Fider on GKE Autopilot

Fider is an open-source, self-hosted feedback and feature-voting board — customers post ideas, vote, and comment, and you prioritise by demand. This module deploys Fider on GKE Autopilot on top of the App_GKE foundation, which provisions and manages the shared Google Cloud and Kubernetes infrastructure.

This guide focuses on the cloud services Fider uses and how to explore and operate them from the Google Cloud Console and the command line. For the mechanics that are common to every GKE application — Workload Identity, ingress, autoscaling, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC Service Controls, backups, and the deployment lifecycle — refer to the App_GKE foundation guide rather than repeating them here.

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1. Overview

Fider runs as a single Go web workload. The deployment wires together a focused set of Google Cloud services:

Capability	Google Cloud service	Notes
Compute	GKE Autopilot	Single Go binary, horizontally autoscaled
Database	Cloud SQL for PostgreSQL 15	Required — Fider does not support MySQL or other engines
Object storage	Cloud Storage	A dedicated storage bucket provisioned automatically
File storage	Cloud Filestore (NFS)	Enabled by default for attachment storage
Secrets	Secret Manager	Auto-generated JWT_SECRET; database password
Ingress	Cloud Load Balancing	External LoadBalancer, optional custom domain + managed certificate

Sensible defaults worth knowing up front:

• PostgreSQL 15 is mandatory. The database engine is fixed by the shared application layer (database_type = POSTGRES_15); selecting any other engine breaks startup.
• JWT_SECRET is generated automatically and stored in Secret Manager. It signs all authentication and session tokens (including emailed magic sign-in links) and must never be rotated after first boot — doing so invalidates all active sessions and pending sign-in links.
• Fider is a single Go binary with no background worker. All state lives in PostgreSQL; there is no queue process. A minimum of 1 replica is kept (GKE does not support scale-to-zero).
• No Redis. Fider uses a PostgreSQL-backed queue and cache (empty VALKEY_URL), so enable_redis defaults to false.
• NFS is enabled by default (enable_nfs = true) to provide a Cloud Filestore mount for attachment storage. Because the pod is NFS-backed, App_GKE deploys it with the Recreate strategy rather than RollingUpdate (two pods on the same NFS volume can deadlock on updates).
• The container listens on port 3000. On GKE the PORT env is not auto-injected, so the entrypoint exports PORT = 3000; container_port and the Kubernetes probes must both be 3000 or the pod never becomes Ready even though the app is healthy.
• Schema migrations run on boot. The custom entrypoint runs ./fider migrate before starting the server.
• Email is disabled for the demo. Placeholder SMTP values let the app boot; sign-up / invite links are printed to the pod log until real SMTP is wired via environment_variables.

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2. Google Cloud Services & How to Explore Them

All commands assume you have run gcloud container clusters get-credentials <cluster> --region <region> --project <project> and that PROJECT, REGION, and NAMESPACE are set. The namespace and other identifiers are reported in the deployment Outputs.

A. GKE Autopilot — the Fider workload

Fider pods are scheduled on Autopilot, which bills for the CPU/memory the pods actually request. Horizontal Pod Autoscaling sizes the deployment between the minimum and maximum replica counts.

• Console: Kubernetes Engine → Workloads → select the Fider workload to see pods, revisions, and events. Kubernetes Engine → Services & Ingress shows the external IP.
• CLI:

  kubectl get pods,svc,hpa -n "$NAMESPACE"
  kubectl logs -n "$NAMESPACE" deploy/<service-name> --tail=100
  kubectl describe hpa -n "$NAMESPACE"          # current vs target utilisation

See App_GKE for how Autopilot, scaling, and the workload type (Deployment vs StatefulSet) are managed.

B. Cloud SQL for PostgreSQL 15

Fider stores all application data (posts, votes, comments, users, settings) in a managed Cloud SQL for PostgreSQL 15 instance. Pods reach it privately through the Cloud SQL Auth Proxy sidecar on 127.0.0.1 loopback; no public IP is exposed. On first deploy the db-init Job creates the application role and database; Fider then runs its own migrations on boot.

