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

No ingress gate change: this chart already honours ingress.enabled, and
its ingress block keeps the upstream-style host/tls lists that the README
documents as an exception. The schema models that shape as it is instead
of pushing the repo's domain/clusterIssuer pair onto it, and the list
entries stay open because they go verbatim into the Ingress spec.

The domain checkpoint ran over values.yaml and templates and came back
empty: ingress.domain does not exist in this chart at all.

1. values.schema.json (#68): additionalProperties: false on every
   chart-owned object level. Pod-spec passthrough (volumes, volumeMounts,
   nodeSelector, tolerations, affinity, ingress hosts/tls) stays open.

2. Null-safety for hardening, probes and resources (#99).

   This chart's hardening is a documented deviation and the fallbacks
   reproduce it exactly: the pod context is deliberately EMPTY, because
   the official image must start as root (s6-overlay does its setup as
   uid 0 and the image has no non-root user), and capabilities.add keeps
   NET_RAW, without which device discovery (DHCP watcher, ping/arp
   integrations) logs "Operation not permitted".

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

The #82 limitation around the 1Password-backed config Secret is
untouched: Helm never sees the content, so it cannot be hashed, and the
values.yaml note about the manual rollout restart stays as it is.

Rendering with normal values is byte-identical to 5.0.0.

homeassistant/Chart.yaml

@@ -4,7 +4,7 @@ description: A Helm chart to deploy Home Assistant on Kubernetes
 icon: https://www.home-assistant.io/images/home-assistant-logo.svg
 type: application
 
-version: 5.0.0+up2026.8.3
+version: 6.0.0+up2026.8.3
 
 appVersion: "2026.8.3"
 

homeassistant/templates/_helpers.tpl

@@ -114,3 +114,165 @@ 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". 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 "homeassistant.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 "homeassistant.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 "homeassistant.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 several other charts here, this one keeps replicas, resources, probes and
+securityContext at the TOP level of values.yaml, so the paths in the error
+messages have no chart-name prefix.
+
+IMPORTANT - this chart's hardening is a DOCUMENTED DEVIATION and the fallbacks
+reproduce it exactly rather than restoring the repo standard:
+
+  - The pod context is deliberately EMPTY: the official Home Assistant
+    container must start as root (s6-overlay performs its setup as uid 0 and
+    the image supports no non-root user), so runAsNonRoot / runAsUser are not
+    set.
+  - capabilities.add keeps NET_RAW: Home Assistant's device discovery (DHCP
+    watcher, ping/arp integrations) uses raw sockets and logs "Operation not
+    permitted" without it.
+
+The probes address the container port by its name ("http").
+*/}}
+{{- define "homeassistant.podSecurityContext" -}}
+{{- $given := (fromYaml (include "homeassistant.subBlock" (dict "block" . "key" "pod" "path" "securityContext"))).value -}}
+{{- $defaults := dict -}}
+{{- include "homeassistant.defaultedDict" (dict "defaults" $defaults "given" $given "path" "securityContext.pod") -}}
+{{- end -}}
+
+{{- define "homeassistant.containerSecurityContext" -}}
+{{- $given := (fromYaml (include "homeassistant.subBlock" (dict "block" . "key" "container" "path" "securityContext"))).value -}}
+{{- $defaults := dict
+      "allowPrivilegeEscalation" false
+      "readOnlyRootFilesystem" true
+      "capabilities" (dict "drop" (list "ALL") "add" (list "NET_RAW")) -}}
+{{- include "homeassistant.defaultedDict" (dict "defaults" $defaults "given" $given "path" "securityContext.container") -}}
+{{- end -}}
+
+{{- define "homeassistant.livenessProbe" -}}
+{{- $defaults := dict
+      "httpGet" (dict "path" "/" "port" "http")
+      "periodSeconds" 10
+      "timeoutSeconds" 5
+      "failureThreshold" 3 -}}
+{{- include "homeassistant.defaultedDict" (dict "defaults" $defaults "given" . "path" "livenessProbe") -}}
+{{- end -}}
+
+{{- define "homeassistant.readinessProbe" -}}
+{{- $defaults := dict
+      "httpGet" (dict "path" "/" "port" "http")
+      "periodSeconds" 10
+      "timeoutSeconds" 5
+      "failureThreshold" 3 -}}
+{{- include "homeassistant.defaultedDict" (dict "defaults" $defaults "given" . "path" "readinessProbe") -}}
+{{- end -}}
+
+{{- define "homeassistant.startupProbe" -}}
+{{- $defaults := dict
+      "httpGet" (dict "path" "/" "port" "http")
+      "periodSeconds" 10
+      "timeoutSeconds" 5
+      "failureThreshold" 30 -}}
+{{- include "homeassistant.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
+instead of a container without any resource accounting.
+*/}}
+{{- define "homeassistant.effectiveResources" -}}
+{{- $defaults := dict
+      "limitFactor" 3
+      "requests" (dict "cpu" 0.2 "memory" "512Mi" "ephemeralStorage" "128Mi") -}}
+{{- $merged := fromYaml (include "homeassistant.defaultedDict" (dict "defaults" $defaults "given" . "path" "resources")) -}}
+{{- include "homeassistant.resources" $merged -}}
+{{- end -}}

