CAPZ-demo: add automation

This change adds automation to prepare and to run the CAPZ demo.
Automation is WIP (see TODOs in capz-demo.env).

What works:

source capz-demo.env
get_prerequisites
setup_kind_cluster
cleanup

What fails:

generate_capz_yaml - some undefined variables in flatcar template yaml
deploy_capz_cluster - no cluster.yaml from previous step

Signed-off-by: Thilo Fromm <[email protected]>

CAPZ-sysext/azure.env.template

@@ -0,0 +1,17 @@
+# Template for Azure CAPZ settings
+
+export AZURE_SUBSCRIPTION_ID="TODO add subscription ID"
+export AZURE_TENANT_ID="TODO add tenant ID"
+export AZURE_CLIENT_ID="TODO add app ID"
+export AZURE_CLIENT_SECRET="TODO add client secret"
+
+#
+# These usually do not need to be touched
+#
+
+export AZURE_CLIENT_ID_USER_ASSIGNED_IDENTITY="${AZURE_CLIENT_ID}" # for compatibility with CAPZ v1.16 templates
+
+# AZURE_RESOURCE_GROUP is set in capz-demo.env
+export AZURE_CLUSTER_IDENTITY_SECRET_NAME="${AZURE_RESOURCE_GROUP}-cluster-identity-secret"
+export CLUSTER_IDENTITY_NAME="${AZURE_RESOURCE_GROUP}-cluster-identity"
+export AZURE_CLUSTER_IDENTITY_SECRET_NAMESPACE="default"

