Customization

This page will describe how you can customize your Keycloak instance.

Themes, providers and custom files

VSHNKeycloak allows you to use custom providers, themes and files. Create a custom container image and use it to customize your Keycloak instance as described below.

Example to create a Keycloak instance an image containing custom themes and providers
apiVersion: vshn.appcat.vshn.io/v1
kind: VSHNKeycloak
metadata:
  name: keycloak-app1-prod
  namespace: prod-app
spec:
  parameters:
    service:
      version: "26"
      customizationImage:
        image: https://registry/user/image:tag (1)
        imagePullSecretRef:
          name: secret-name (2)
          namespace: secret-namespace (3)
      customFiles:
        - source: path/in/customization/image (4)
          destination: path/in/keycloak/instance (5)
    size:
      plan: standard-2
  writeConnectionSecretToRef:
    name: keycloak-creds
1 Container image url
2 Secret name containing credentials for the registry
3 Secret namespace
4 File in your customization image (can also be a folder)
5 Destination path in Keycloak instance, relative to /opt/keycloak
Themes and providers will be implicitly copied if found in your image. You do not need to add them separately in customFiles.

Configuration

You can provide a custom configuration to Keycloak using a ConfigMap. The content of the ConfigMap is a JSON file based on the Keycloak export files. You can logically separate different configurations inside the ConfigMap by using different keys. However, each key must end in .json.

Changes in the underlying ConfigMap or Secret referenced by customConfigurationRef or customEnvVariablesRef will trigger an external Job to configure the Keycloak instance via its API. The configuration will be applied dynamically and loaded into the database without requiring a restart of the Keycloak instance. To speed up the propagation of changes, refer to the section Propagating Changes to Referenced Resources.

An extensive set of configuration examples can be found here.

The configuration also supports variable substitution.

Variables exposed by Spring Boot (through configtree or external configuration) can be accessed by $(property.name)

In additional, the string substitution support multiple prefixes for different approaches:

Base64 Decoder:        $(base64Decoder:SGVsbG9Xb3JsZCE=)
Base64 Encoder:        $(base64Encoder:HelloWorld!)
Java Constant:         $(const:java.awt.event.KeyEvent.VK_ESCAPE)
Date:                  $(date:yyyy-MM-dd)
DNS:                   $(dns:address|apache.org)
Environment Variable:  $(env:USERNAME)
File Content:          $(file:UTF-8:src/test/resources/document.properties)
Java:                  $(java:version)
Localhost:             $(localhost:canonical-name)
Properties File:       $(properties:src/test/resources/document.properties::mykey)
Resource Bundle:       $(resourceBundle:org.example.testResourceBundleLookup:mykey)
Script:                $(script:javascript:3 + 4)
System Property:       $(sys:user.dir)
URL Decoder:           $(urlDecoder:Hello%20World%21)
URL Encoder:           $(urlEncoder:Hello World!)
URL Content (HTTP):    $(url:UTF-8:http://www.apache.org)
URL Content (HTTPS):   $(url:UTF-8:https://www.apache.org)
URL Content (File):    $(url:UTF-8:file:///$(sys:user.dir)/src/test/resources/document.properties)
XML XPath:             $(xml:src/test/resources/document.xml:/root/path/to/node)

Example

The following example demonstrates how a custom configuration that creates a new realm looks like:

Configmap definition for a custom realm to be created when starting up keycloak.
apiVersion: v1
kind: ConfigMap
metadata:
  name: keycloak-app1-prod-config
  namespace: prod-app
data:
  keycloak-config.json: |
    {
      "enabled": true,
      "realm": "prod-app"
    }
Keycloak instance with custom configuration
apiVersion: vshn.appcat.vshn.io/v1
kind: VSHNKeycloak
metadata:
  name: keycloak-app1-prod
  namespace: prod-app
spec:
  parameters:
    service:
      customConfigurationRef: keycloak-app1-prod-config (1)
1 The name of the ConfigMap. Must be in the same namespace as the Keycloak claim.

Environment variables

You can pass custom environment variables to your Keycloak instance. These variables can be used by your custom providers or custom configuration.

