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Spoolman on GKE Autopilot — Lab Guide

📖 Configuration Guide

Overview​

Estimated time: 30–45 minutes

Spoolman is an open-source inventory and usage tracker for 3D-printing filament spools. This lab takes you through the full operational lifecycle of the Spoolman on GKE Autopilot module on Google Cloud: deploy it, access and verify it, run it day-to-day, observe it, diagnose common problems, and tear it down.

The lab focuses on operating the GKE module and the Google Cloud platform, not on Spoolman product features. For the complete list of provisioned services and every configuration input (organised by group), see the Configuration Guide — this lab deliberately does not duplicate that detail so it stays accurate over time.

Objectives​

By the end of this lab you will be able to:

  • Deploy the module from the RAD platform and locate the resources it provisions.
  • Connect to the GKE cluster and access the running workload.
  • Perform day-2 operations — inspect, scale, update, and manage secrets.
  • Observe the workload with Cloud Logging and Cloud Monitoring.
  • Diagnose and resolve the most common deployment and runtime issues.
  • Tear the deployment down cleanly.

Prerequisites​

  • Services_GCP deployed in the target project (provides the VPC, GKE Autopilot cluster, Cloud SQL, Artifact Registry, and shared service accounts this module depends on).
  • A Google Cloud project with billing enabled.
  • gcloud CLI and kubectl installed; gcloud auth login and gcloud auth application-default login completed.
  • Project Owner (or equivalent) IAM on the project.
  • RAD platform access with permission to deploy modules into the project.

Set these shell variables once; every task below reuses them:

export PROJECT="<your-gcp-project-id>"
export REGION="us-central1"           # the region you deploy into

Task 1 — Deploy the module [Automated]​

  1. Click Deploy in the RAD platform, open Spoolman (GKE), set project_id, and review the inputs. Configure only what you need — the Configuration Guide documents every input by group, with defaults. Review the estimated cost (if credits are enabled) and click Deploy, which opens the deployment status page with real-time logs.

  2. The platform deploys the workload into the GKE Autopilot cluster and provisions a Cloud SQL (PostgreSQL 15) database with its Secret Manager password secret, pulling the prebuilt ghcr.io/donkie/spoolman image directly — there is no Cloud Build step and no database-initialization job to wait for (Spoolman migrates itself on boot). First deploys take roughly 15–25 minutes (Cloud SQL creation dominates).

  3. Connect to the cluster and discover the namespace with name-agnostic filters:

    CLUSTER=$(gcloud container clusters list --project="$PROJECT" --format="value(name)" --limit=1)
    gcloud container clusters get-credentials "$CLUSTER" --region="$REGION" --project="$PROJECT"

    NS=$(kubectl get ns -o name | grep spoolman | head -1 | cut -d/ -f2)
    echo "Cluster: $CLUSTER   Namespace: $NS"
    kubectl get all -n "$NS"

Task 2 — Access & verify [Manual]​

  1. Confirm the workload is running and find its external address:

    kubectl get pods,svc -n "$NS"
    EXTERNAL_IP=$(kubectl get svc -n "$NS" \
      -o jsonpath='{.items[?(@.spec.type=="LoadBalancer")].status.loadBalancer.ingress[0].ip}')
    echo "External IP: $EXTERNAL_IP"

  2. Confirm the service is healthy:

    curl -s "http://${EXTERNAL_IP}/api/health"   # expect a 200/OK JSON status

  3. Open http://${EXTERNAL_IP} in a browser. Spoolman has no login gate — the UI loads directly into the spool inventory dashboard with no admin account to create. If you need to restrict access, apply IAP or a Cloud Armor allowlist now, before sharing the IP with anyone else.

Task 3 — Operate & keep it running (Day-2) [Manual]​

  1. Inspect the workload — deployment and pods:

    kubectl get deploy,pods -n "$NS"
    kubectl describe deploy -n "$NS"

  2. Scale by changing the min/max instance inputs and clicking Update on the deployment details page — the module owns the workload spec, so scaling is a configuration change, not a manual kubectl scale (a manual edit would be reverted on the next apply). Spoolman has no background work, so scale-to-zero (min_instance_count = 0) is safe at any time.

