satisfactory: strict values.schema.json and null-safe hardening

No ingress gate: this chart has no Ingress at all (game and messaging
ports are exposed via NodePort), and ingress.domain appears neither in
its templates nor in its values.

1. values.schema.json (#68): additionalProperties: false on every
   chart-owned object level. Like teamspeak-server, this chart keeps env,
   probes and securityContext at the TOP level, and the schema mirrors
   that shape.

2. Null-safety for hardening, probes and resources (#99). What a rebuilt
   default must not lose here:
   - liveness and startup run the image's own healthcheck script via
     exec. It queries the server's HTTPS API on SERVERGAMEPORT, so it
     survives a port override, which a tcpSocket default could not.
   - readiness keeps the named "api" port.
   - the resources default keeps limitFactor 2 rather than the repo-wide
     3, which is what holds the memory limit at the published 8Gi.
   - the pod context keeps fsGroupChangePolicy OnRootMismatch, which is
     what avoids a recursive chown of multi-GB game files on every start.

server.storage stays deliberately not null-safe: an erased value yields
an invalid PVC, which is the loud class #99 excludes.

This chart is excluded from the CI install-test, so the local proof is
the only one. Rendering is byte-identical to 4.0.0 with default values
and with the production bundle values, and the rendered manifests were
additionally validated by the cluster's API server via a server-side
dry-run.

