From cf725b21737f2a481df1d3a714b056ded97e8b69 Mon Sep 17 00:00:00 2001
From: Victor Marmol <vmarmol@google.com>
Date: Sat, 30 Aug 2014 00:52:25 -0700
Subject: [PATCH] Add a /healthz endpoint to cAdvisor.

Fixes #181
---
 cadvisor.go        |  6 ++++++
 healthz/healthz.go | 16 ++++++++++++++++
 2 files changed, 22 insertions(+)
 create mode 100644 healthz/healthz.go

diff --git a/cadvisor.go b/cadvisor.go
index 7f4ae1eb..cd0b1f60 100644
--- a/cadvisor.go
+++ b/cadvisor.go
@@ -24,6 +24,7 @@ import (
 	"github.com/google/cadvisor/api"
 	"github.com/google/cadvisor/container/docker"
 	"github.com/google/cadvisor/container/raw"
+	"github.com/google/cadvisor/healthz"
 	"github.com/google/cadvisor/info"
 	"github.com/google/cadvisor/manager"
 	"github.com/google/cadvisor/pages"
@@ -60,6 +61,11 @@ func main() {
 		glog.Fatalf("raw registration failed: %v.", err)
 	}
 
+	// Basic health handler.
+	if err := healthz.RegisterHandler(); err != nil {
+		glog.Fatalf("failed to register healthz handler: %s", err)
+	}
+
 	// Handler for static content.
 	http.HandleFunc(static.StaticResource, func(w http.ResponseWriter, r *http.Request) {
 		err := static.HandleRequest(w, r.URL)
diff --git a/healthz/healthz.go b/healthz/healthz.go
new file mode 100644
index 00000000..2c9f0e21
--- /dev/null
+++ b/healthz/healthz.go
@@ -0,0 +1,16 @@
+package healthz
+
+import (
+	"net/http"
+)
+
+func handleHealthz(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte("ok"))
+}
+
+// Register simple HTTP /healthz handler to return "ok".
+func RegisterHandler() error {
+	http.HandleFunc("/healthz", handleHealthz)
+	return nil
+}