  3. Update the application version by changing the version input in the RAD platform and applying it via Update; Kubernetes pulls the new tag directly from ghcr.io/donkie/spoolman and performs a rolling update — no rebuild is needed since this is a genuinely prebuilt image.

  4. Manage secrets:

    kubectl get secrets -n "$NS"
    gcloud secrets list --project="$PROJECT" --filter="name~spoolman"

  5. Open a database session for inspection or maintenance:

    INSTANCE=$(gcloud sql instances list --project="$PROJECT" --format="value(name)" --limit=1)
    gcloud sql connect "$INSTANCE" --user=spoolman --project="$PROJECT"

Task 4 — Observe: Logging & Monitoring [Manual]​

  1. Logs — from kubectl or the Logs Explorer:

    kubectl logs -n "$NS" deploy/"$(kubectl get deploy -n "$NS" -o jsonpath='{.items[0].metadata.name}')" --tail=50

    Logs Explorer filter: resource.type="k8s_container" AND resource.labels.namespace_name="<namespace>".

  2. Monitoring — open the GKE / Kubernetes dashboards and review pod CPU and memory utilisation and restart counts. The module can provision an uptime check (when enabled); review Monitoring → Uptime checks.

Task 5 — Troubleshoot & debug [Manual]​

Durable techniques for the failure modes you are most likely to hit. These are platform-level diagnostics and do not change with Spoolman releases.

  • Pod not Ready / CrashLoopBackOff: inspect events and logs. The startup and liveness probes both target /api/health with a short initial delay — Spoolman boots fast since there's no separate schema-migration job to wait on. 
    kubectl describe pod -n "$NS" <pod>          # Events section shows scheduling/probe/mount errors
    kubectl logs -n "$NS" <pod> --previous       # logs from the crashed container
  • Database connection errors: confirm the Cloud SQL instance is RUNNABLE and the DB password secret materialised into the namespace. Since there is no init job, this class of failure surfaces directly in the pod's own boot logs.
  • App runs but shows an empty inventory using SQLite instead of Postgres: check whether SPOOLMAN_DB_TYPE=postgres was accidentally overridden or unset in environment_variables: 
    kubectl exec -n "$NS" deploy/<service-name> -- env | grep -i spoolman_db
  • Pending pod / no external IP: check kubectl describe pod events for resource or quota issues, and confirm the LoadBalancer Service has an assigned IP.
  • Image pull errors: confirm the image exists (or mirrors correctly) in Artifact Registry and the node service account can pull it.

See the Configuration Guide's Configuration Pitfalls section for setting-specific gotchas (including the lack of built-in authentication).

Task 6 — Tear down [Automated]​

On the Deployments page, open the deployment and click the Trash icon (Delete). Delete runs terraform destroy and is irreversible (the deployment record is retained for history). If a deployment is stuck and the RAD platform can no longer manage it (for example after manual changes that conflict with the Terraform state), use Purge instead — it removes the deployment from RAD's records without destroying the cloud resources (it makes RAD forget the project). This removes everything the module created — the Kubernetes workload and namespace, Cloud SQL database, and Secret Manager secrets. Resources owned by Services_GCP (the VPC, GKE cluster, shared Cloud SQL, registry) are managed separately and are not removed here.

Summary​

TaskTypeOutcome
1 — DeployAutomatedModule deploys the GKE workload and Cloud SQL (PostgreSQL 15) with its password secret; no build, no init job
2 — Access & verifyManualConnect to the cluster; health check passes; UI loads directly with no login gate
3 — OperateManualInspect workload, scale, update version, manage secrets, DB access
4 — ObserveManualQuery Cloud Logging; review Cloud Monitoring metrics and uptime check
5 — TroubleshootManualDiagnose pod, database, DB-engine-fallback, and image-pull issues
6 — Tear downAutomatedDelete (Trash) removes all module resources

By · Google Cloud certified: ACE · PCA · PCD · PDE · PSE · CDL

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