doc(upgrade): document migration steps from hawtio-operator 0.3.0 to …

…0.4.0 #49

README.md

@@ -2,6 +2,10 @@
 
 A [Kubernetes](https://kubernetes.io) operator, based on the [Operator SDK](https://sdk.operatorframework.io), that operates [Hawtio Online](https://github.com/hawtio/hawtio-online).
 
+## Upgrading
+
+See [Upgrading Guide](docs/Upgrading.md) when you are upgrading your hawtio-operator installation.
+
 ## Resources
 
 The `Hawtio` CRD defines the resource the operator uses to configure a Hawtio Online operand, e.g.:

docs/upgrading.md

@@ -0,0 +1,19 @@
+# Hawtio Operator Upgrading Guide
+
+This document describes important changes between hawtio-operator versions and instructions on how to upgrade your operator installation.
+
+- [hawtio-operator 0.4.0](#hawtio-operator-0.4.0)
+
+## hawtio-operator 0.4.0
+
+### `spec.rbac.enabled` field is removed from CRD
+
+From 0.4.0 RBAC support is always enabled, so the field to toggle the feature is removed from the CRD ([#48](https://github.com/hawtio/hawtio-operator/pull/48)). If your `Hawtio` custom resource contains the following field (whether it is `true` or `false`), remove it from the yaml definition.
+
+```yaml
+spec:
+    rbac:
+        enabled: true
+```
+
+If you want to maintain the old `rbac.enabled=false` behaviour, you can still leave it without providing the `hawtio-rbac` ConfigMap which includes `ACL.yaml`. It will be effectively the same as `rbac.enabled=false` in hawtio-operator 0.3.0.