satisfactory/templates/_helpers.tpl

@@ -114,3 +114,173 @@ template-chart is the reference implementation.
 1
 {{- end -}}
 {{- end -}}
+
+{{/*
+Merge a user-supplied values sub-tree onto a dict of chart defaults so that a
+null / empty override falls back to the defaults instead of erasing them.
+
+Input: dict "defaults" <dict> "given" <dict|nil> "path" <string, optional
+values path used in error messages>. Output: YAML of the merged dict (consume
+it with fromYaml).
+
+Why this exists (issue #99): Helm merges values maps recursively, but an
+override key written without children — e.g. a leftover
+
+  securityContext:
+
+after deleting its last remaining sub-key — is YAML null. Where the chart
+defines a default, Helm treats that null as a deletion of the default; the
+template then renders "securityContext: null": no readOnlyRootFilesystem, no
+dropped capabilities, no allowPrivilegeEscalation: false. The workload starts
+and reports healthy while being unhardened, so nothing points at the mistake.
+The same shape erases a probe (it disappears) or the resources block (no
+requests, no computed limits). This helper defines the opposite semantics: an
+empty block means "chart defaults apply".
+
+Rules:
+  - a nil "given" is treated as an empty dict (all defaults apply).
+  - a key whose override value is null keeps the default (nulls never delete).
+  - a key present in both as a map is merged recursively, so a partially
+    filled block only overrides the keys it actually sets.
+  - a scalar override for a key the defaults define as a map is rejected with
+    a message naming the values path, instead of failing later with a template
+    field error.
+  - any other set value wins as given, including an explicit false or 0 —
+    Helm's "default" and sprig's "mergeOverwrite" would both swallow those
+    zero values, hence the explicit kindIs "invalid" nil check.
+  - keys only present in the override are passed through unchanged.
+
+NOTE: like the helpers above, this is duplicated into every chart's
+templates/_helpers.tpl with the chart's name as define prefix, because charts
+in this repo deliberately have no dependencies.
+*/}}
+{{- define "satisfactory.defaultedDict" -}}
+{{- $defaults := .defaults | default dict -}}
+{{- $given := .given -}}
+{{- $path := .path | default "value" -}}
+{{- if kindIs "invalid" $given -}}
+{{- $given = dict -}}
+{{- end -}}
+{{- if not (kindIs "map" $given) -}}
+{{- fail (printf "%s must be a mapping or null, got %s (%v)" $path (kindOf $given) $given) -}}
+{{- end -}}
+{{- $out := deepCopy $defaults -}}
+{{- range $key, $value := $given -}}
+{{- if not (kindIs "invalid" $value) -}}
+{{- $default := index $defaults $key -}}
+{{- if and (kindIs "map" $value) (kindIs "map" $default) -}}
+{{- $_ := set $out $key (fromYaml (include "satisfactory.defaultedDict" (dict "defaults" $default "given" $value "path" (printf "%s.%s" $path $key)))) -}}
+{{- else if kindIs "map" $default -}}
+{{- fail (printf "%s.%s must be a mapping or null, got %s (%v)" $path $key (kindOf $value) $value) -}}
+{{- else -}}
+{{- $_ := set $out $key $value -}}
+{{- end -}}
+{{- end -}}
+{{- end -}}
+{{- toYaml $out -}}
+{{- end -}}
+
+{{/*
+Pick one sub-block out of a values block that may itself be null.
+
+Input: dict "block" <dict|nil> "key" <string> "path" <string>.
+Returns YAML of dict "value" <the sub-block, may be nil>, after rejecting a
+non-mapping block with a message that names the values path. Needed because
+".Values.securityContext" can itself be erased.
+*/}}
+{{- define "satisfactory.subBlock" -}}
+{{- $block := .block -}}
+{{- if kindIs "invalid" $block -}}
+{{- $block = dict -}}
+{{- end -}}
+{{- if not (kindIs "map" $block) -}}
+{{- fail (printf "%s must be a mapping or null, got %s (%v)" .path (kindOf $block) $block) -}}
+{{- end -}}
+{{- toYaml (dict "value" (index $block .key)) -}}
+{{- end -}}
+
+{{/*
+The effective security contexts, probes and resources (issue #99).
+
+The defaults below MUST stay in sync with the corresponding blocks in
+values.yaml, which stays the documented, user-facing place for them; this copy
+is only the fallback for the case where an override has erased the block.
+
+Like teamspeak-server, this chart keeps these blocks at the TOP level of
+values.yaml, so the paths in the error messages have no chart-name prefix.
+
+Probe specifics that a rebuilt default must not lose:
+  - liveness and startup run the image's own healthcheck script via exec. It
+    queries the server's HTTPS API on SERVERGAMEPORT, so it keeps working when
+    the port is overridden - which a tcpSocket default could not do.
+  - readiness uses the named "api" port.
+  - the startup budget is deliberately huge (30s x 40 = 20 minutes): the
+    server downloads and updates the game files via Steam on first start.
+*/}}
+{{- define "satisfactory.podSecurityContext" -}}
+{{- $given := (fromYaml (include "satisfactory.subBlock" (dict "block" . "key" "pod" "path" "securityContext"))).value -}}
+{{- $defaults := dict
+      "runAsNonRoot" true
+      "runAsUser" 1000
+      "runAsGroup" 1000
+      "fsGroup" 1000
+      "fsGroupChangePolicy" "OnRootMismatch" -}}
+{{- include "satisfactory.defaultedDict" (dict "defaults" $defaults "given" $given "path" "securityContext.pod") -}}
+{{- end -}}
+
+{{- define "satisfactory.containerSecurityContext" -}}
+{{- $given := (fromYaml (include "satisfactory.subBlock" (dict "block" . "key" "container" "path" "securityContext"))).value -}}
+{{- $defaults := dict
+      "allowPrivilegeEscalation" false
+      "readOnlyRootFilesystem" true
+      "runAsNonRoot" true
+      "capabilities" (dict "drop" (list "ALL") "add" (list)) -}}
+{{- include "satisfactory.defaultedDict" (dict "defaults" $defaults "given" $given "path" "securityContext.container") -}}
+{{- end -}}
+
+{{- define "satisfactory.healthcheckExec" -}}
+{{- dict "command" (list "/bin/sh" "-c" "/home/steam/healthcheck.sh") | toYaml -}}
+{{- end -}}
+
+{{- define "satisfactory.livenessProbe" -}}
+{{- $defaults := dict
+      "exec" (fromYaml (include "satisfactory.healthcheckExec" .))
+      "failureThreshold" 4
+      "successThreshold" 1
+      "periodSeconds" 30
+      "timeoutSeconds" 10 -}}
+{{- include "satisfactory.defaultedDict" (dict "defaults" $defaults "given" . "path" "livenessProbe") -}}
+{{- end -}}
+
+{{- define "satisfactory.readinessProbe" -}}
+{{- $defaults := dict
+      "tcpSocket" (dict "port" "api")
+      "periodSeconds" 10
+      "timeoutSeconds" 5
+      "failureThreshold" 3 -}}
+{{- include "satisfactory.defaultedDict" (dict "defaults" $defaults "given" . "path" "readinessProbe") -}}
+{{- end -}}
+
+{{- define "satisfactory.startupProbe" -}}
+{{- $defaults := dict
+      "exec" (fromYaml (include "satisfactory.healthcheckExec" .))
+      "periodSeconds" 30
+      "timeoutSeconds" 10
+      "failureThreshold" 40 -}}
+{{- include "satisfactory.defaultedDict" (dict "defaults" $defaults "given" . "path" "startupProbe") -}}
+{{- end -}}
+
+{{/*
+The effective resources block, fed into the resources helper above so that an
+erased "resources:" still yields the chart's requests and computed limits.
+The limitFactor default stays 2 here (not the repo-wide 3): the game server
+holds a large world in memory and the factor keeps the memory limit at the
+previously published 8Gi.
+*/}}
+{{- define "satisfactory.effectiveResources" -}}
+{{- $defaults := dict
+      "limitFactor" 2
+      "requests" (dict "memory" "4Gi" "cpu" "1" "ephemeral-storage" "5Gi") -}}
+{{- $merged := fromYaml (include "satisfactory.defaultedDict" (dict "defaults" $defaults "given" . "path" "server.resources")) -}}
+{{- include "satisfactory.resources" $merged -}}
+{{- end -}}

