mg4/k8s/README.md

Kubernetes manifests — car.k8s.stinnesbeck.com

Plain manifests for the car server, InfluxDB 2 and Grafana. They are only files: nothing here is applied automatically. Apply them yourself.

File	What
namespace.yaml	Namespace mg4
influxdb.yaml	InfluxDB 2.7.12 StatefulSet (10Gi PVC, default storage class), cluster-internal Service, NetworkPolicy admitting only the server and Grafana
server.yaml	Go server Deployment (1 replica, non-root, read-only root filesystem) and Service
grafana.yaml	Grafana 13.2.3 Deployment (1Gi PVC), Service; datasource and dashboards provisioned
grafana/	The provisioned InfluxDB datasource and the MG4 dashboards (Live, Consumption, Charging)
ingress.yaml	Traefik IngressRoutes for car.k8s.stinnesbeck.com and Grafana, TLS from Traefik's default certificate
secrets/secrets.example.yaml	Template for the Secrets; placeholders only, not in kustomization.yaml
secrets/secrets.yaml	Your filled-in copy — gitignored, never committed
kustomization.yaml	Everything except the Secrets; generates the Grafana ConfigMaps

Before the first apply

1. Check ingress.yaml: Grafana's host (placeholder car-grafana.k8s.stinnesbeck.com). Both routes use the traefik-internal class, and both hosts must be covered by Traefik's default certificate.
2. Create the Secrets. cp k8s/secrets/secrets.example.yaml k8s/secrets/secrets.yaml (gitignored), replace every CHANGE-ME there (openssl rand -hex 32): influxdb-auth, mg4-server (ingest token, approval password for pairing, the forge token for app updates) and grafana-admin. Keep the template itself on placeholders only.
3. Registry access. The mg4-server package on git.stinnesbeck.com is public, so no pull secret is needed. If you make it private, add an imagePullSecrets entry to server.yaml.

Apply

kubectl apply -f k8s/namespace.yaml
kubectl apply -f k8s/secrets/secrets.yaml
kubectl apply -k k8s/

Use -k, not -f k8s/: plain -f applies the files without kustomize, so the Grafana ConfigMaps (datasource and dashboards) are never created and Grafana does not start.

Grafana's InfluxDB token

Grafana reads InfluxDB with a token that can only read the mg4 bucket. Nothing to do: an init container in the Grafana pod creates it at every start with the admin token, deletes the one from the previous start, and hands Grafana only the read-only token (in a memory-backed volume). The Grafana process itself never sees the admin token. InfluxDB generates every token but the admin one itself, which is why this cannot be a value in the Secret.

App updates

The server relays the app's releases from the private repository to the car's updater (OTA.md). It reads them with FORGE_TOKEN from the mg4-server Secret: create a token in the forge that can only read the nils/mg4 repository, put it there, apply the Secret and restart the server. Without it, updates are off (the car's updater gets a 404). FORGE_URL and FORGE_REPO are set in server.yaml.

Agent access

agent-access/ creates a service account limited to the mg4 namespace (read-only by default, no Secrets, no exec) and a script that writes a kubeconfig with a time-limited token for it. Applied separately, with kubectl apply -k k8s/agent-access/.

Notes

• InfluxDB's setup mode runs only on an empty volume. Changing admin-token in the Secret later does not change the token inside InfluxDB.
• The server uses the InfluxDB admin token; a token scoped to read/write on the mg4 bucket can replace it later. Grafana has its own read-only token (above).
• The dashboards are read-only in Grafana's UI. Change the JSON in grafana/dashboards/; the ConfigMap name changes with its content, which rolls Grafana.
• The server image is pinned by digest in server.yaml. To upgrade, push a new tag and put its digest there (skopeo inspect docker://git.stinnesbeck.com/nils/mg4-server:<tag>).