Add a custom controller example

examples/custom-controller/server.go

@@ -0,0 +1,82 @@
+package main
+
+import (
+	"log"
+	"net/http"
+	"os/exec"
+	"strings"
+
+	nginxconfig "k8s.io/ingress/controllers/nginx/pkg/config"
+	"k8s.io/ingress/core/pkg/ingress"
+	"k8s.io/ingress/core/pkg/ingress/controller"
+	"k8s.io/ingress/core/pkg/ingress/defaults"
+	"k8s.io/kubernetes/pkg/api"
+)
+
+func main() {
+	dc := newDummyController()
+	ic := controller.NewIngressController(dc)
+	defer func() {
+		log.Printf("Shutting down ingress controller...")
+		ic.Stop()
+	}()
+	ic.Start()
+}
+
+func newDummyController() ingress.Controller {
+	return &DummyController{}
+}
+
+type DummyController struct{}
+
+func (dc DummyController) SetConfig(cfgMap *api.ConfigMap) {
+	log.Printf("Config map %+v", cfgMap)
+}
+
+func (dc DummyController) Reload(data []byte) ([]byte, bool, error) {
+	out, err := exec.Command("echo", string(data)).CombinedOutput()
+	if err != nil {
+		log.Printf("Reloaded new config %s", out)
+	} else {
+		return out, false, err
+	}
+	return out, true, err
+}
+
+func (dc DummyController) Test(file string) *exec.Cmd {
+	return exec.Command("echo", file)
+}
+
+func (dc DummyController) OnUpdate(updatePayload ingress.Configuration) ([]byte, error) {
+	log.Printf("Received OnUpdate notification")
+	for _, b := range updatePayload.Backends {
+		eps := []string{}
+		for _, e := range b.Endpoints {
+			eps = append(eps, e.Address)
+		}
+		log.Printf("%v: %v", b.Name, strings.Join(eps, ", "))
+	}
+	return []byte(`<string containing a configuration file>`), nil
+}
+
+func (dc DummyController) BackendDefaults() defaults.Backend {
+	// Just adopt nginx's default backend config
+	return nginxconfig.NewDefault().Backend
+}
+
+func (n DummyController) Name() string {
+	return "dummy Controller"
+}
+
+func (n DummyController) Check(_ *http.Request) error {
+	return nil
+}
+
+func (dc DummyController) Info() *ingress.BackendInfo {
+	return &ingress.BackendInfo{
+		Name:       "dummy",
+		Release:    "0.0.0",
+		Build:      "git-00000000",
+		Repository: "git://foo.bar.com",
+	}
+}