Create MediaSession in main function.

Author: jianjunz

talk/owt/sdk/wasm/binding.h

@@ -5,7 +5,6 @@
 #ifndef OWT_WASM_BINDING_H_
 #define OWT_WASM_BINDING_H_
 
-#include <emscripten/bind.h>
 #include "talk/owt/sdk/wasm/media_session.h"
 #include "talk/owt/sdk/wasm/rtp_video_receiver.h"
 
@@ -14,9 +13,11 @@ namespace wasm {
 
 EMSCRIPTEN_BINDINGS(Owt) {
   emscripten::class_<MediaSession>("MediaSession")
-      .constructor<>()
+      .smart_ptr<std::shared_ptr<MediaSession>>("MediaSession")
       .function("createRtpVideoReceiver", &MediaSession::CreateRtpVideoReceiver)
-      .function("setRtcpCallback", &MediaSession::SetRtcpCallback);
+      .function("setRtcpCallback", &MediaSession::SetRtcpCallback)
+      .class_function("get", &MediaSession::Get,
+                      emscripten::allow_raw_pointers());
   emscripten::class_<RtpVideoReceiver>("RtpVideoReceiver")
       .smart_ptr<std::shared_ptr<RtpVideoReceiver>>("RtpVideoReceiver")
       .function("onRtpPacket", &RtpVideoReceiver::OnRtpPacket,

talk/owt/sdk/wasm/main.cc

@@ -2,17 +2,10 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-#include <emscripten/bind.h>
 #include <iostream>
-#include "third_party/webrtc/rtc_base/strings/json.h"
 #include "talk/owt/sdk/wasm/binding.h"
 
 int main(int argc, char** argv) {
-  Json::Value in_s("foo");
-  std::string out;
-  rtc::GetStringFromJson(in_s, &out);
-  std::cout << out << std::endl;
-
-  printf("WASM main.\n");
+  owt::wasm::MediaSession::Get();
   return 0;
 }

talk/owt/sdk/wasm/media_session.cc

@@ -9,6 +9,7 @@
 
 namespace owt {
 namespace wasm {
+
 MediaSession::MediaSession()
     : task_queue_factory_(webrtc::CreateTaskQueueStdlibFactory()),
       event_log_factory_(std::make_unique<webrtc::RtcEventLogFactory>(
@@ -50,6 +51,16 @@ std::shared_ptr<RtpVideoReceiver> MediaSession::CreateRtpVideoReceiver(
   return video_receiver_;
 }
 
+std::once_flag create_media_session_flag;
+std::shared_ptr<MediaSession> media_session;
+
+MediaSession* MediaSession::Get() {
+  std::call_once(create_media_session_flag,
+                 [] { media_session = std::make_shared<MediaSession>(); });
+  return media_session.get();
+}
+
+
 void MediaSession::SetRtcpCallback(emscripten::val callback) {
   rtcp_callback_ = callback;
 }

talk/owt/sdk/wasm/media_session.h

@@ -18,6 +18,9 @@ class MediaSession : public webrtc::Transport {
  public:
   explicit MediaSession();
   virtual ~MediaSession() = default;
+
+  static MediaSession* Get();
+
   std::shared_ptr<RtpVideoReceiver> CreateRtpVideoReceiver(
       uint32_t remote_ssrc);
   void SetRtcpCallback(emscripten::val callback);