In a Kustomization's post-build substitution sources, introduce a new
"Optional" field to allow referencing a Kubernetes ConfigMap or Secret
that may not exist at time of reconciliation. Treat substitution when
the referenced object is missing as if the object had been present but
empty, lacking any variable bindings.
Retain the longstanding behavior of interpreting references to
Kubernetes objects being mandatory by default, such that
reconciliation fails if such a referenced object does not exist. Only
when the "Optional" field is set to true will reconciliation tolerate
finding the referenced object to be missing.
Signed-off-by: Steven E. Harris <seh@panix.com>
Reconciler behaviour:
- Creates an inventory of objects to be applied (persisted in-cluster under `.status.inventory`).
- Applies first custom resource definitions (CRDs) and namespaces, waits for them to register and only then applies the custom resources.
- Validates all resources with server-side dry-run apply (namespaced objects must contain `metadata.namespace`, defaulting to the `default` namespace is no longer supported).
- Reconciles only the resources that drifted.
- Prunes the objects that were previously applied but are missing from the current inventory.
- Emits events for only the resources that where created, configured or deleted.
Signed-off-by: Stefan Prodan <stefan.prodan@gmail.com>
Steven E. Harris
Stefan Prodan