✨ KAI support. (#64)

Add support for fetch the `head` commit.

---------

Signed-off-by: Jeff Ortel <jortel@redhat.com>

repository/factory.go

@@ -57,6 +57,7 @@ type SCM interface {
 	Fetch() (err error)
 	Branch(name string) (err error)
 	Commit(files []string, msg string) (err error)
+	Head() (commit string, err error)
 }
 
 // Remote repository.

repository/git.go

@@ -124,6 +124,21 @@ func (r *Git) Commit(files []string, msg string) (err error) {
 	return r.push()
 }
 
+// Head returns HEAD commit.
+func (r *Git) Head() (commit string, err error) {
+	cmd := command.New("/usr/bin/git")
+	cmd.Dir = r.Path
+	cmd.Options.Add("rev-parse")
+	cmd.Options.Add("HEAD")
+	err = cmd.Run()
+	if err != nil {
+		return
+	}
+	commit = string(cmd.Output())
+	commit = strings.TrimSpace(commit)
+	return
+}
+
 // push changes to remote.
 func (r *Git) push() (err error) {
 	cmd := command.New("/usr/bin/git")

repository/subversion.go

@@ -143,6 +143,12 @@ func (r *Subversion) Commit(files []string, msg string) (err error) {
 	return
 }
 
+// Head returns latest commit.
+func (r *Subversion) Head() (commit string, err error) {
+	// TODO: needs implementation.
+	return
+}
+
 // URL returns the parsed URL.
 func (r *Subversion) URL() (u *urllib.URL) {
 	u, _ = urllib.Parse(r.Remote.URL)