Hot Update of Application Module Properties

This feature is to update the application module properties without a restart of the application.

Hot Update feature can only be used by configuring application with Configuration Management Services on Docker (using Consul and AWS Parameter Store), Kubernetes (using Consul), and Cloud Foundry with Spring Cloud (using Git and Vault as back end). For more information, see Using Configurations from Configuration Management Services for Docker and Using Configurations from Configuration Management Services for Cloud Foundry.

Note: Hot update on Kubernetes ConfigMap is not supported.

Affected areas where the updated properties come in effect at runtime:

The updated properties are affected only in the activity input mapping through:
  • The updated properties are affected only in the activity input mappings through the geModuleProperty() of the x-path function.
  • The process properties mapped to the module properties used as input mappings.

Areas that does not get affected after the update call of application properties:
  • The Shared Resources do not get updated as they keep running with the old application properties.

Behavioral changes during runtime after update call of application properties:

In an application, a number of jobs (process instances) are running in an Appnode. After the update call of application module properties, the already running process instances will continue to run with the old set of the module properties, and the new process instances created after the update will run with the new set of module properties.

Behavioral changes for subprocesses after update call of application properties:

There are two types of subprocesses:
  • Direct subprocesses:
    • Spawned: For spawned subprocesses, the latest set of application properties is used.
    • Non-spawned: The same set of application properties is used as of the parent process.
  • Service-based subprocess: In the service-based subprocess, the parent process waits for a reply from the subprocess, so the same set of properties as the parent is used for the subprocess.

Using Hot Update for Application Module Properties
  • To configure Hot Update, change the properties of the application at the configured Configuration Management Service.
  • Hit a public rest API /bwm/monitor.json/refresh of the container at port 8090.
  • The updated properties from the Configured Management Services will be used to update the application module properties inside the application.