From c1e0ce26b57c8d7bb5f355c373456a45f493de3c Mon Sep 17 00:00:00 2001
From: Vasiliy Tolstov <v.tolstov@unistack.org>
Date: Wed, 14 Jul 2021 13:43:45 +0300
Subject: [PATCH] add ability to register RPC endpoint

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
---
 handler.go |  1 +
 http.go    | 24 ++++++++++++++++++++++++
 options.go |  7 +++++++
 3 files changed, 32 insertions(+)

diff --git a/handler.go b/handler.go
index 102cf13..506383a 100644
--- a/handler.go
+++ b/handler.go
@@ -123,6 +123,7 @@ func (h *httpServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	var match bool
 	var hldr patHandler
 	var handler *httpHandler
+
 	for _, hpat := range h.handlers {
 		handlertmp := hpat.(*httpHandler)
 		for _, hldrtmp := range handlertmp.handlers[r.Method] {
diff --git a/http.go b/http.go
index 2e31f4d..e36b80c 100644
--- a/http.go
+++ b/http.go
@@ -33,6 +33,7 @@ type httpServer struct {
 	pathHandlers        map[*regexp.Regexp]http.HandlerFunc
 	contentTypeHandlers map[string]http.HandlerFunc
 	opts                server.Options
+	registerRPC         bool
 	sync.RWMutex
 	registered bool
 	init       bool
@@ -80,6 +81,11 @@ func (h *httpServer) Init(opts ...server.Option) error {
 	if h.contentTypeHandlers == nil {
 		h.contentTypeHandlers = make(map[string]http.HandlerFunc)
 	}
+
+	if v, ok := h.opts.Context.Value(registerRPCHandlerKey{}).(bool); ok {
+		h.registerRPC = v
+	}
+
 	if phs, ok := h.opts.Context.Value(pathHandlerKey{}).(*pathHandlerVal); ok && phs.h != nil {
 		for pp, ph := range phs.h {
 			exp, err := regexp.Compile(pp)
@@ -240,6 +246,24 @@ func (h *httpServer) NewHandler(handler interface{}, opts ...server.HandlerOptio
 		pth := patHandler{pat: pat, mtype: mtype, name: name, rcvr: rcvr}
 		hdlr.name = name
 		hdlr.handlers[md["Method"]] = append(hdlr.handlers[md["Method"]], pth)
+
+		if !h.registerRPC {
+			continue
+		}
+
+		cmp, err = rutil.Parse("/" + hn)
+		if err != nil && h.opts.Logger.V(logger.ErrorLevel) {
+			h.opts.Logger.Errorf(h.opts.Context, "parsing path pattern err: %v", err)
+			continue
+		}
+		tpl = cmp.Compile()
+		pat, err = rutil.NewPattern(tpl.Version, tpl.OpCodes, tpl.Pool, tpl.Verb)
+		if err != nil && h.opts.Logger.V(logger.ErrorLevel) {
+			h.opts.Logger.Errorf(h.opts.Context, "creating new pattern err: %v", err)
+			continue
+		}
+		pth = patHandler{pat: pat, mtype: mtype, name: name, rcvr: rcvr}
+		hdlr.handlers[http.MethodPost] = append(hdlr.handlers[http.MethodPost], pth)
 	}
 
 	return hdlr
diff --git a/options.go b/options.go
index 4173e5a..7b01d5c 100644
--- a/options.go
+++ b/options.go
@@ -110,3 +110,10 @@ func ContentTypeHandler(ct string, h http.HandlerFunc) server.Option {
 		o.Context = context.WithValue(o.Context, contentTypeHandlerKey{}, v)
 	}
 }
+
+type registerRPCHandlerKey struct{}
+
+// RegisterRPCHandler registers compatibility endpoints with /ServiceName.ServiceEndpoint method POST
+func RegisterRPCHandler(b bool) server.Option {
+	return server.SetOption(registerRPCHandlerKey{}, b)
+}