ContentGrid configuration discovery

Dynamic configuration discovery for multi-tenant ContentGrid platform services

Usage

Your application should depend on at least 3 modules:

1. Runtime dependency on the autoconfiguration module: com.contentgrid.configuration:contentgrid-configuration-autoconfigure
2. Runtime dependency on a configuration discovery module (or multiple if discovering from multiple sources)
3. Implementation dependency on one (or more) configuration definitions module

A full configuration is composed from multiple ConfigurationFragments based on their composition key. The way that different fragments are composed into a whole is definition-dependent, but typically lists are merged together. Singular values should typically only be present once, otherwise an arbitrary value is selected.

Configuration discovery modules

Currently, there are 2 different discovery modules available: Kubernetes and Static Spring properties.

Kubernetes discovery module

Module: com.contentgrid.configuration:contentgrid-configuration-kubernetes-fabric8

Uses the fabric8 KubernetesClient to discover configuration from kubernetes secrets and configmaps. Configuration is automatically updated when changes are made in Kubernetes.

This module can be automatically configured when a KubernetesClient bean is available. (e.g. when using spring-cloud-kubernetes)

Property	Type	Description
contentgrid.configuration.discovery.kubernetes.enabled	boolean	Enables configuration discovery through Kubernetes (default true)
contentgrid.configuration.discovery.kubernetes.namespace	string	Sets the kubernetes namespace in which configuration discovery will be done. If unset, defaults to the namespace that the application is deployed in (or default if the application is running outside of Kubernetes)

Other configuration for the Kubernetes client should be done in spring-cloud-kubernetes, or a custom created KubernetesClient.

Static spring properties discovery module

Module: com.contentgrid.configuration:contentgrid-configuration-properties-spring

Reads spring properties underneath contentgrid.configuration.static. These properties are read once on startup and are assumed not to change.

Different sub-properties are available, depending on the chosen configuration definitions modules.

Property	Type	Description
contentgrid.configuration.static.<definition-name>.[config-id].composition-key	string	Composition key to combine multiple configurations
contentgrid.configuration.static.<definition-name>.[config-id].configuration	map<string, string>	Configuration properties

The definition-name is dependent on the configuration definition module. The config-id is an arbitrary, unique identifier of a configuration fragment. This allows partially overriding configurations from different configuration files.

Configuration definitions modules

Currently, there is one configuration definitions module: Contentgrid Apps.

ContentGrid Apps definitions module

Module: com.contentgrid.configuration:contentgrid-configuration-contentgrid-apps

Configuration for ContentGrid Apps.

Configuration key	Type	Description
contentgrid.idp.client-id	string	OIDC client ID for authenticating users to the application
contentgrid.idp.client-secret	string	OIDC client Secret for confidential clients
contentgrid.idp.issuer-uri	uri	OIDC issuer for authenticating users and JWT bearer tokens
contentgrid.routing.domains	list<string>	Comma-separated list of domain names that the application will listen on
contentgrid.cors.origins	list<string>	Comma-separated list of origins that are trusted for CORS for the application

In Kubernetes, the configuration is read from ConfigMap and Service with labels:

• app.contentgrid.com/service-type=gateway
• app.contentgrid.com/application-id

The app.contentgrid.com/application-id label is used as the composition key.

For static configuration, the definition-name is contentgrid-apps.