k3s/scripts/test-run-lazypull

#!/bin/bash

all_services=(
    coredns
    local-path-provisioner
    metrics-server
    traefik
)

export NUM_SERVERS=1
export NUM_AGENTS=1
export WAIT_SERVICES="${all_services[@]}"
export SERVER_ARGS="--node-taint=CriticalAddonsOnly=true:NoExecute"

# ---

cluster-pre-hook() {
  export SERVER_ARGS="${SERVER_ARGS}
    --snapshotter=stargz
  "
  export AGENT_ARGS="${AGENT_ARGS}
    --snapshotter=stargz
  "
}
export -f cluster-pre-hook

# ---

start-test() {
    local REMOTE_SNAPSHOT_LABEL="containerd.io/snapshot/remote"
    local TEST_IMAGE="ghcr.io/stargz-containers/k3s-test-ubuntu:20.04-esgz"
    local TEST_POD_NAME=testpod-$(head /dev/urandom | tr -dc a-z0-9 | head -c 10)
    local TEST_CONTAINER_NAME=testcontainer-$(head /dev/urandom | tr -dc a-z0-9 | head -c 10)

    # Create the target Pod
    cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: ${TEST_POD_NAME}
spec:
  containers:
  - name: ${TEST_CONTAINER_NAME}
    image: ${TEST_IMAGE}
    command: ["sleep"]
    args: ["infinity"]
EOF
    wait-for-pod "${TEST_POD_NAME}"

    # Check if all layers are remote snapshots
    NODE=$(kubectl get pods "${TEST_POD_NAME}" -ojsonpath='{.spec.nodeName}')
    LAYER=$(get-topmost-layer "${NODE}" "${TEST_CONTAINER_NAME}")
    LAYERSNUM=0
    for (( ; ; )) ; do
        LAYER=$(docker exec -i "${NODE}" ctr --namespace="k8s.io" snapshot --snapshotter=stargz info "${LAYER}" | jq -r '.Parent')
        if [ "${LAYER}" == "null" ] ; then
            break
        elif [ ${LAYERSNUM} -gt 100 ] ; then
            echo "testing image contains too many layes > 100"
            return 1
        fi
        ((LAYERSNUM+=1))
        LABEL=$(docker exec -i "${NODE}" ctr --namespace="k8s.io" snapshots --snapshotter=stargz info "${LAYER}" \
                    | jq -r ".Labels.\"${REMOTE_SNAPSHOT_LABEL}\"")
        echo "Checking layer ${LAYER} : ${LABEL}"
        if [ "${LABEL}" == "null" ] ; then
            echo "layer ${LAYER} isn't remote snapshot"
            return 1
        fi
    done

    if [ ${LAYERSNUM} -eq 0 ] ; then
        echo "cannot get layers"
        return 1
    fi

    return 0
}
export -f start-test

wait-for-pod() {
    local POD_NAME="${1}"

    if [ "${POD_NAME}" == "" ] ; then
        return 1
    fi

    IDX=0
    DEADLINE=120
    for (( ; ; )) ; do
        STATUS=$(kubectl get pods "${POD_NAME}" -o 'jsonpath={..status.containerStatuses[0].state.running.startedAt}${..status.containerStatuses[0].state.waiting.reason}')
        echo "Status: ${STATUS}"
        STARTEDAT=$(echo "${STATUS}" | cut -f 1 -d '$')
        if [ "${STARTEDAT}" != "" ] ; then
            echo "Pod created"
            break
        elif [ ${IDX} -gt ${DEADLINE} ] ; then
            echo "Deadline exeeded to wait for pod creation"
            return 1
        fi
        ((IDX+=1))
        sleep 1
    done

    return 0
}
export -f wait-for-pod

get-topmost-layer() {
    local NODE="${1}"
    local CONTAINER="${2}"
    local TARGET_CONTAINER=

    if [ "${NODE}" == "" ] || [ "${CONTAINER}" == "" ] ; then
        return 1
    fi

    for (( RETRY=1; RETRY<=50; RETRY++ )) ; do
        TARGET_CONTAINER=$(docker exec -i "${NODE}" ctr --namespace="k8s.io" c ls -q labels."io.kubernetes.container.name"=="${CONTAINER}" | sed -n 1p)
        if [ "${TARGET_CONTAINER}" != "" ] ; then
            break
        fi
        sleep 3
    done
    if [ "${TARGET_CONTAINER}" == "" ] ; then
        return 1
    fi
    LAYER=$(docker exec -i "${NODE}" ctr --namespace="k8s.io" c info "${TARGET_CONTAINER}" | jq -r '.SnapshotKey')
    echo "${LAYER}"
}
export -f get-topmost-layer

# --- create a basic cluster and check for lazy pulling
LABEL=LAZYPULL run-test