Compute memory/ephemeral-storage limits from requests, drop default CPU limits

Every chart now renders its container resources through a duplicated
_helpers.tpl helper (reference implementation in template-chart): requests
ship as chart defaults, missing memory and ephemeral-storage limits are
computed as resources.limitFactor x the request (default 3, satisfactory
keeps 2 to preserve its previously published 8Gi limit), an explicitly set
limit always wins, and a CPU limit is only rendered when set explicitly.
Fixed limit defaults are removed from all values.yaml files; teamspeak-server
gains a values-driven resources block instead of hardcoded template values.
Major version bump for all published charts.

voucher-vault/Chart.yaml

@@ -4,7 +4,7 @@ description: A Helm chart to deploy VoucherVault on Kubernetes
 
 type: application
 
-version: 2.0.0+up1.27.4
+version: 3.0.0+up1.27.4
 appVersion: "1.27.4"
 
 maintainers:

voucher-vault/templates/_helpers.tpl

@@ -0,0 +1,85 @@
+{{/*
+Render the body of a container "resources:" block from a values dict of the form
+
+  resources:
+    limitFactor: 3          # optional, default 3
+    requests: { cpu, memory, ephemeral-storage / ephemeralStorage, ... }
+    limits:   { ... }       # optional, every entry optional
+
+Rules (variant B, see issue #19):
+  - requests are rendered as given (camelCase "ephemeralStorage" is normalized
+    to the Kubernetes key "ephemeral-storage").
+  - an explicitly set limit always wins.
+  - a missing memory / ephemeral-storage limit is computed as
+    limitFactor x the corresponding request.
+  - a missing cpu limit is NOT set at all (the kubelet then treats CPU as
+    unlimited; CPU is compressible, so this cannot kill the workload).
+
+Usage (the values path to the resources dict varies per chart):
+  resources:
+    {{- include "voucher-vault.resources" .Values.<app>.resources | nindent 12 }}
+
+NOTE: charts in this repo deliberately have no dependencies, so this helper is
+duplicated into every chart's templates/_helpers.tpl with the chart's name as
+define prefix. This file in template-chart is the reference implementation.
+*/}}
+{{- define "voucher-vault.resources" -}}
+{{- $resources := . | default dict -}}
+{{- $factor := 3.0 -}}
+{{- if not (kindIs "invalid" $resources.limitFactor) -}}
+{{- $factor = float64 $resources.limitFactor -}}
+{{- end -}}
+{{- $requests := dict -}}
+{{- range $key, $value := ($resources.requests | default dict) -}}
+{{- if not (kindIs "invalid" $value) -}}
+{{- $_ := set $requests (include "voucher-vault.resourceKey" $key) $value -}}
+{{- end -}}
+{{- end -}}
+{{- $limits := dict -}}
+{{- range $key, $value := ($resources.limits | default dict) -}}
+{{- if not (kindIs "invalid" $value) -}}
+{{- $_ := set $limits (include "voucher-vault.resourceKey" $key) $value -}}
+{{- end -}}
+{{- end -}}
+{{- range $key, $request := $requests -}}
+{{- if and (ne $key "cpu") (not (hasKey $limits $key)) -}}
+{{- $_ := set $limits $key (include "voucher-vault.multiplyQuantity" (dict "quantity" $request "factor" $factor)) -}}
+{{- end -}}
+{{- end -}}
+{{- $out := dict -}}
+{{- with $requests }}{{- $_ := set $out "requests" . }}{{- end -}}
+{{- with $limits }}{{- $_ := set $out "limits" . }}{{- end -}}
+{{- toYaml $out -}}
+{{- end -}}
+
+{{/*
+Normalize a resource name from values to its Kubernetes key.
+*/}}
+{{- define "voucher-vault.resourceKey" -}}
+{{- if eq . "ephemeralStorage" -}}ephemeral-storage{{- else -}}{{ . }}{{- end -}}
+{{- end -}}
+
+{{/*
+Multiply a Kubernetes quantity by a factor, keeping its suffix.
+Input: dict "quantity" <string|number> "factor" <float64>.
+Handles plain numbers ("2", "0.5", 1073741824), decimal ("1.5Gi"), binary
+("512Mi", "1Gi", "10Ki") and milli/SI suffixes ("100m", "500M"). Integer
+results are printed without a decimal point.
+*/}}
+{{- define "voucher-vault.multiplyQuantity" -}}
+{{- $quantity := printf "%v" .quantity -}}
+{{- $number := regexFind "^[0-9]+(\\.[0-9]+)?" $quantity -}}
+{{- if not $number -}}
+{{- fail (printf "cannot parse resource quantity %q" $quantity) -}}
+{{- end -}}
+{{- $suffix := trimPrefix $number $quantity -}}
+{{- if not (regexMatch "^(m|k|M|G|T|P|E|Ki|Mi|Gi|Ti|Pi|Ei)?$" $suffix) -}}
+{{- fail (printf "unsupported resource quantity suffix %q in %q" $suffix $quantity) -}}
+{{- end -}}
+{{- $product := mulf (float64 $number) .factor -}}
+{{- if eq $product (floor $product) -}}
+{{- printf "%d%s" (int64 $product) $suffix -}}
+{{- else -}}
+{{- printf "%v%s" $product $suffix -}}
+{{- end -}}
+{{- end -}}

voucher-vault/templates/voucher-vault.sfs.yaml

@@ -59,7 +59,7 @@ spec:
             {{- toYaml .Values.voucherVault.startupProbe | nindent 12 }}
           {{- end }}
           resources:
-            {{- toYaml .Values.voucherVault.resources | nindent 12 }}
+            {{- include "voucher-vault.resources" .Values.voucherVault.resources | nindent 12 }}
           securityContext:
             {{- toYaml .Values.voucherVault.securityContext.container | nindent 12 }}
           volumeMounts:

voucher-vault/values.yaml

@@ -5,14 +5,14 @@ secrets:
 
 voucherVault:
   resources:
+    # Limits are optional: memory and ephemeral-storage limits default to
+    # limitFactor x the request, an explicitly set limit always wins, and a
+    # CPU limit is only set when configured explicitly under "limits".
+    limitFactor: 3
     requests:
       cpu: 0.1
       memory: 256Mi
       ephemeral-storage: 10Mi
-    limits:
-      cpu: 1
-      memory: 384Mi
-      ephemeral-storage: 100Mi
   # "/" answers with a redirect for anonymous users, which httpGet treats as
   # success. The Host header must be set to 127.0.0.1 because Django's
   # ALLOWED_HOSTS only accepts 127.0.0.1 and the configured DOMAIN — probing