adds the prometheus operator and setups cluster monitoring

pkg/addons/addon_prometheus.go

@@ -0,0 +1,99 @@
+package addons
+
+import (
+	"github.com/xetys/hetzner-kube/pkg/clustermanager"
+	"github.com/xetys/hetzner-kube/pkg/hetzner"
+	"fmt"
+)
+
+// PrometheusAddon provides cluster monitoring using prometheus operator
+type PrometheusAddon struct {
+	masterNode   *clustermanager.Node
+	communicator clustermanager.NodeCommunicator
+	nodes        []clustermanager.Node
+	provider     *hetzner.Provider
+}
+
+func NewPrometheusAddon(provider clustermanager.ClusterProvider, communicator clustermanager.NodeCommunicator) ClusterAddon  {
+	masterNode, err := provider.GetMasterNode()
+	FatalOnError(err)
+	return &PrometheusAddon{
+		masterNode:   masterNode,
+		communicator: communicator,
+		nodes:        provider.GetAllNodes(),
+		provider:     provider.(*hetzner.Provider),
+	}
+}
+
+func init() {
+	addAddon(NewPrometheusAddon)
+}
+
+//Name returns the addons name
+func (addon *PrometheusAddon) Name() string {
+	return "kube-prometheus"
+}
+
+//Requires returns a slice with the name of required addons
+func (addon *PrometheusAddon) Requires() []string {
+	return []string{}
+}
+
+//Description returns the addons description
+func (addon *PrometheusAddon) Description() string {
+	return "CoreOS prometheus operator /w cluster monitoring"
+}
+
+//URL returns the URL of the addons underlying project
+func (addon *PrometheusAddon) URL() string {
+	return "https://github.com/coreos/prometheus-operator"
+}
+
+// Install installs the prometheus operator
+func (addon *PrometheusAddon) Install(args ...string) {
+	// apply cAdvisor and kubelet config
+	kubeletModifyScript := `#!/bin/bash
+
+KUBEADM_SYSTEMD_CONF=/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
+sed -e "/cadvisor-port=0/d" -i "$KUBEADM_SYSTEMD_CONF"
+if ! grep -q "authentication-token-webhook=true" "$KUBEADM_SYSTEMD_CONF"; then
+  sed -e "s/--authorization-mode=Webhook/--authentication-token-webhook=true --authorization-mode=Webhook/" -i "$KUBEADM_SYSTEMD_CONF"
+fi
+systemctl daemon-reload
+systemctl restart kubelet`
+
+	for _, node := range addon.nodes {
+		err := addon.communicator.WriteFile(node, "/tmp/prometheus.sh", kubeletModifyScript, true)
+		FatalOnError(err)
+		_, err = addon.communicator.RunCmd(node, "/tmp/prometheus.sh")
+		FatalOnError(err)
+
+		if node.IsMaster {
+			_, err = addon.communicator.RunCmd(node, `sed -e "s/- --address=127.0.0.1/- --address=0.0.0.0/" -i /etc/kubernetes/manifests/kube-controller-manager.yaml`)
+			FatalOnError(err)
+			_, err = addon.communicator.RunCmd(node, `sed -e "s/- --address=127.0.0.1/- --address=0.0.0.0/" -i /etc/kubernetes/manifests/kube-scheduler.yaml`)
+			FatalOnError(err)
+		}
+	}
+
+	// get the repo
+	addon.run("git clone https://github.com/coreos/prometheus-operator")
+	// get the customized manifests
+	addon.run("cd /root/prometheus-operator/contrib/kube-prometheus/example-dist && git clone https://github.com/xetys/hetzner-kube-prometheus")
+	// install the operator
+	addon.run("cd /root/prometheus-operator/contrib/kube-prometheus && ./hack/cluster-monitoring/deploy example-dist/hetzner-kube-prometheus")
+}
+
+// Uninstall removes the prometheus operator
+func (addon *PrometheusAddon) Uninstall() {
+	addon.run("cd /root/prometheus-operator/contrib/kube-prometheus/ && ./hack/cluster-monitoring/teardown")
+	addon.run("rm -rf prometheus-operator")
+}
+
+func (addon *PrometheusAddon) run(cmd string) {
+	out, err := addon.communicator.RunCmd(*addon.masterNode, cmd)
+	if err != nil {
+		fmt.Printf("Failing command:\n%s\nOutput: %s\n\n", cmd, out)
+		FatalOnError(err)
+	}
+}