Merge pull request #8764 from eparis/sd_notify

API server explicitly notify systemd of successful startup

Godeps/Godeps.json

@@ -98,6 +98,11 @@
 			"ImportPath": "github.com/coreos/go-semver/semver",
 			"Rev": "6fe83ccda8fb9b7549c9ab4ba47f47858bc950aa"
 		},
+		{
+			"ImportPath": "github.com/coreos/go-systemd/daemon",
+			"Comment": "v2-27-g97e243d",
+			"Rev": "97e243d21a8e232e9d8af38ba2366dfcfceebeba"
+		},
 		{
 			"ImportPath": "github.com/coreos/go-systemd/dbus",
 			"Comment": "v2-27-g97e243d",

Godeps/_workspace/src/github.com/coreos/go-systemd/daemon/sdnotify.go

@@ -0,0 +1,31 @@
+// Code forked from Docker project
+package daemon
+
+import (
+	"errors"
+	"net"
+	"os"
+)
+
+var SdNotifyNoSocket = errors.New("No socket")
+
+// SdNotify sends a message to the init daemon. It is common to ignore the error.
+func SdNotify(state string) error {
+	socketAddr := &net.UnixAddr{
+		Name: os.Getenv("NOTIFY_SOCKET"),
+		Net:  "unixgram",
+	}
+
+	if socketAddr.Name == "" {
+		return SdNotifyNoSocket
+	}
+
+	conn, err := net.DialUnix(socketAddr.Net, nil, socketAddr)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	_, err = conn.Write([]byte(state))
+	return err
+}