Initial commit.

Adds a basic controller that creates a client and connects to
a Kubernetes cluster from within or external.

Dockerfile

@@ -0,0 +1,5 @@
+FROM quay.io/prometheus/busybox:latest
+
+ADD controller /bin/controller
+
+ENTRYPOINT ["/bin/controller"]

Makefile

@@ -0,0 +1,2 @@
+build:
+	go build github.com/coreos/kube-prometheus-controller/cmd/controller

cmd/controller/main.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"github.com/coreos/kube-prometheus-controller/pkg/controller"
+)
+
+var cfg controller.Config
+
+func init() {
+	flagset := flag.NewFlagSet(os.Args[0], flag.ExitOnError)
+
+	flagset.StringVar(&cfg.Host, "apiserver", "", "API Server addr, e.g. ' - NOT RECOMMENDED FOR PRODUCTION - http://127.0.0.1:8080'. Omit parameter to run in on-cluster mode and utilize the service account token.")
+	flagset.StringVar(&cfg.TLSConfig.CertFile, "cert-file", "", " - NOT RECOMMENDED FOR PRODUCTION - Path to public TLS certificate file.")
+	flagset.StringVar(&cfg.TLSConfig.KeyFile, "key-file", "", "- NOT RECOMMENDED FOR PRODUCTION - Path to private TLS certificate file.")
+	flagset.StringVar(&cfg.TLSConfig.CAFile, "ca-file", "", "- NOT RECOMMENDED FOR PRODUCTION - Path to TLS CA file.")
+	flagset.BoolVar(&cfg.TLSInsecure, "tls-insecure", false, "- NOT RECOMMENDED FOR PRODUCTION - Don't verify API server's CA certificate.")
+
+	flagset.Parse(os.Args[1:])
+}
+
+func main() {
+
+	c, err := controller.New(cfg)
+	if err != nil {
+		fmt.Fprint(os.Stderr, err)
+		os.Exit(1)
+	}
+	if err := c.Run(); err != nil {
+		fmt.Fprint(os.Stderr, err)
+		os.Exit(1)
+	}
+}

example/prometheus-controller.yaml

@@ -0,0 +1,10 @@
+apiVersion: v2
+kind: Pod
+metadata:
+  name: prometheus-ctrl
+  labels:
+    name: prometheus-ctrl
+spec:
+  containers:
+  - name: prometheus-ctrl
+    image: quay.io/fabxc/prometheus-ctrl:latest

hack/controller-external.sh

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+if [[ -z "$1" ]]; then
+	echo "missing cluster name"
+	exit 1
+fi
+
+apiserver=$(kubectl config view -o jsonpath="{.clusters[?(@.name == \"$1\")].cluster.server}")
+cafile=$(kubectl config view -o jsonpath="{.clusters[?(@.name == \"$1\")].cluster.certificate-authority}")
+certfile=$(kubectl config view -o jsonpath="{.users[?(@.name == \"$1\")].user.client-certificate}")
+keyfile=$(kubectl config view -o jsonpath="{.users[?(@.name == \"$1\")].user.client-key}")
+
+./controller --apiserver=$apiserver --ca-file=$cafile --cert-file=$certfile --key-file=$keyfile

pkg/controller/controller.go

@@ -0,0 +1,84 @@
+package controller
+
+import (
+	"fmt"
+	"net/url"
+	"os"
+
+	"github.com/go-kit/kit/log"
+	"k8s.io/client-go/1.4/kubernetes"
+	"k8s.io/client-go/1.4/rest"
+)
+
+const (
+	tprMonitor    = "monitor.prometheus.coreos.com"
+	tprPrometheus = "prometheus.prometheus.coreos.com"
+)
+
+// Controller manages lify cycle of Prometheus deployments and
+// monitoring configurations.
+type Controller struct {
+	kclient *kubernetes.Clientset
+	logger  log.Logger
+}
+
+type Config struct {
+	Host        string
+	TLSInsecure bool
+	TLSConfig   rest.TLSClientConfig
+}
+
+func newClient(host string, tlsInsecure bool, tlsConfig *rest.TLSClientConfig) (*kubernetes.Clientset, error) {
+	var cfg *rest.Config
+	var err error
+
+	if len(host) == 0 {
+		if cfg, err = rest.InClusterConfig(); err != nil {
+			return nil, err
+		}
+	} else {
+		cfg = &rest.Config{
+			Host: host,
+		}
+		hostURL, err := url.Parse(host)
+		if err != nil {
+			return nil, fmt.Errorf("error parsing host url %s : %v", host, err)
+		}
+		if hostURL.Scheme == "https" {
+			cfg.TLSClientConfig = *tlsConfig
+			cfg.Insecure = tlsInsecure
+		}
+	}
+	cfg.QPS = 100
+	cfg.Burst = 100
+
+	c, err := kubernetes.NewForConfig(cfg)
+	if err != nil {
+		return nil, err
+	}
+	return c, nil
+}
+
+// New creates a new controller.
+func New(c Config) (*Controller, error) {
+	client, err := newClient(c.Host, c.TLSInsecure, &c.TLSConfig)
+	if err != nil {
+		return nil, err
+	}
+	return &Controller{
+		kclient: client,
+		logger:  log.NewLogfmtLogger(os.Stdout),
+	}, nil
+}
+
+// Run the controller.
+func (c *Controller) Run() error {
+	v, err := c.kclient.Discovery().ServerVersion()
+	if err != nil {
+		return fmt.Errorf("communicating with server failed: %s", err)
+	}
+	c.logger.Log("msg", "connection established", "version", v)
+
+	select {}
+	panic("unreachable")
+}