feat(labels): add gateway.selectorLabels with component label

Add gateway.selectorLabels helper with app.kubernetes.io/component:
gateway, matching the existing dataservice.selectorLabels pattern.
Applied to pod labels and Service selectors (both mutable).

Deployment matchLabels left unchanged to avoid requiring recreation.
Users who want it in matchLabels can use .Values.selectorLabels.

Note: the Service selector now includes component: gateway. During
upgrade from a previous version, old pods lack this label and won't
receive traffic until new pods are ready. Use maxSurge: 100% or
blue-green deploy to avoid downtime on first upgrade.

Author: Campbell Pool

charts/portkey-gateway/templates/_helpers.tpl

@@ -52,12 +52,22 @@ app.kubernetes.io/instance: {{ .Release.Name }}
 {{- end }}
 {{- end }}
 
+{{/*
+Gateway selector labels — adds component label for pod metadata and Service
+selectors. Deployment matchLabels uses portkeyenterprise.selectorLabels
+(without component) to avoid requiring Deployment recreation on upgrade.
+*/}}
+{{- define "gateway.selectorLabels" -}}
+{{ include "portkeyenterprise.selectorLabels" . }}
+app.kubernetes.io/component: gateway
+{{- end }}
+
 {{/*
 Gateway labels
 */}}
 {{- define "gateway.labels" -}}
 {{- include "portkeyenterprise.labels" . | nindent 4 }}
-{{- include "portkeyenterprise.selectorLabels" . | nindent 4 }}
+{{- include "gateway.selectorLabels" . | nindent 4 }}
 {{- end }}
 
 {{/*

charts/portkey-gateway/templates/gateway/service.yaml

@@ -23,7 +23,7 @@ spec:
       name: mcp
     {{- end }}
   selector:
-    {{- include "portkeyenterprise.selectorLabels" . | nindent 4 }}
+    {{- include "gateway.selectorLabels" . | nindent 4 }}
 ---
 {{- if and .Values.mcpService.enabled (eq (include "mcp.enabled" .) "true") }}
 apiVersion: v1
@@ -47,5 +47,5 @@ spec:
       protocol: TCP
       name: mcp
   selector:
-    {{- include "portkeyenterprise.selectorLabels" . | nindent 4 }}
+    {{- include "gateway.selectorLabels" . | nindent 4 }}
 {{- end }}