Managoat

Managoat is the hosted Fountain. Fountain is the open-source engine, and its name is on the CLI, the API, the SDK and this manual. Everything here applies to Managoat unless a page says it is for a self-hosted server.

Deploy on Kubernetes

This guide shows you which manifests to apply, and which to read and not apply.

Use deploy/k8s/

A portable baseline lives in deploy/k8s/. They are plain manifests that you apply with kubectl apply -k. They assume no operators and no CRDs.

You bring a Postgres, an ingress controller, and the fountain-secrets Secret. Its README walks you through the rest. The manifests explain the choices about probes and scale in inline comments.

Track main with Flux

Every merge to main publishes deploy/ as an OCI artifact at ghcr.io/binarybourbon/fountain-manifests, with the image tag built from that commit in place of the release pin. The hosted instance runs from it. A Flux OCIRepository on the tag latest and a Kustomization on the path ./deploy/k8s give you the same, and Flux patches hold your changes.

Run more than one replica

The baseline runs one replica. With more, the pods must form an Erlang cluster, or conversation streams break for the viewer on the other pod. Read Architecture for why.

Add a headless Service that selects the fountain pods. Then set these variables on the container.

- name: POD_IP

  valueFrom:

    fieldRef:

      fieldPath: status.podIP

- name: RELEASE_DISTRIBUTION

  value: name

# The basename must be `fountain_server`, the release name. libcluster

# derives the peer node name from it.

- name: RELEASE_NODE

  value: fountain_server@$(POD_IP)

# The same value on every pod. A missing cookie lets each pod generate its

# own, and the pods never connect.

- name: RELEASE_COOKIE

  valueFrom:

    secretKeyRef:

      name: fountain-secrets

      key: RELEASE_COOKIE

# Pin the distribution port, so a NetworkPolicy can name it.

- name: ERL_AFLAGS

  value: "-kernel inet_dist_listen_min 9100 inet_dist_listen_max 9100"

# The headless Service, as a FQDN.

- name: CLUSTER_DNS_QUERY

  value: fountain-headless.fountain.svc.cluster.local

POD_IP must come before RELEASE_NODE. Kubernetes substitutes only the variables declared earlier. Also open ports 4369 and 9100 between the pods.

Two things to decide

Migrations. Boot migrations are safe with several replicas. A Postgres advisory lock serializes them. To run them as a Job of their own instead, read Run migrations in a Job.

Backups. deploy/k8s/backup-cronjob.yaml sits commented out of the kustomization until you create its secret. Read Back up and restore.

Verify it worked

kubectl rollout status deployment/fountain -n fountain

kubectl exec -n fountain deploy/fountain -- curl -sS localhost:4000/health/ready

If it did not work

Read Pods restart or never go ready. Most symptoms here that look like a Kubernetes fault are the probe layout at work.