add cors option

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

http.go

@@ -35,6 +35,7 @@ type Server struct {
 	pathHandlers *rhttp.Trie
 	opts         server.Options
 	registerRPC  bool
+	registerCORS bool
 	sync.RWMutex
 	registered bool
 	init       bool
@@ -84,6 +85,10 @@ func (h *Server) Init(opts ...server.Option) error {
 		h.registerRPC = v
 	}
 
+	if v, ok := h.opts.Context.Value(registerCORSHandlerKey{}).(bool); ok {
+		h.registerCORS = v
+	}
+
 	if phs, ok := h.opts.Context.Value(pathHandlerKey{}).(*pathHandlerVal); ok && phs.h != nil {
 		for pm, ps := range phs.h {
 			for pp, ph := range ps {
@@ -227,6 +232,13 @@ func (h *Server) NewHandler(handler interface{}, opts ...server.HandlerOption) s
 			h.opts.Logger.Errorf(h.opts.Context, "cant add handler for %s %s", md["Method"], md["Path"])
 		}
 
+		if h.registerCORS {
+			h.opts.Logger.Infof(h.opts.Context, "register cors handler for http.MethodOptions %s /%s", hn, hn)
+			if err := hdlr.handlers.Insert([]string{http.MethodOptions}, "/"+hn, pth); err != nil {
+				h.opts.Logger.Errorf(h.opts.Context, "cant add rpc handler for http.MethodOptions %s /%s", hn, hn)
+			}
+		}
+
 		if h.registerRPC {
 			h.opts.Logger.Infof(h.opts.Context, "register rpc handler for http.MethodPost %s /%s", hn, hn)
 			if err := hdlr.handlers.Insert([]string{http.MethodPost}, "/"+hn, pth); err != nil {