Make it possible to call service.Init multiple times

service.go

@@ -14,6 +14,8 @@ import (
 
 type service struct {
 	opts Options
+
+	init chan bool
 }
 
 func newService(opts ...Option) Service {
@@ -28,6 +30,7 @@ func newService(opts ...Option) Service {
 
 	return &service{
 		opts: options,
+		init: make(chan bool),
 	}
 }
 
@@ -49,7 +52,18 @@ func (s *service) run(exit chan bool) {
 	}
 }
 
+// Init initialises options. Additionally it calls cmd.Init
+// which parses command line flags. cmd.Init is only called
+// on first Init.
 func (s *service) Init(opts ...Option) {
+	// If <-s.init blocks, Init has not been called yet
+	// so we can call cmd.Init once.
+	select {
+	case <-s.init:
+	default:
+		// close init
+		close(s.init)
+
 		// We might get more command flags or the action here
 		// This is pretty ugly, find a better way
 		options := newOptions()
@@ -67,6 +81,7 @@ func (s *service) Init(opts ...Option) {
 			cmd.Client(&s.opts.Client),
 			cmd.Server(&s.opts.Server),
 		)
+	}
 
 	// Update any options to override command flags
 	for _, o := range opts {