Notifications topic for more information.
Proceed to the Subscriptions step. Click Create and enter the following subscription details in the Create subscription dialog:
- Subscription name: Enter a name for the subscription.
- Destination type: Select destination type.
- Destination: Select destination.
- Attributes or Template: When you create the App Configuration subscription, either the attribute or template must be defined. These define the state of the feature flag when a notification is sent.
  - Attributes: You can enable or disable the feature flag when a notification is sent.
  - Template: Define the template under the Templates section of the left navigation pane. See App Configuration Notification Template for more information.
Click Create subscription.

Testing App Configuration destination configuration

You can test an App Configuration destination in the options menu next to the destination. You can test whether the provided configuration is correct with a single click.

Click Destinations in the Event Notifications instance.
On the destination you want to test, click the Options menu and select Test Destination.
Click the Feature Flags tab in your App Configuration instance. If the destination is configured correctly, the feature flag is enabled, which indicates that your destination configuration is successful.

For more information on testing a destination, see Testing Destinations.

App Configuration retry policy

When sending notifications to App Configuration, issues such as network errors and application glitches can cause the requests to fail. Event Notifications automatically retries failed requests to provide resiliency.

For detailed information about retry behavior, including retry attempts, delays, and timeout values, see Retry policy for destinations.