feat(probes) default to the 3.3 readiness endpoint

Use the 3.3 Kong proxy readiness endpoint by default.

Add instructions for users on older versions.

Release 2.26.

Fix a ToC issue in UPGRADE.md.

charts/kong/CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## Unreleased
+
+### Breaking changes
+
+- The Kong proxy container probe now defaults to `/status/ready` on the status
+  listen. This requires Kong 3.3 or higher. If you wish to continue using an
+  older version and did not have a custom probe configured, you must set the
+  [previous default](https://github.com/Kong/charts/blob/kong-2.25.0/charts/kong/values.yaml#L800-L810)
+  in your values.yaml.
+
 ## 2.25.0
 
 - Generate the `adminApiService.name` value from `.Release.Name` rather than

charts/kong/UPGRADE.md

@@ -17,7 +17,8 @@ upgrading from a previous version.
 ## Table of contents
 
 - [Upgrade considerations for all versions](#upgrade-considerations-for-all-versions)
-- [2.17.0](#2170)
+- [2.26.0](#2260)
+- [2.19.0](#2190)
 - [2.13.0](#2130)
 - [2.8.0](#280)
 - [2.7.0](#270)
@@ -83,6 +84,25 @@ https://raw.githubusercontent.com/Kong/charts/kong-<version>/charts/kong/crds/cu
 For example, if your release is 2.6.4, you would apply
 `https://raw.githubusercontent.com/Kong/charts/kong-2.6.4/charts/kong/crds/custom-resource-definitions.yaml`.
 
+## 2.26.0
+
+2.26 sets the Kong proxy container readiness probe to a new endpoint introduced
+in Kong 3.3. This readiness endpoint reports the container ready when the proxy
+is configured, whereas the earlier endpoint only indicated if the proxy had
+started.
+
+If you have not yet upgraded to Kong 3.3 or higher and do not use a custom
+readiness endpoint, you must set the [previous default](https://github.com/Kong/charts/blob/kong-2.25.0/charts/kong/values.yaml#L800-L810)
+readiness endpoint in your values.yaml:
+
+```
+readinessProbe:
+  httpGet:
+    path: "/status"
+    port: status
+    scheme: HTTP
+```
+
 ## 2.19.0
 
 2.19 sets a default [security context](https://kubernetes.io/docs/tasks/configure-pod-container/security-context/)

charts/kong/values.yaml

@@ -800,7 +800,7 @@ resources: {}
 # readinessProbe for Kong pods
 readinessProbe:
   httpGet:
-    path: "/status"
+    path: "/status/ready"
     port: status
     scheme: HTTP
   initialDelaySeconds: 5