1 files changed, 46 insertions, 0 deletions
diff --git a/service/watcher/service.go b/service/watcher/service.go
new file mode 100644
index 00000000..c81ff3f5
--- /dev/null
+++ b/service/watcher/service.go
@@ -0,0 +1,46 @@
+package watcher
+
+import (
+	"github.com/spiral/roadrunner"
+	"github.com/spiral/roadrunner/service"
+)
+
+// ID defines watcher service name.
+const ID = "watch"
+
+// Watchable defines the ability to attach roadrunner watcher.
+type Watchable interface {
+	// Watch attaches watcher to the service.
+	Watch(w roadrunner.Watcher)
+}
+
+// Services to watch the state of roadrunner service inside other services.
+type Service struct {
+	cfg  *Config
+	lsns []func(event int, ctx interface{})
+}
+
+// Init watcher service
+func (s *Service) Init(cfg *Config, c service.Container) (bool, error) {
+	// mount Services to designated services
+	for id, watcher := range cfg.Watchers(s.throw) {
+		svc, _ := c.Get(id)
+		if watchable, ok := svc.(Watchable); ok {
+			watchable.Watch(watcher)
+		}
+	}
+
+	return true, nil
+}
+
+// AddListener attaches server event watcher.
+func (s *Service) AddListener(l func(event int, ctx interface{})) {
+	s.lsns = append(s.lsns, l)
+}
+
+// throw handles service, server and pool events.
+func (s *Service) throw(event int, ctx interface{}) {
+	for _, l := range s.lsns {
+		l(event, ctx)
+	}
+}