The customEnvVariablesRef parameter has been deprecated in favor of the new envFrom parameter. While customEnvVariablesRef is still supported for backward compatibility, it is recommended to use envFrom for defining environment variables, as it allows specifying multiple sources, including both ConfigMap and Secret.

Using envFrom

The envFrom parameter allows you to define multiple sources for environment variables. Each source can be a ConfigMap or a Secret.

Example

Keycloak instance with envFrom using multiple sources
apiVersion: vshn.appcat.vshn.io/v1
kind: VSHNKeycloak
metadata:
  name: keycloak-app-envfrom
  namespace: prod-app
spec:
  parameters:
    service:
      envFrom:
        - configMapRef:
            name: env-from-cm (1)
        - secretRef:
            name: env-from-secret (2)
1 Reference to a ConfigMap containing environment variables.
2 Reference to a Secret containing environment variables.

Each referenced ConfigMap or Secret must be in the same namespace as the Keycloak claim.

Using customEnvVariablesRef (Deprecated)

The customEnvVariablesRef parameter allows you to reference a single Secret containing environment variables. While this method is deprecated, it is still supported for backward compatibility.

Example

Secret containing a custom environment variable
apiVersion: v1
kind: Secret
metadata:
  name: keycloak-app2-prod-env
  namespace: prod-app
stringData:
  REALM_NAME: prod-app
type: Opaque
Configmap definition referencing an environmental variable
apiVersion: v1
kind: ConfigMap
metadata:
  name: keycloak-app2-prod-config
  namespace: prod-app
data:
  keycloak-config.json: |
    {
      "enabled": true,
      "$(env:REALM_NAME)"
    }
Keycloak instance with custom configuration and environment variables
apiVersion: vshn.appcat.vshn.io/v1
kind: VSHNKeycloak
metadata:
  name: keycloak-app2-prod
  namespace: prod-app
spec:
  parameters:
    service:
      customConfigurationRef: keycloak-app2-prod-config (1)
      customEnvVariablesRef: keycloak-app2-prod-env (2)
1 The name of the ConfigMap. Must be in the same namespace as the Keycloak claim.
2 The name of the Secret that contains the environment variables. Must be in the same namespace as the Keycloak claim.

Custom Mounts

You can mount additional Kubernetes Secrets and ConfigMaps directly into the Keycloak container’s filesystem by using the customMounts parameter under spec.parameters.service.

Specifying custom mounts in your Keycloak instance
apiVersion: vshn.appcat.vshn.io/v1
kind: VSHNKeycloak
metadata:
  name: keycloak-app3-prod
  namespace: prod-app
spec:
  parameters:
    service:
      customMounts:
        - name: custom-secret1
          type: secret
        - name: custom-secret2
          type: secret
        - name: custom-configmap
          type: configMap

By default, mounts follow this folder structure:

  • Secrets (type: secret) are mounted under /custom/secrets/{name}/…​

  • ConfigMaps (type: configMap) are mounted under /custom/configs/{name}/…​

For example, a Secret named custom-secret1 will be available under /custom/secrets/custom-secret1/, and a ConfigMap named custom-configmap under /custom/configs/custom-configmap/. Mount names must be unique within the customMounts list to avoid folder name collisions inside the container.

Propagating Changes to Referenced Resources

When you make changes to a ConfigMap or Secret that is referenced by your VSHNKeycloak instance (e.g., via customConfigurationRef, customEnvVariablesRef or customMounts), these changes are not immediately propagated to the running Keycloak instance.

To force a reconciliation and apply the updated configuration or environment variables, you need to annotate the VSHNKeycloak resource. This tells Crossplane to re-evaluate the resource and apply any changes from its external references.

Manually triggering a reconciliation
kubectl annotate vshnkeycloak [NAME] -n [NAMESPACE] crossplane.io/touch="$(date +%s)" --overwrite

Replace [NAME] with the name of your VSHNKeycloak instance (e.g., keycloak-app1-prod or keycloak-app2-prod), and [NAMESPACE] with the namespace where the claim was created.