• Console: SQL → select the instance for connections, backups, flags, and metrics.
• CLI:

  gcloud sql instances list --project "$PROJECT"
  gcloud sql instances describe <instance-name> --project "$PROJECT"
  # Open an interactive shell to inspect schema/data:
  gcloud sql connect <instance-name> --user=<db-user> --database=<db-name> --project "$PROJECT"

The instance name, database name, user, and the Secret Manager secret holding the password are all surfaced in the Outputs. For the connection model, automated backups, and password rotation, see App_GKE.

C. Cloud Storage

A dedicated Cloud Storage bucket (suffix storage) is provisioned automatically. The workload service account is granted access. Additional buckets can be declared via storage_buckets.

• Console: Cloud Storage → Buckets.
• CLI:

  gcloud storage buckets list --project "$PROJECT"
  gcloud storage ls gs://<storage-bucket>/          # bucket name is in the Outputs

See App_GKE for CMEK options and GCS Fuse mounts.

D. Cloud Filestore (NFS)

NFS is enabled by default (enable_nfs = true) to give Fider a Cloud Filestore mount for attachment storage. The shared NFS server VM (managed by Services_GCP) must be RUNNING before the app deploys, and NFS-backed pods use the Recreate update strategy.

• Console: Filestore → Instances.
• CLI:

  gcloud filestore instances list --project "$PROJECT"
  kubectl get pvc,pv -n "$NAMESPACE"

Fider does not use Redis — do not expect a Memorystore or Redis endpoint.

E. Secret Manager

One cryptographic secret is generated automatically and stored in Secret Manager: JWT_SECRET (signs authentication and session tokens). It is delivered into the pod via the Secret Store CSI integration. The database password is managed separately by the foundation.

• Console: Security → Secret Manager.
• CLI:

  gcloud secrets list --project "$PROJECT" --filter="name~fider"
  gcloud secrets versions access latest --secret=<secret-name> --project "$PROJECT"

The database password secret name is in the Outputs. See App_GKE for the Secret Store CSI integration and rotation.

F. Networking & ingress

By default the workload is exposed through an external Cloud Load Balancing IP (service_type = LoadBalancer). A custom domain with a Google-managed certificate can be enabled, and a static IP can be reserved so the address survives redeploys. Set BASE_URL (via environment_variables) to the external URL once the IP is known.

• Console: Network services → Load balancing; VPC network → IP addresses.
• CLI:

  kubectl get ingress,svc -n "$NAMESPACE"
  gcloud compute addresses list --project "$PROJECT"

See App_GKE for custom domains, Cloud CDN, and static IP details.

G. Cloud Logging & Monitoring

Pod stdout/stderr flow to Cloud Logging; GKE and Cloud SQL metrics flow to Cloud Monitoring. Optional uptime checks and alert policies are available. When email is disabled, sign-up / invite links appear in the pod logs.

• Console: Logging → Logs Explorer; Monitoring → Dashboards / Alerting.
• CLI:

  gcloud logging read 'resource.type="k8s_container" AND resource.labels.namespace_name="'"$NAMESPACE"'"' \
    --project "$PROJECT" --limit 50

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3. Fider Application Behaviour

• First-deploy database setup. The db-init Job runs db-init.sh using postgres:15-alpine. It connects through the Cloud SQL Auth Proxy and idempotently creates the fider role and database, grants privileges, reassigns ownership of the public schema to the application role, and signals the proxy sidecar to shut down so the Job pod completes. The job is safe to re-run.
• Schema migrations on start. The custom entrypoint runs ./fider migrate before launching the server (the image's CMD is overridden to ./fider only). Migrations are idempotent, so upgrading the application version applies schema changes on the next start without a separate migration step.
• JWT_SECRET is immutable after first boot. It is generated once and written to Secret Manager. Changing it invalidates all active user sessions and any pending emailed sign-in links. Only rotate during a planned maintenance window.
• First-run setup. There are no default credentials. Browse to the LoadBalancer external IP / URL to create the site and its admin owner:

  kubectl get svc -n "$NAMESPACE" -o wide

• Email is off by default. Placeholder SMTP values let Fider boot with EMAIL_NOEMAIL = true; sign-up and invite links are printed to the pod log. To send real mail, set the Fider SMTP variables via environment_variables and remove EMAIL_NOEMAIL.
• Health path. Startup and liveness probes target /_health — an unauthenticated endpoint returning 200. The container_port and probe port must both be 3000 (the entrypoint exports PORT = 3000; GKE does not auto-inject it).
• NFS-backed updates use Recreate. A rolling update would briefly run two pods against the same NFS volume and shared database; App_GKE therefore sets the strategy to Recreate for NFS-backed apps.
• Inspect job execution:

  kubectl get jobs -n "$NAMESPACE"
  kubectl logs -n "$NAMESPACE" job/<job-name>

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4. Configuration Variables

Variables are grouped exactly as they appear on the deployment platform. Only settings specific to or notable for Fider are listed; every other input is inherited from App_GKE with its standard behaviour and defaults.

Group 3 — Application Identity

Variable	Default	Description
application_name	fider	Base name for resources. Do not change after first deploy.
application_version	latest	Fider image tag (getfider/fider:<tag>), mapped to the FIDER_VERSION build ARG. latest is pinned to stable (no :latest tag exists); pin to a SHA tag in production.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
min_instance_count	1	Minimum replicas; GKE does not support scale-to-zero.
max_instance_count	5	Maximum replicas.
container_port	3000	Fider listens on 3000; probes must match.
container_resources	2 vCPU / 4 GiB	CPU/memory limits and requests for the Fider container.
enable_cloudsql_volume	true	Cloud SQL Auth Proxy sidecar for connections.
enable_image_mirroring	true	Mirror the Fider image into Artifact Registry before deployment.

Group 5 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Extra non-secret settings. Wire real SMTP (EMAIL_SMTP_*, EMAIL_NOREPLY) or the external BASE_URL here. Do not set DATABASE_URL, JWT_SECRET, or PORT.
secret_environment_variables	{}	Map of env var → Secret Manager secret name.

Group 6 — GKE Backend & Cluster

Variable	Default	Description
service_type	LoadBalancer	How the Kubernetes Service is exposed.
workload_type	null	Resolves to Deployment (the module's built-in logic); Fider is stateless (state lives in PostgreSQL / NFS).
session_affinity	ClientIP	Sticky routing (default).
container_protocol	http1	Fider serves standard HTTP/1.1.

Group 7 — StatefulSet

Variable	Default	Description
stateful_pvc_enabled	null	Defaults to the module's built-in logic. Fider stores state in PostgreSQL and NFS, so per-pod PVCs are not required.

Group 13 — Filesystem (NFS)

Variable	Default	Description
enable_nfs	true	Cloud Filestore mount for Fider attachment storage. NFS-backed pods deploy with Recreate.
nfs_mount_path	/opt/fider/storage	Mount path inside the container.

Group 15 — Redis Cache & Queue

Variable	Default	Description
enable_redis	false	Fider is Postgres-backed; leave off unless externalising to Redis.
redis_host / redis_port / redis_auth	"" / 6379 / ""	Only relevant if Redis is enabled.

Group 16 — Database Backend

Variable	Default	Description
database_type	POSTGRES_15	Fixed — Fider requires PostgreSQL 15+.
application_database_name	fider	PostgreSQL database name. Immutable after first deploy.
application_database_user	fider	Application database user. Immutable after first deploy.

All other inputs follow standard App_GKE behaviour.

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5. Outputs

These values are returned on a successful deployment and are the quickest way to locate and explore the running resources.