CAPZ-sysext/capz-demo.env

@@ -0,0 +1,168 @@
+#!/bin/bash
+
+AZURE_RESOURCE_GROUP="flatcar-capi-demo-azure"
+export AZURE_RESOURCE_GROUP
+
+WORKER_CONTROLPLANE_NODES=1
+WORKER_NODES=2
+
+p() {
+    echo
+    echo "#####################################"
+    echo "${@}"
+    echo "-------------------------------------"
+}
+# --
+
+check_command() {
+    local cmd="$1"
+
+    if ! command -v "$cmd" &> /dev/null ; then
+        echo "'$cmd' could not be found. Please install your distro's '$cmd'."
+        return 1
+    fi
+    echo "  - '$cmd'"
+}
+# --
+
+check_file() {
+    local f="$1"
+
+    if [ ! -f "./$f" ] ; then
+        echo "prerequisite '$f' could not be found."
+        return 1
+    fi
+
+    echo "  - '$f'"
+}
+# --
+
+get_prerequisites() {
+    p "Prerequisites: Checking for required host commands."
+    check_command "kubectl" || return
+    check_command "yq" || return
+    check_command "wget" || return
+
+    p "Prerequisites: Checking for prerequisite files."
+    check_file "azure.env" || return
+
+    if [ ! -f ./clusterctl ] ; then
+        p "Prerequisites: fetching clusterctl"
+        wget https://github.com/kubernetes-sigs/cluster-api/releases/latest/download/clusterctl-linux-amd64
+        mv clusterctl-linux-amd64 clusterctl
+        chmod 755 clusterctl
+    fi
+
+    if [ ! -f ./kind ] ; then
+        p "Prerequisites: fetching kind"
+        wget https://github.com/kubernetes-sigs/kind/releases/latest/download/kind-linux-amd64
+        mv kind-linux-amd64 kind
+        chmod 755 kind
+    fi
+}
+# --
+
+setup_kind_cluster() {
+    p "Bootsstrapping cluster"
+    ./kind create cluster --kubeconfig=./kind-mgmt.kubeconfig
+    export EXP_KUBEADM_BOOTSTRAP_FORMAT_IGNITION=true
+}
+# --
+
+kc_mgmt() {
+    kubectl --kubeconfig=./kind-mgmt.kubeconfig "${@}"
+
+}
+# --
+
+kc_worker() {
+    kubectl --kubeconfig=./${AZURE_RESOURCE_GROUP}.kubeconfig "${@}"
+}
+# --
+
+generate_capz_yaml() {
+    source ./azure.env
+
+    p "Initialising ClusterAPI Azure provider."
+    ./clusterctl init --infrastructure azure --kubeconfig=./kind-mgmt.kubeconfig
+
+    # FIXME: add
+    #    --infrastructure azure \
+    #    --flavor flatcar-sysext \
+    #        and remove
+    #    --from cluster-template-flatcar-sysext.yaml \
+    #        when https://github.com/kubernetes-sigs/cluster-api-provider-azure/pull/4575 is merged.
+
+    # TODO: define AZURE_CONTROL_PLANE_MACHINE_TYPE, AZURE_LOCATION, AZURE_NODE_MACHINE_TYPE, FLATCAR_VERSION
+    #       missing from cluster-template-flatcar-sysext.yaml
+
+    p "Generating ${AZURE_RESOURCE_GROUP}.yaml."
+    ./clusterctl generate cluster ${AZURE_RESOURCE_GROUP} \
+        --from cluster-template-flatcar-sysext.yaml \
+        --kubeconfig=./kind-mgmt.kubeconfig \
+        --kubernetes-version v1.30.3 \
+        --control-plane-machine-count=${WORKER_CONTROLPLANE_NODES} \
+        --worker-machine-count=${WORKER_NODES} \
+        > ${AZURE_RESOURCE_GROUP}.yaml
+
+    yq -i "with(. | select(.kind == \"AzureClusterIdentity\"); .spec.type |= \"ServicePrincipal\" | .spec.clientSecret.name |= \"${AZURE_CLUSTER_IDENTITY_SECRET_NAME}\" | .spec.clientSecret.namespace |= \"${AZURE_CLUSTER_IDENTITY_SECRET_NAMESPACE}\")" "${AZURE_RESOURCE_GROUP}.yaml"
+}
+# --
+
+deploy_capz_cluster() {
+
+    p "Creating workload cluster"
+    kc_mgmt apply -f ./${AZURE_RESOURCE_GROUP}.yaml
+
+    p "Waiting for cluster to be provisioned."
+    while ! kc_mgmt get cluster | grep "${AZURE_RESOURCE_GROUP}" | grep Provisioned ; do
+        sleep 1
+    done
+
+    # Hack alert: sometimes ended up with an empty kubeconfig from the command below, so
+    #   we add a defensive sleep.
+    sleep 2
+
+    ./clusterctl get kubeconfig ${AZURE_RESOURCE_GROUP} \
+            --kubeconfig=./kind-mgmt.kubeconfig \
+            --namespace default \
+            > ./${AZURE_RESOURCE_GROUP}.kubeconfig
+
+    p "Waiting for all nodes to come up."
+    local count=0
+    local target_count=$((WORKER_CONTROLPLANE_NODES + WORKER_NODES))
+    while [ "$count" -lt "$target_count" ] ; do
+        count="$(kc_worker --request-timeout=1s get nodes \
+                 | grep "${AZURE_RESOURCE_GROUP}" \
+                 | wc -l)"
+        echo "$count of $target_count nodes are up."
+    done
+
+    p "Cluster is deployed and can now be used ('kc_worker' kubectl wrapper)."
+}
+# --
+
+cleanup() {
+    kc_mgmt delete cluster ${AZURE_RESOURCE_GROUP}
+    ./kind delete cluster --kubeconfig=./kind-mgmt.kubeconfig
+}
+# --
+
+help() {
+    cat <<EOF
+Demo functions:
+
+ - get_prerequisites:   Check and download a number of prerequisited.
+ - setup_kind_cluster:  Create a local Kind (Kubernetes-in-docker) cluster we'll use as management cluster.
+ - generate_capz_yaml:  Generate Azure worker cluster configuration.
+ - deploy_capz_cluster: Apply worker cluster config to management cluster. This will create the worker cluster.
+
+You can use kubectl wrappers:
+ - kc_worker: interact with the worker cluster
+ - kc_mgmt: interact with the management cluster.
+
+ - 'cleanup' will tear down the worker cluster and remove the local management cluster.
+EOF
+}
+
+help