From c805e2b371320ceefaf8c9322edd51cb5d964635 Mon Sep 17 00:00:00 2001
From: Brian Waldon <bcwaldon@gmail.com>
Date: Tue, 4 Mar 2014 21:02:20 -0800
Subject: [PATCH] feat(script): Persist transient unit name to disk

---
 cloudinit/systemd.go   | 6 +++---
 cloudinit/workspace.go | 5 +++++
 coreos-cloudinit.go    | 4 +++-
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/cloudinit/systemd.go b/cloudinit/systemd.go
index e7c5f7e..4185e39 100644
--- a/cloudinit/systemd.go
+++ b/cloudinit/systemd.go
@@ -20,7 +20,7 @@ func StartUnit(name string) error {
 	return err
 }
 
-func ExecuteScript(scriptPath string) error {
+func ExecuteScript(scriptPath string) (string, error) {
 	props := []dbus.Property{
 		dbus.PropDescription("Unit generated and executed by coreos-cloudinit on behalf of user"),
 		dbus.PropExecStart([]string{"/bin/bash", scriptPath}, false),
@@ -33,9 +33,9 @@ func ExecuteScript(scriptPath string) error {
 
 	conn, err := dbus.New()
 	if err != nil {
-		return err
+		return "", err
 	}
 
 	_, err = conn.StartTransientUnit(name, "replace", props...)
-	return err
+	return name, err
 }
diff --git a/cloudinit/workspace.go b/cloudinit/workspace.go
index c531439..c63d8c0 100644
--- a/cloudinit/workspace.go
+++ b/cloudinit/workspace.go
@@ -59,3 +59,8 @@ func PersistScriptInWorkspace(script Script, workspace string) (string, error) {
 
 	return f.Name(), nil
 }
+
+func PersistScriptUnitNameInWorkspace(name string, workspace string) error {
+	unitPath := path.Join(workspace, "scripts", "unit-name")
+	return ioutil.WriteFile(unitPath, []byte(name), 644)
+}
diff --git a/coreos-cloudinit.go b/coreos-cloudinit.go
index 9c73d30..a986aef 100644
--- a/coreos-cloudinit.go
+++ b/coreos-cloudinit.go
@@ -75,7 +75,9 @@ func main() {
 		var path string
 		path, err = cloudinit.PersistScriptInWorkspace(t, workspace)
 		if err == nil {
-			err = cloudinit.ExecuteScript(path)
+			var name string
+			name, err = cloudinit.ExecuteScript(path)
+			cloudinit.PersistScriptUnitNameInWorkspace(name, workspace)
 		}
 	}