[Chromoting] Add SessionPlugin in JingleSession

remoting/protocol/jingle_session.cc

Index: remoting/protocol/jingle_session.cc
diff --git a/remoting/protocol/jingle_session.cc b/remoting/protocol/jingle_session.cc
index f421b025e6716af41571af663bc24fefa1568f53..746a4e2cb032d12f6d72acaf9ae29dc019c7cf95 100644
--- a/remoting/protocol/jingle_session.cc
+++ b/remoting/protocol/jingle_session.cc
@@ -7,6 +7,7 @@
 #include <stdint.h>
 
 #include <limits>
+#include <memory>
 #include <utility>
 
 #include "base/bind.h"
@@ -21,6 +22,7 @@
 #include "remoting/protocol/jingle_messages.h"
 #include "remoting/protocol/jingle_session_manager.h"
 #include "remoting/protocol/session_config.h"
+#include "remoting/protocol/session_plugin.h"
 #include "remoting/protocol/transport.h"
 #include "remoting/signaling/iq_sender.h"
 #include "third_party/webrtc/libjingle/xmllite/xmlelement.h"
@@ -249,6 +251,7 @@ void JingleSession::AcceptIncomingConnection(
     const JingleMessage& initiate_message) {
   DCHECK(config_);
 
+  ExecutePluginsOnIncomingMessage(initiate_message);
   // Process the first authentication message.
   const buzz::XmlElement* first_auth_message =
       initiate_message.description->authenticator_message();
@@ -322,6 +325,7 @@ void JingleSession::SendTransportInfo(
   std::unique_ptr<JingleMessage> message(new JingleMessage(
       peer_address_, JingleMessage::TRANSPORT_INFO, session_id_));
   message->transport_info = std::move(transport_info);
+  ExecutePluginsOnOutgoingMessage(message.get());
 
   std::unique_ptr<buzz::XmlElement> stanza = message->ToXml();
   stanza->AddAttr(buzz::QN_ID, GetNextOutgoingId());
@@ -386,9 +390,15 @@ void JingleSession::Close(protocol::ErrorCode error) {
   }
 }
 
+void JingleSession::Attach(std::unique_ptr<SessionPlugin> plugin) {
+  DCHECK(plugin);
+  plugins_.push_back(std::move(plugin));
+}
+
 void JingleSession::SendMessage(std::unique_ptr<JingleMessage> message) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
+  ExecutePluginsOnOutgoingMessage(message.get());
   std::unique_ptr<buzz::XmlElement> stanza = message->ToXml();
   stanza->AddAttr(buzz::QN_ID, GetNextOutgoingId());
 
@@ -482,6 +492,8 @@ void JingleSession::OnTransportInfoResponse(IqRequest* request,
 void JingleSession::OnIncomingMessage(const std::string& id,
                                       std::unique_ptr<JingleMessage> message,
                                       const ReplyCallback& reply_callback) {
+  DCHECK(message);

[Sergey Ulanov, 2016/12/21 01:38:34]

Don't really need this. unique_ptr<>::operator* called in the next line will
assert that the pointer is not null. 

[Hzj_jie, 2016/12/22 00:27:10]

Done.

+  ExecutePluginsOnIncomingMessage(*message);
   std::vector<PendingMessage> ordered = message_queue_->OnIncomingMessage(
       id, PendingMessage{std::move(message), reply_callback});
   base::WeakPtr<JingleSession> self = weak_factory_.GetWeakPtr();
@@ -747,6 +759,20 @@ bool JingleSession::is_session_active() {
         state_ == AUTHENTICATING || state_ == AUTHENTICATED;
 }
 
+void JingleSession::ExecutePluginsOnIncomingMessage(

[Sergey Ulanov, 2016/12/21 01:38:34]

I don't think you really need this function. It's executed in only one place and
it is 3 lines long.

[Hzj_jie, 2016/12/22 00:27:10]

Not really, this function is called by both AcceptIncomingConnection() and
OnIncomingMessage().

+    const JingleMessage& message) {
+  for (const auto& plugin : plugins_) {
+    plugin->OnIncoming(state_, message.action, message.attachments.get());
+  }
+}
+
+void JingleSession::ExecutePluginsOnOutgoingMessage(JingleMessage* message) {
+  DCHECK(message);
+  for (const auto& plugin : plugins_) {
+    message->AttachAttachment(plugin->OnOutgoing(state_, message->action));
+  }
+}
+
 std::string JingleSession::GetNextOutgoingId() {
   return outgoing_id_prefix_ + "_" + base::IntToString(++next_outgoing_id_);
 }