feat(dispatch-helm): leave components mapped to null out of the chart update

.github/workflows/dispatch-helm.yml

@@ -86,7 +86,7 @@ on:
         type: boolean
         default: true
       values_key_mappings:
-        description: 'JSON mapping of component names to values.yaml keys. If not mapped, uses component name as fallback.'
+        description: 'JSON mapping of component names to values.yaml keys. If not mapped, uses component name as fallback. Map a component to null to leave it out of the chart update.'
         type: string
         default: ''
       legacy_patch_detection:
@@ -350,6 +350,16 @@ jobs:
           # Process each component
           for row in $(echo "$COMPONENTS_JSON" | jq -c '.[]'); do
             COMP_NAME=$(echo "$row" | jq -r '.name')
+
+            # A component mapped to null in values_key_mappings has no place in
+            # the chart (a test mock image, a sidecar the chart does not deploy):
+            # leave it out of the payload. Unmapped components still fall back to
+            # their own name as the values key, which is a root-level key.
+            if [ -n "$VALUES_KEY_MAPPINGS" ] && \
+               echo "$VALUES_KEY_MAPPINGS" | jq -e --arg name "$COMP_NAME" 'type == "object" and has($name) and .[$name] == null' >/dev/null 2>&1; then
+              echo "Skipping ${COMP_NAME}: mapped to null in values_key_mappings"
+              continue
+            fi
             COMP_PATH=$(echo "$row" | jq -r '.path // empty')
             COMP_VERSION=$(echo "$row" | jq -r '.version // empty')
 

docs/dispatch-helm.md

@@ -25,7 +25,7 @@ It also classifies the release: when the tag being dispatched was cut from a mai
 | `components_base_path` | Base path for components in the source repository | no | `components` |
 | `env_file` | Env example file relative to the component path | no | `.env.example` |
 | `detect_env_changes` | Detect environment variables added since the previous release | no | `true` |
-| `values_key_mappings` | JSON mapping of component names to `values.yaml` keys | no | `''` |
+| `values_key_mappings` | JSON mapping of component names to `values.yaml` keys. A key may be nested (`app.migrations` writes `app.migrations.image.tag`). Map a component to `null` to leave it out of the chart update (e.g. a test mock image the chart does not deploy); an unmapped component falls back to its own name as a root-level key | no | `''` |
 | `legacy_patch_detection` | Flag releases cut from maintenance branches as legacy patches | no | `true` |
 | `legacy_branch_patterns` | Glob patterns (newline or comma separated) of maintenance branches | no | `maintenance/*` |
 | `runner_type` | GitHub runner type | no | `blacksmith-4vcpu-ubuntu-2404` |

docs/go-release.md

@@ -58,7 +58,7 @@ A third layout needs `release_single_app: true`: **one semantic-release tag for
 | `helm_chart` | Helm chart name to update (required when `enable_helm_dispatch`) | string | `''` |
 | `helm_detect_env_changes` | Detect new environment variables for Helm during dispatch | boolean | `true` |
 | `helm_env_file` | Example env file `helm_detect_env_changes` reads, relative to each component path. Set it when the repository keeps its example env elsewhere (e.g. `config/.env.example`) — otherwise detection finds nothing. Per-group override: `helm_env_file` | string | `.env.example` |
-| `helm_values_key_mappings` | JSON mapping of component names to values.yaml keys | string | `''` |
+| `helm_values_key_mappings` | JSON mapping of component names to values.yaml keys (nested keys allowed; `null` leaves a component out of the chart update) | string | `''` |
 | `extra_builds` | JSON array of additional build groups, each forwarded to `build.yml` with its own config; all feed the single gitops-update (see [Multiple build groups](#multiple-build-groups)) | string | `''` |
 | `dockerfile_name` | Dockerfile name for the primary build and every `extra_builds` group (per-group override via the group's own `dockerfile_name`); forwarded to `build.yml`, which resolves the path as `{working_dir}/{dockerfile_name}` | string | `'Dockerfile'` |
 | `enable_goreleaser` | Publish binaries with GoReleaser from the repository `.goreleaser.yml`, instead of (or in addition to) container images (see [GoReleaser binary lane](#goreleaser-binary-lane)) | boolean | `false` |