feat(helm): add snapshot functionality with automatic cleanup

- Add snapshot configuration section to values.yaml with:
  - Enable/disable toggle
  - Cron schedule configuration
  - Format selection (dragonfly/rdb)
  - Cleaner settings (image, interval, max count, resources)

- Add snapshot-cleaner sidecar container to pod template:
  - Automatically removes old snapshots based on max_count
  - Supports both dragonfly (.dfs) and rdb formats
  - Configurable cleanup interval and resource limits

- Add snapshot cron arguments to main dragonfly container
- Maintains backward compatibility with existing configurations

Author: renan

contrib/charts/dragonfly/templates/_pod.tpl

@@ -83,6 +83,13 @@ containers:
     {{- end }}
     args:
       - "--alsologtostderr"
+      {{- if .Values.snapshot.enabled }}
+      - "--snapshot_cron"
+      - "{{ .Values.snapshot.schedule }}"
+      {{- if eq .Values.snapshot.format "rdb" }}
+      - "--nodf_snapshot_format"
+      {{- end }}
+      {{- end }}
     {{- with .Values.extraArgs }}
       {{- toYaml . | trim | nindent 6 }}
     {{- end }}
@@ -123,6 +130,31 @@ containers:
     envFrom:
       {{- toYaml . | trim | nindent 6 }}
     {{- end }}
+  {{- if .Values.snapshot.enabled }}
+  - name: snapshot-cleaner
+    image: {{ .Values.snapshot.cleaner.image }}
+    command:
+      - /bin/sh
+      - -c
+      - |
+        while true; do
+          {{- if eq .Values.snapshot.format "dragonfly" }}
+          # Keep only the last {{ .Values.snapshot.cleaner.max_count }} snapshots (composed of two files each)
+          ls -1t /data/dump-*.dfs | tail -n +{{ add 1 (mul .Values.snapshot.cleaner.max_count 2) }} | xargs rm -f
+          {{- else }}
+          # Keep only the last {{ .Values.snapshot.cleaner.max_count }} snapshots
+          ls -1t /data/dump-*.rdb | tail -n +{{ add 1 .Values.snapshot.cleaner.max_count }} | xargs rm -f
+          {{- end }}
+          sleep {{ .Values.snapshot.cleaner.interval }}
+        done
+    volumeMounts:
+      - mountPath: /data
+        name: "{{ .Release.Name }}-data"
+    {{- with .Values.snapshot.cleaner.resources }}
+    resources:
+      {{- toYaml . | trim | nindent 6 }}
+    {{- end }}
+  {{- end }}
 
 {{- if or (.Values.tls.enabled) (.Values.extraVolumes) }}
 volumes:

contrib/charts/dragonfly/values.yaml

@@ -98,6 +98,32 @@ storage:
   # -- Volume size to request for the PVC
   requests: 128Mi
 
+snapshot:
+  # -- enable snapshot
+  enabled: false
+  # -- snapshot cron schedule format (crontab style)
+  schedule: ""
+  # -- snapshot format (default: "df" for Dragonfly, "rdb" is also supported)
+  format: "df"
+  # -- snapshot cleaner
+  cleaner:
+    # -- snapshot cleaner image
+    image: "alpine:3.22"
+    # -- snapshot cleaner interval
+    interval: 30m
+    # -- max snapshots to keep (default: 10)
+    max_count: 10
+    # -- snapshot cleaner resources
+    resources:
+      # -- The requested resources for the cleaner container
+      requests: {}
+      #   cpu: 50m
+      #   memory: 128Mi
+      # -- The resource limits for the cleaner container
+      limits: {}
+      #   cpu: 50m
+      #   memory: 128Mi
+
 tls:
   # -- enable TLS
   enabled: false