Reconciler Config#
In Choreo, a reconciler configuration is defined within a reconciler resource, where developers specify their specific parameters for their usecase. This configuration determines how the reconciler interacts with the system’s resources.
Name#
Each reconciler should be given a unique name, we recommend using the following convention.
<resource name>.<group>.<unique id>
e.g.
where:
- resource name: helloworlds
- group: example.com
- unique id: hello-world
changing the name of a reconciler once it has executed it business logic can lead to conflicting information, If you have to do so remove the db folder from your environment
Condition#
Conditions are used to reflect the status of the reconcilation. Given we can have multiple reconcilers on a primary resource, each doing a specific thing, conditions need to be uniquely identified through a conditionType.
Conditions are identified using the following parameters, However as a developer the only thing you have to worry about is uniqueness of a conditionType within a given resource for a given resonciler.
conditions:
- lastTransitionTime: "2024-11-12T11:01:36Z"
message: ""
reason: Ready
status: "True"
type: IPClaimReady
changing the conditionType of a reconciler once it has executed it business logic can lead to conflicting information, If you have to do so remove the db folder from your environment
For Resource hook#
The for resource hook is mandatory and identifies the primary resource that the reconciler manages. It is sometimes referred to as the primary resource. A For resource is mandatory in a reconciler config
for:
group: nf.nephio.org
version: v1alpha1
kind: NFDeployment
selector:
match:
spec.provider: upf.free5gc.io
Parameters:
- GVK (Group, Version, Kind): Identifies the for resource.
- Filters: Specify criteria to select specific resources for reconciliation. These filters use the CEL (Common Expression Language) functionality, allowing for complex logic across all resource fields, including lists and maps. Filters operate under a default-deny policy and require explicit whitelisting.
Watch resource hook#
The watch resource hook is optional and used when a reconciler depends on external data or other resources for its logic. Changes in any watched resources specified in the reconciler configuration will trigger the reconciliation process for the associated primary resource.
watches:
- group: req.nephio.org
version: v1alpha1
kind: Capacity
selector:
match:
metadata.name: upf
Parameters:
- GVK (Group, Version, Kind): Identifies the watch resource.
- Filters: Optional criteria to identify specific attributes that trigger the reconciliation process. These also operate under a default-deny policy and require whitelisting.
Own resource hook#
Reconcilers may define own resources—those they create, update, or delete as a result of their business logic. These resources are often referred to as child resources.
Parameters:
• GVK (Group, Version, Kind): Identifies the own resource.
When the business logic creates child resources it uses owner referernces and finalizers parameters on the child resources: - Owner References are used to track resources created by the reconciler, ensuring that dependency relationships are maintained. - Finalizers are used to allow the reconciler to perform necessary clean-up tasks before the child resource is fully removed from the system.
Filtering mechanisms are omitted for owneed resources given there is an explicit parent relationship using owner references.
Reconciler config example#
Below is a practical example of how to define a reconciler configuration in Choreo. This configuration specifies how the reconciler interacts with various resources, utilizing the for, owns, and watches clauses to manage relationships and dependencies effectively.
apiVersion: choreo.kform.dev/v1alpha1
kind: Reconciler
metadata:
name: nodes.infra.kuid.dev.itfce
spec:
conditionType: InterfaceReady
for:
group: infra.kuid.dev
version: v1alpha1
kind: Node
selector:
match:
status.conditions.exists(c, c.type == 'IPClaimReady' && c.status == 'True'): "true"
owns:
- group: device.network.kubenet.dev
version: v1alpha1
kind: Interface
- group: device.network.kubenet.dev
version: v1alpha1
kind: SubInterface
watches:
- group: ipam.be.kuid.dev
version: v1alpha1
kind: IPIndex
selector:
match:
metadata.name: kubenet.default
status.conditions.exists(c, c.type == 'Ready' && c.status == 'True'): "true"
Filtering example using cel expressions#
This example shows how to match on a resource only when the conditionType == Ready and the status == True