# This sample's own SandboxTemplate and SandboxWarmPool, in the sample's own
# namespace. Nothing here touches another warm pool on the cluster.
#
# spec.replicas on the pool is a FLOOR that setup applies once. From the moment
# the ScaledObject exists, the Horizontal Pod Autoscaler KEDA creates owns that
# field and writes it from observed SandboxClaim demand, so do not read the
# number below as the size of the pool at run time. The SandboxWarmPool CRD
# defines a /scale subresource whose specReplicasPath is .spec.replicas, which is
# what lets an HPA drive it:
#   kubectl get --raw \
#     /apis/extensions.agents.x-k8s.io/v1beta1/namespaces/<NAMESPACE>/sandboxwarmpools/warm-pool/scale
#
# __NAMESPACE__ is filled in at apply time by the scripts from the NAMESPACE
# variable, so an overridden name reaches this object too. Never apply this file
# with the placeholder in place.
apiVersion: extensions.agents.x-k8s.io/v1beta1
kind: SandboxTemplate
metadata:
  name: warm-pool-agent
  namespace: __NAMESPACE__
  labels:
    app.kubernetes.io/part-of: warm-pool-autoscaling-keda
spec:
  podTemplate:
    metadata:
      labels:
        app.kubernetes.io/part-of: warm-pool-autoscaling-keda
      annotations:
        # No network besides loopback: no route out, no DNS, no instance
        # metadata and no Pod Identity credentials. There is no egress to
        # restrict, so this sample ships no network policy. kubectl exec, cp and
        # logs keep working, because they use the guest's internal control
        # channel, which is how the page reads the claimed pod.
        sandbox.amazonaws.com/network-isolated: "true"
        # Pin the node while a warm pod sits Ready and idle in the pool. Nothing
        # would reschedule a pre-booted warm pod if voluntary disruption
        # (consolidation, drift, expiry) removed the node under it. The pool
        # would notice and boot a replacement, but the reader would see the warm
        # count dip for reasons that have nothing to do with KEDA. The pods go
        # away on scale-down, so this does not hold a node open after the pool
        # shrinks.
        karpenter.sh/do-not-disrupt: "true"
    spec:
      # The one line that puts the pod in a Nitro sandbox. No node selector,
      # toleration or sidecar: the RuntimeClass carries the scheduling
      # constraints, and EKS Auto Mode brings up a sandbox-capable node.
      runtimeClassName: isolated-sandbox
      # No API credential inside the sandbox. A pod built from a SandboxTemplate
      # has this defaulted to false already, so this is saying out loud what the
      # pod relies on rather than changing it: a warm pod runs untrusted code and
      # has no reason to hold a token for the cluster it runs on.
      automountServiceAccountToken: false
      containers:
        - name: agent
          image: public.ecr.aws/docker/library/busybox:1.36
          imagePullPolicy: IfNotPresent
          command: ["sleep", "infinity"]
          # No CPU or memory requests or limits. This sample is about how MANY
          # warm pods the pool holds, not how big each one is, so it leaves
          # sizing to the reader and the guest gets a small default size. A real
          # workload sets the requests it needs: the guest is sized from them.
---
apiVersion: extensions.agents.x-k8s.io/v1beta1
kind: SandboxWarmPool
metadata:
  name: warm-pool
  namespace: __NAMESPACE__
  labels:
    app.kubernetes.io/part-of: warm-pool-autoscaling-keda
spec:
  # The floor, applied once. The ScaledObject's minReplicaCount holds it here at
  # rest and the HPA raises it under demand, up to maxReplicaCount. See the
  # comment at the top of this file.
  replicas: 1
  sandboxTemplateRef:
    name: warm-pool-agent