Output	Description
service_name	Kubernetes Service name.
namespace	Namespace the workload runs in.
service_cluster_ip	In-cluster ClusterIP.
stage_service_cluster_ips	Map of ClusterIPs for stage-specific services.
service_external_ip	External LoadBalancer IP (when a static IP is reserved).
service_url	URL to reach Fider.
database_instance_name	Cloud SQL instance name.
database_name	Application database name.
database_user	Application database user.
database_password_secret	Secret Manager secret holding the DB password.
database_host / database_port	DB endpoint (127.0.0.1 via the Auth Proxy) / port.
storage_buckets	Created Cloud Storage buckets.
network_name / network_exists / regions	VPC network, presence, available regions.
container_image / container_registry	Deployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channels	Monitoring status and channels.
initialization_jobs / db_import_job	Names of the setup and (optional) import jobs.
deployment_id / tenant_id / resource_prefix	Naming identifiers.
project_id / project_number	Project identifiers.
cicd_enabled / cicd_configuration	CI/CD status and details (repo, trigger, registry).
github_repository_url / github_repository_owner / github_repository_name	CI/CD GitHub details.
artifact_registry_repository / cloudbuild_trigger_name / cloudbuild_trigger_id	Registry and build trigger.
kubernetes_ready	Whether the cluster/workload is ready.
vpc_sc_enabled / vpc_sc_perimeter_name / vpc_sc_dry_run_mode	VPC-SC status.
audit_logging_enabled / artifact_registry_cmek_enabled	Audit logging and CMEK status.

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6. Configuration Pitfalls & Sensible Defaults

Risk: Critical (data loss / outage / security) — High (service degraded) — Medium (cost or partial degradation) — Low (minor).

Inherited plan-time validation. This module passes its configuration through the App_GKE foundation engine, which validates values and combinations at plan time — a read replica without its primary, IAP with no authorized identities, a gen1 runtime with NFS/GCS mounts, a database_type that does not match an enabled extension, an out-of-range redis_port/backup_retention_days. Invalid configuration fails the plan with a clear, named error before any resource is created, so most mistakes below are caught up front rather than at apply or runtime.

Setting	Sensible value	Risk	Consequence if wrong
JWT_SECRET (auto-generated)	Never rotate after first boot	Critical	Rotating it invalidates all active sessions and pending emailed sign-in links.
application_database_name / application_database_user	Set once	Critical	Immutable after first deploy; renaming recreates the DB/role and destroys all data.
database_type	POSTGRES_15	Critical	Any non-PostgreSQL engine breaks startup — Fider is Postgres-only.
enable_backup_import	false unless restoring	Critical	Enabling without a valid backup source fails the import job.
container_port	3000	High	GKE does not auto-inject PORT; a mismatched port makes probes hit a dead port and the pod never becomes Ready.
enable_cloudsql_volume	true	High	The Auth Proxy sidecar is required for PostgreSQL connectivity on GKE.
application_version	pin a SHA tag; latest → stable	High	getfider/fider has no :latest tag; the module pins latest to stable, but pin explicitly for reproducible upgrades.
min_instance_count	1	High	GKE requires min ≥ 1; the validation guard rejects invalid values.
enable_nfs	true (default)	Medium	The shared NFS VM must be RUNNING before deploy; NFS-backed pods use Recreate, so a rollout briefly takes the pod down.
quota_memory_requests / _limits	binary units (4Gi, 8192Mi)	Critical	Bare integers are bytes and block all pod scheduling in the namespace.
SMTP (EMAIL_SMTP_*)	Configure for real mail	Medium	Left as placeholders, sign-up / invite links only appear in the logs — no email is sent.
enable_iap	only when public access not needed	High	IAP blocks all unauthenticated requests, including anonymous browsing of the board.

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For the foundation behaviour referenced throughout — IAM and Workload Identity, autoscaling, ingress and certificates, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC-SC, backups, and image mirroring — see App_GKE. Fider-specific application configuration shared with the Cloud Run variant is described in Fider_Common.