homeassistant/templates/homeassistant.sfs.yaml

@@ -30,13 +30,13 @@ spec:
     spec:
       automountServiceAccountToken: false
       securityContext:
-        {{- toYaml .Values.securityContext.pod | nindent 8 }}
+        {{- include "homeassistant.podSecurityContext" .Values.securityContext | nindent 8 }}
       containers:
         - name: "{{ .Release.Name }}-{{ .Chart.Name }}"
           image: "ghcr.io/home-assistant/home-assistant:{{ .Chart.AppVersion }}"
           imagePullPolicy: IfNotPresent
           securityContext:
-            {{- toYaml .Values.securityContext.container | nindent 12 }}
+            {{- include "homeassistant.containerSecurityContext" .Values.securityContext | nindent 12 }}
           env:
             - name: TZ
               value: "{{ .Values.core.timezone }}"
@@ -65,13 +65,13 @@ spec:
               containerPort: 8123
               protocol: TCP
           livenessProbe:
-            {{- toYaml .Values.livenessProbe | nindent 12 }}
+            {{- include "homeassistant.livenessProbe" .Values.livenessProbe | nindent 12 }}
           readinessProbe:
-            {{- toYaml .Values.readinessProbe | nindent 12 }}
+            {{- include "homeassistant.readinessProbe" .Values.readinessProbe | nindent 12 }}
           startupProbe:
-            {{- toYaml .Values.startupProbe | nindent 12 }}
+            {{- include "homeassistant.startupProbe" .Values.startupProbe | nindent 12 }}
           resources:
-            {{- include "homeassistant.resources" .Values.resources | nindent 12 }}
+            {{- include "homeassistant.effectiveResources" .Values.resources | nindent 12 }}
           volumeMounts:
             - mountPath: /config/configuration.yaml
               subPath: configuration.yaml

