feat: conditional redis pdb config

Chart.yaml

@@ -2,5 +2,5 @@ apiVersion: v2
 name: pgdog-control
 description: PgDog Control
 type: application
-version: 0.3.2
-appVersion: "f477677f"
+version: 0.3.3
+appVersion: "80895477"

README.md

@@ -71,12 +71,23 @@ redis:
 | Option                    | Description                                                                                                                                         |
 | ------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `redis.enabled`           | Deploy the chart-managed Redis resources (bool, default `true`).                                                                                    |
+| `redis.pdb.enabled`       | Create the Redis PodDisruptionBudget with `minAvailable: 1` (bool, default `true`).                                                                  |
 | `redis.url`               | Redis connection string written to `[redis].url` in `control.toml`. When empty, defaults to the chart-managed Redis Service (string, default `""`). |
 | `redis.image.repository`  | Redis image repository (string, default `redis`).                                                                                                   |
 | `redis.image.tag`         | Redis image tag (string, default `7-alpine`).                                                                                                       |
 | `redis.image.pullPolicy`  | Redis image pull policy (string, default `IfNotPresent`).                                                                                           |
 | `redis.image.pullSecrets` | Image pull secrets attached to the Redis pod (list, default `[]`).                                                                                  |
 
+The Redis PodDisruptionBudget blocks voluntary evictions of the single Redis replica, including during node drains and managed node upgrades. Set `redis.pdb.enabled: false` to allow these evictions while keeping Redis deployed:
+
+```yaml
+redis:
+  pdb:
+    enabled: false
+```
+
+Redis will be unavailable while its pod is replaced. The pod retains its `cluster-autoscaler.kubernetes.io/safe-to-evict: "false"` annotation.
+
 ### Raft
 
 Enable Raft with a top-level setting:

templates/redis-pdb.yaml

@@ -1,4 +1,4 @@
-{{- if .Values.redis.enabled }}
+{{- if and .Values.redis.enabled .Values.redis.pdb.enabled }}
 apiVersion: policy/v1
 kind: PodDisruptionBudget
 metadata:

values.yaml

@@ -197,6 +197,10 @@ redis:
   # Deploy the chart-managed Redis instance. Disable this when using an
   # external Redis and set redis.url to its connection string.
   enabled: true
+  pdb:
+    # Keep at least one Redis pod available. With a single replica, this
+    # blocks node drains; disable to allow Redis to be evicted during maintenance.
+    enabled: true
   # Connection string written to [redis].url in control.toml. When empty,
   # it points to the chart-managed Redis service.
   url: ""