Data server decorators implementation.

Co-authored-by: Hector Hurtado <hector.hurtado@bbva.com>

internal/server/data/decorator.go

@@ -0,0 +1,29 @@
+package data
+
+import (
+	"net/http"
+
+	"github.com/BBVA/kapow/internal/server/model"
+	"github.com/gorilla/mux"
+)
+
+type resourceHandler func(http.ResponseWriter, *http.Request, *model.Handler)
+
+func lockResponseWriter(fn resourceHandler) resourceHandler {
+	return func(w http.ResponseWriter, r *http.Request, h *model.Handler) {
+		h.Writing.Lock()
+		defer h.Writing.Unlock()
+		fn(w, r, h)
+	}
+}
+
+func checkHandler(fn resourceHandler) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		handlerID := mux.Vars(r)["handlerID"]
+		if h, ok := Handlers.Get(handlerID); ok {
+			fn(w, r, h)
+		} else {
+			w.WriteHeader(http.StatusNotFound)
+		}
+	}
+}