fix(helm): add backward compatibility for legacy persistence configs

- Add helper functions to detect and use legacy persistence configs
- Legacy auth.multiUserBasic.persistence.* and qdrant.localPersistence.*
  configs continue to work but show deprecation warnings in NOTES.txt
- New dataStorage.enabled takes precedence when explicitly set
- PVC size/accessMode/storageClass values from legacy configs are honored

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

charts/nextcloud-mcp-server/templates/NOTES.txt

@@ -120,6 +120,55 @@ Your Nextcloud MCP Server has been deployed in {{ .Values.auth.mode }} authentic
    The dashboard JSON is available in the chart at charts/nextcloud-mcp-server/dashboards/nextcloud-mcp-server.json
 {{- end }}
 
+{{- $legacyMultiUserBasic := eq (include "nextcloud-mcp-server.legacyMultiUserBasicPersistence" .) "true" }}
+{{- $legacyQdrant := eq (include "nextcloud-mcp-server.legacyQdrantPersistence" .) "true" }}
+{{- if or $legacyMultiUserBasic $legacyQdrant }}
+
+================================================================================
+                         DEPRECATION WARNING
+================================================================================
+
+You are using deprecated persistence configuration that will be removed in a
+future release. Your deployment will continue to work, but please migrate to
+the new unified dataStorage configuration.
+
+Deprecated settings detected:
+{{- if $legacyMultiUserBasic }}
+  - auth.multiUserBasic.persistence.* (currently enabled)
+{{- end }}
+{{- if $legacyQdrant }}
+  - qdrant.localPersistence.* (currently enabled)
+{{- end }}
+
+To migrate, update your values.yaml:
+
+  dataStorage:
+    enabled: true
+{{- if $legacyMultiUserBasic }}
+    size: {{ .Values.auth.multiUserBasic.persistence.size }}
+{{- else if $legacyQdrant }}
+    size: {{ .Values.qdrant.localPersistence.size }}
+{{- end }}
+    # storageClass: ""  # Optional: specify storage class
+    # existingClaim: "" # Optional: use existing PVC to preserve data
+
+After migrating, remove the deprecated settings:
+{{- if $legacyMultiUserBasic }}
+  - auth.multiUserBasic.persistence.enabled
+  - auth.multiUserBasic.persistence.size
+  - auth.multiUserBasic.persistence.storageClass
+  - auth.multiUserBasic.persistence.accessMode
+{{- end }}
+{{- if $legacyQdrant }}
+  - qdrant.localPersistence.enabled
+  - qdrant.localPersistence.size
+  - qdrant.localPersistence.storageClass
+  - qdrant.localPersistence.accessMode
+{{- end }}
+
+================================================================================
+{{- end }}
+
 For more information and documentation:
 - GitHub: https://github.com/cbcoutinho/nextcloud-mcp-server
 - Documentation: https://github.com/cbcoutinho/nextcloud-mcp-server#readme

charts/nextcloud-mcp-server/templates/_helpers.tpl

@@ -138,6 +138,44 @@ Create the name of the PVC to use for /app/data storage
 {{- end }}
 {{- end }}
 
+{{/*
+Determine if data storage PVC should be enabled (backward compatible)
+Checks new dataStorage.enabled OR legacy persistence configs
+*/}}
+{{- define "nextcloud-mcp-server.dataStorageEnabled" -}}
+{{- if .Values.dataStorage.enabled -}}
+true
+{{- else if and (eq .Values.auth.mode "multi-user-basic") .Values.auth.multiUserBasic.enableOfflineAccess .Values.auth.multiUserBasic.persistence.enabled -}}
+true
+{{- else if and (eq .Values.qdrant.mode "persistent") .Values.qdrant.localPersistence.enabled -}}
+true
+{{- else -}}
+false
+{{- end -}}
+{{- end }}
+
+{{/*
+Check if legacy multi-user-basic persistence config is being used
+*/}}
+{{- define "nextcloud-mcp-server.legacyMultiUserBasicPersistence" -}}
+{{- if and (eq .Values.auth.mode "multi-user-basic") .Values.auth.multiUserBasic.enableOfflineAccess .Values.auth.multiUserBasic.persistence.enabled (not .Values.dataStorage.enabled) -}}
+true
+{{- else -}}
+false
+{{- end -}}
+{{- end }}
+
+{{/*
+Check if legacy qdrant persistence config is being used
+*/}}
+{{- define "nextcloud-mcp-server.legacyQdrantPersistence" -}}
+{{- if and (eq .Values.qdrant.mode "persistent") .Values.qdrant.localPersistence.enabled (not .Values.dataStorage.enabled) -}}
+true
+{{- else -}}
+false
+{{- end -}}
+{{- end }}
+
 {{/*
 Return the MCP server port
 */}}

charts/nextcloud-mcp-server/templates/deployment.yaml

@@ -300,7 +300,7 @@ spec:
             claimName: {{ include "nextcloud-mcp-server.oauthPvcName" . }}
         {{- end }}
         - name: data-storage
-        {{- if .Values.dataStorage.enabled }}
+        {{- if eq (include "nextcloud-mcp-server.dataStorageEnabled" .) "true" }}
           persistentVolumeClaim:
             claimName: {{ include "nextcloud-mcp-server.dataStoragePvcName" . }}
         {{- else }}

charts/nextcloud-mcp-server/templates/pvc.yaml

@@ -16,7 +16,21 @@ spec:
       storage: {{ .Values.auth.oauth.persistence.size }}
 {{- end }}
 ---
-{{- if and .Values.dataStorage.enabled (not .Values.dataStorage.existingClaim) }}
+{{- if and (eq (include "nextcloud-mcp-server.dataStorageEnabled" .) "true") (not .Values.dataStorage.existingClaim) }}
+{{- $legacyMultiUserBasic := eq (include "nextcloud-mcp-server.legacyMultiUserBasicPersistence" .) "true" }}
+{{- $legacyQdrant := eq (include "nextcloud-mcp-server.legacyQdrantPersistence" .) "true" }}
+{{- $accessMode := .Values.dataStorage.accessMode }}
+{{- $storageClass := .Values.dataStorage.storageClass }}
+{{- $size := .Values.dataStorage.size }}
+{{- if $legacyMultiUserBasic }}
+{{- $accessMode = .Values.auth.multiUserBasic.persistence.accessMode }}
+{{- $storageClass = .Values.auth.multiUserBasic.persistence.storageClass }}
+{{- $size = .Values.auth.multiUserBasic.persistence.size }}
+{{- else if $legacyQdrant }}
+{{- $accessMode = .Values.qdrant.localPersistence.accessMode }}
+{{- $storageClass = .Values.qdrant.localPersistence.storageClass }}
+{{- $size = .Values.qdrant.localPersistence.size }}
+{{- end }}
 apiVersion: v1
 kind: PersistentVolumeClaim
 metadata:
@@ -25,11 +39,11 @@ metadata:
     {{- include "nextcloud-mcp-server.labels" . | nindent 4 }}
 spec:
   accessModes:
-    - {{ .Values.dataStorage.accessMode }}
-  {{- if .Values.dataStorage.storageClass }}
-  storageClassName: {{ .Values.dataStorage.storageClass }}
+    - {{ $accessMode }}
+  {{- if $storageClass }}
+  storageClassName: {{ $storageClass }}
   {{- end }}
   resources:
     requests:
-      storage: {{ .Values.dataStorage.size }}
+      storage: {{ $size }}
 {{- end }}