HEAD request for check traffic update

2 files changed, 10 insertions, 1 deletions

diff --git a/map/traffic_manager.cpp b/map/traffic_manager.cpp
index 4249316603..4e004245e3 100644
--- a/map/traffic_manager.cpp
+++ b/map/traffic_manager.cpp
@@ -227,9 +227,13 @@ void TrafficManager::ThreadRoutine()
   {
     for (auto const & mwm : mwms)
     {
+      auto const & mwmInfo = mwm.GetInfo();
+      if (!mwmInfo)
+        continue;
+
       traffic::TrafficInfo info(mwm, m_currentDataVersion);
 
-      if (info.ReceiveTrafficData())
+      if (info.ReceiveTrafficData(m_trafficETags[mwm]))
       {
         OnTrafficDataResponse(move(info));
       }
diff --git a/map/traffic_manager.hpp b/map/traffic_manager.hpp
index cf53d3091f..82a913535f 100644
--- a/map/traffic_manager.hpp
+++ b/map/traffic_manager.hpp
@@ -20,6 +20,7 @@
 #include "std/map.hpp"
 #include "std/mutex.hpp"
 #include "std/set.hpp"
+#include "std/string.hpp"
 #include "std/vector.hpp"
 
 namespace df
@@ -141,6 +142,10 @@ private:
 
   vector<MwmSet::MwmId> m_lastMwmsByRect;
   set<MwmSet::MwmId> m_activeMwms;
+  // The ETag or entity tag is part of HTTP, the protocol for the World Wide Web.
+  // It is one of several mechanisms that HTTP provides for web cache validation,
+  // which allows a client to make conditional requests.
+  map<MwmSet::MwmId, string> m_trafficETags;
 
   vector<MwmSet::MwmId> m_requestedMwms;
   mutex m_mutex;