homeassistant/values.schema.json

@@ -0,0 +1,224 @@
+{
+  "$schema": "https://json-schema.org/draft-07/schema#",
+  "title": "homeassistant values",
+  "description": "Strict values schema (issue #68). additionalProperties is false on every chart-owned object level, so a key that the chart does not read is rejected at render time instead of being silently ignored. The only objects that stay open are the ones passed verbatim into the Kubernetes pod spec (probes, security contexts, volumes, scheduling, global) - the chart does not interpret their contents, so it cannot judge which keys are meaningful. The hardening, probe and resources blocks additionally accept null, because an erased block falls back to the chart defaults (issue #99). Note that this chart keeps replicas, resources, probes and securityContext at the TOP level, and that its ingress block deliberately follows the upstream host/tls style (documented exception in the README).",
+  "type": "object",
+  "additionalProperties": false,
+  "properties": {
+    "global": {
+      "description": "Helm's conventional cross-chart values. Unused by this chart, kept open so an umbrella install cannot break on it.",
+      "type": "object"
+    },
+    "scaleDown": {
+      "type": "boolean"
+    },
+    "replicas": {
+      "type": "integer",
+      "minimum": 0
+    },
+    "service": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "type": {
+          "type": ["string", "null"]
+        },
+        "port": {
+          "type": ["integer", "null"],
+          "minimum": 1,
+          "maximum": 65535
+        }
+      }
+    },
+    "ingress": {
+      "description": "Documented exception (README): this chart keeps the upstream-style flexible ingress values - host and tls lists instead of the repo's required domain/clusterIssuer pair. The list entries go verbatim into the Ingress spec, so they stay open.",
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "enabled": {
+          "type": "boolean"
+        },
+        "className": {
+          "description": "Set to \"\" to omit ingressClassName from the rendered Ingress.",
+          "type": ["string", "null"]
+        },
+        "annotations": {
+          "type": "object"
+        },
+        "hosts": {
+          "type": ["array", "null"]
+        },
+        "tls": {
+          "type": ["array", "null"]
+        }
+      }
+    },
+    "securityContext": {
+      "$ref": "#/definitions/securityContext"
+    },
+    "resources": {
+      "$ref": "#/definitions/resources"
+    },
+    "livenessProbe": {
+      "$ref": "#/definitions/probe"
+    },
+    "readinessProbe": {
+      "$ref": "#/definitions/probe"
+    },
+    "startupProbe": {
+      "$ref": "#/definitions/probe"
+    },
+    "env": {
+      "$ref": "#/definitions/env"
+    },
+    "volumes": {
+      "description": "Additional volumes, rendered verbatim into the pod spec.",
+      "type": ["array", "null"]
+    },
+    "volumeMounts": {
+      "description": "Additional volumeMounts, rendered verbatim into the container.",
+      "type": ["array", "null"]
+    },
+    "nodeSelector": {
+      "description": "Rendered verbatim into the pod spec.",
+      "type": ["object", "null"]
+    },
+    "tolerations": {
+      "description": "Rendered verbatim into the pod spec.",
+      "type": ["array", "null"]
+    },
+    "affinity": {
+      "description": "Rendered verbatim into the pod spec.",
+      "type": ["object", "null"]
+    },
+    "core": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "timezone": {
+          "type": ["string", "null"]
+        },
+        "storage": {
+          "description": "The config PVC. Not null-safe on purpose: an erased block yields an invalid PVC rather than a silently degraded workload.",
+          "type": "object",
+          "additionalProperties": false,
+          "properties": {
+            "size": {
+              "type": ["string", "null"]
+            },
+            "storageClass": {
+              "type": ["string", "null"]
+            }
+          }
+        }
+      }
+    },
+    "secrets": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "configSecretRef": {
+          "description": "op:// item path holding config, http-config and recorder-config. Changing the PATH restarts the pod via the checksum/secret-ref annotation; changing the item CONTENT does not - see the note in values.yaml (#82).",
+          "type": ["string", "null"]
+        }
+      }
+    }
+  },
+  "definitions": {
+    "resources": {
+      "description": "May be null / empty: the chart then falls back to its default requests and computed limits (issue #99) instead of rendering a container without resource accounting.",
+      "type": ["object", "null"],
+      "additionalProperties": false,
+      "properties": {
+        "limitFactor": {
+          "type": "number",
+          "exclusiveMinimum": 0
+        },
+        "requests": {
+          "$ref": "#/definitions/resourceList"
+        },
+        "limits": {
+          "$ref": "#/definitions/resourceList"
+        }
+      }
+    },
+    "resourceList": {
+      "type": ["object", "null"],
+      "additionalProperties": false,
+      "properties": {
+        "cpu": {
+          "type": ["string", "number", "null"]
+        },
+        "memory": {
+          "type": ["string", "number", "null"]
+        },
+        "ephemeral-storage": {
+          "type": ["string", "number", "null"]
+        },
+        "ephemeralStorage": {
+          "type": ["string", "number", "null"]
+        }
+      }
+    },
+    "env": {
+      "type": "array",
+      "items": {
+        "type": "object",
+        "additionalProperties": false,
+        "required": ["name"],
+        "properties": {
+          "name": {
+            "type": "string"
+          },
+          "value": {
+            "type": "string"
+          },
+          "valueFrom": {
+            "type": "object",
+            "additionalProperties": false,
+            "properties": {
+              "secretKeyRef": {
+                "$ref": "#/definitions/keyRef"
+              },
+              "configMapKeyRef": {
+                "$ref": "#/definitions/keyRef"
+              }
+            }
+          }
+        }
+      }
+    },
+    "keyRef": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["name", "key"],
+      "properties": {
+        "name": {
+          "type": "string"
+        },
+        "key": {
+          "type": "string"
+        }
+      }
+    },
+    "securityContext": {
+      "description": "May be null / empty at any level: the chart then falls back to its hardening defaults (issue #99). Note that this chart's hardening is a documented deviation - the pod context is deliberately empty because the image must start as root (s6-overlay), and capabilities.add keeps NET_RAW for device discovery.",
+      "type": ["object", "null"],
+      "additionalProperties": false,
+      "properties": {
+        "pod": {
+          "description": "Merged onto the chart's pod defaults (empty by design) and rendered as the pod's securityContext; kept open because the chart does not interpret the individual fields.",
+          "type": ["object", "null"]
+        },
+        "container": {
+          "description": "Merged onto the chart's container defaults and rendered as the container's securityContext; kept open because the chart does not interpret the individual fields.",
+          "type": ["object", "null"]
+        }
+      }
+    },
+    "probe": {
+      "description": "Merged onto the chart's probe defaults and rendered as a container probe; kept open because the chart does not interpret the individual fields. May be null / empty, which means the defaults apply (issue #99) rather than the probe disappearing.",
+      "type": ["object", "null"]
+    }
+  }
+}