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K8s Sync Status Headers

The Admin UI Health page reads deployment metadata from HTTP response headers on /api/health/ready to display the running container image, digest, and release information.

How It Works

  1. Backend sets headers via a global interceptor
  2. Admin UI reads headers from health endpoint response
  3. "K8s Sync Status" card displays the values

Environment Variables

Set any of the following in your deployment to expose real values:

Image Information

VariableFallbacks
APP_IMAGECONTAINER_IMAGE, IMAGE
APP_IMAGE_REGISTRY + APP_TAGCombined as registry/tag

Digest Information

VariableFallbacks
APP_IMAGE_DIGESTIMAGE_DIGEST, CI_IMAGE_DIGEST

Release Information

VariableFallbacks
APP_RELEASEGIT_SHA, CI_COMMIT_SHA, CI_COMMIT_TAG, CI_COMMIT_SHORT_SHA
APP_VERSIONVERSION

Response Headers

Headers exposed by the API (if values are available):

HeaderSource
x-app-imageImage name
x-container-imageFull container reference
x-image-digestImage digest (sha256:...)
docker-content-digestAlternative digest header
x-releaseGit SHA or release tag
x-app-versionSemantic version

Admin UI Display

The "K8s Sync Status" card shows:

  • Image: Container image name
  • Digest: Image content hash
  • Release: Git commit or tag
  • Version: Semantic version

If values are not set, the card displays "not exposed".

Kubernetes Deployment Example

apiVersion: apps/v1
kind: Deployment
metadata:
name: access-control-backend
spec:
template:
spec:
containers:
- name: backend
image: registry.digiwedge.com/digiwedge/access-control-backend:v1.2.3
env:
- name: APP_IMAGE
value: "access-control-backend"
- name: APP_VERSION
value: "1.2.3"
- name: APP_RELEASE
valueFrom:
fieldRef:
fieldPath: metadata.labels['app.kubernetes.io/version']

ArgoCD Integration

With ArgoCD Image Updater, the digest is automatically tracked:

metadata:
annotations:
argocd-image-updater.argoproj.io/image-list: backend=registry.digiwedge.com/digiwedge/access-control-backend
argocd-image-updater.argoproj.io/backend.update-strategy: digest