satisfactory/templates/satisfactory.sfs.yaml

@@ -17,7 +17,7 @@ spec:
     spec:
       automountServiceAccountToken: false
       securityContext:
-        {{- toYaml .Values.securityContext.pod | nindent 8 }}
+        {{- include "satisfactory.podSecurityContext" .Values.securityContext | nindent 8 }}
       containers:
         - name: {{ .Release.Name }}-{{ .Chart.Name }}-sfs
           image: "ghcr.io/wolveix/satisfactory-server:{{ .Chart.AppVersion }}"
@@ -73,13 +73,13 @@ spec:
               containerPort: {{ .Values.server.messagingPort }}
               protocol: TCP
           livenessProbe:
-            {{- toYaml .Values.livenessProbe | nindent 12 }}
+            {{- include "satisfactory.livenessProbe" .Values.livenessProbe | nindent 12 }}
           readinessProbe:
-            {{- toYaml .Values.readinessProbe | nindent 12 }}
+            {{- include "satisfactory.readinessProbe" .Values.readinessProbe | nindent 12 }}
           startupProbe:
-            {{- toYaml .Values.startupProbe | nindent 12 }}
+            {{- include "satisfactory.startupProbe" .Values.startupProbe | nindent 12 }}
           resources:
-            {{- include "satisfactory.resources" .Values.server.resources | nindent 12 }}
+            {{- include "satisfactory.effectiveResources" .Values.server.resources | nindent 12 }}
           volumeMounts:
             - name: satisfactory-volume
               mountPath: /config
@@ -104,7 +104,7 @@ spec:
             - name: tmp
               mountPath: /tmp
           securityContext:
-            {{- toYaml .Values.securityContext.container | nindent 12 }}
+            {{- include "satisfactory.containerSecurityContext" .Values.securityContext | nindent 12 }}
       volumes:
         - name: satisfactory-volume
           persistentVolumeClaim: