[traffic] Remove m_mwmCache and related logic

Signed-off-by: mvglasow <michael -at- vonglasow.com>

map/traffic_manager.cpp

@@ -54,6 +54,8 @@ auto constexpr kStorageUpdateInterval = minutes(1);
 auto constexpr kTrafficXMLFileName = "traffic.xml";
 } // namespace
 
+// TODO no longer needed
+#ifdef traffic_dead_code
 TrafficManager::CacheEntry::CacheEntry()
   : m_isLoaded(false)
 // TODO no longer needed
@@ -77,6 +79,7 @@ TrafficManager::CacheEntry::CacheEntry(time_point<steady_clock> const & requestT
   , m_isWaitingForResponse(true)
   , m_lastAvailability(traffic::TrafficInfo::Availability::Unknown)
 {}
+#endif
 
 TrafficManager::TrafficManager(DataSource & dataSource, CountryInfoGetterFn countryInfoGetter,
                                const CountryParentNameGetterFn &countryParentNameGetter,
@@ -193,7 +196,6 @@ void TrafficManager::Clear()
     LOG(LINFO, ("Messages in cache:", m_messageCache.size()));
     LOG(LINFO, ("Feeds in queue:", m_feedQueue.size()));
     LOG(LINFO, ("MWMs with coloring:", m_allMwmColoring.size()));
-    LOG(LINFO, ("MWM cache size:", m_mwmCache.size()));
     LOG(LINFO, ("Clearing..."));
     // TODO no longer needed
 #ifdef traffic_dead_code
@@ -201,7 +203,10 @@ void TrafficManager::Clear()
 #endif
     m_messageCache.clear();
     m_feedQueue.clear();
+// TODO no longer needed
+#ifdef traffic_dead_code
     m_mwmCache.clear();
+#endif
 
     // TODO figure out which of the ones below we still need
     m_lastDrapeMwmsByRect.clear();
@@ -214,7 +219,6 @@ void TrafficManager::Clear()
     LOG(LINFO, ("Messages in cache:", m_messageCache.size()));
     LOG(LINFO, ("Feeds in queue:", m_feedQueue.size()));
     LOG(LINFO, ("MWMs with coloring:", m_allMwmColoring.size()));
-    LOG(LINFO, ("MWM cache size:", m_mwmCache.size()));
   }
   OnTrafficDataUpdate();
 }
@@ -318,7 +322,7 @@ void TrafficManager::OnChangeRoutingSessionState(routing::SessionState previous,
     {
       m_activeMwmsChanged = true;
       std::swap(mwms, m_activeRoutingMwms);
-      RequestTrafficData();
+      RequestTrafficSubscription();
     }
   }
 }
@@ -405,7 +409,7 @@ void TrafficManager::UpdateActiveMwms(m2::RectD const & rect,
       if (mwm.IsAlive())
         activeMwms.insert(mwm);
     }
-    RequestTrafficData();
+    RequestTrafficSubscription();
   }
 }
 
@@ -835,40 +839,7 @@ bool TrafficManager::WaitForRequest()
   return true;
 }
 
-void TrafficManager::RequestTrafficData(MwmSet::MwmId const & mwmId, bool force)
+void TrafficManager::RequestTrafficSubscription()
-{
-  bool needRequesting = false;
-  auto const currentTime = steady_clock::now();
-  auto const it = m_mwmCache.find(mwmId);
-  if (it == m_mwmCache.end())
-  {
-    needRequesting = true;
-    m_mwmCache.insert(std::make_pair(mwmId, CacheEntry(currentTime)));
-  }
-  else
-  {
-    auto const passedSeconds = currentTime - it->second.m_lastRequestTime;
-    if (passedSeconds >= kUpdateInterval || force)
-    {
-      needRequesting = true;
-      it->second.m_isWaitingForResponse = true;
-      it->second.m_lastRequestTime = currentTime;
-    }
-    if (!force)
-      it->second.m_lastActiveTime = currentTime;
-  }
-
-  if (needRequesting)
-  {
-// TODO no longer needed
-#ifdef traffic_dead_code
-    m_requestedMwms.push_back(mwmId);
-#endif
-    m_condition.notify_one();
-  }
-}
-
-void TrafficManager::RequestTrafficData()
 {
   if ((m_activeDrapeMwms.empty() && m_activePositionMwms.empty() && m_activeRoutingMwms.empty())
       || !IsEnabled() || IsInvalidState() || m_isPaused)
@@ -878,9 +849,17 @@ void TrafficManager::RequestTrafficData()
 
   ForEachActiveMwm([this](MwmSet::MwmId const & mwmId) {
     ASSERT(mwmId.IsAlive(), ());
-    RequestTrafficData(mwmId, false /* force */);
+// TODO no longer needed
+#ifdef traffic_dead_code
+    m_mwmCache.insert(mwmId);
+#endif
   });
+  m_condition.notify_one();
+
+// TODO no longer needed
+#ifdef traffic_dead_code
   UpdateState();
+#endif
 }
 
 // TODO no longer needed
@@ -982,13 +961,12 @@ void TrafficManager::OnTrafficDataUpdate()
   /*
    * Much of this code is copied and pasted together from old MWM code, with some minor adaptations:
    *
-   * ForEachActiveMwm and the assertion (not the rest of the body) is from RequestTrafficData();
+   * ForEachActiveMwm and the assertion (not the rest of the body) is from RequestTrafficData()
-   * modification: cycle over all MWMs (active or not).
+   * (now RequestTrafficSubscription()), modification: cycle over all MWMs (active or not).
    * trafficCache lookup is original code.
    * TrafficInfo construction is taken fron ThreadRoutine(), with modifications (different constructor).
-   * Updating m_mwmCache is from RequestTrafficData(MwmSet::MwmId const &, bool), with modifications.
    * The remainder of the loop is from OnTrafficDataResponse(traffic::TrafficInfo &&), with some modifications
-   * (deciding whether to notify a component and managing timestamps is original code).
+   * (removed CacheEntry logic; deciding whether to notify a component and managing timestamps is original code).
    * Existing coloring deletion (if there is no new coloring) is original code.
    */
   ForEachMwm([this, notifyDrape, notifyObserver](std::shared_ptr<MwmInfo> info) {
@@ -1007,17 +985,10 @@ void TrafficManager::OnTrafficDataUpdate()
       LOG(LINFO, ("Setting new coloring for", mwmId, "with", coloring.size(), "entries"));
       traffic::TrafficInfo info(mwmId, std::move(coloring));
 
-      m_mwmCache.try_emplace(mwmId, CacheEntry(steady_clock::now()));
+// TODO no longer needed
-
+#ifdef traffic_dead_code
-      auto it = m_mwmCache.find(mwmId);
-      if (it != m_mwmCache.end())
-      {
-        it->second.m_isLoaded = true;
-        it->second.m_lastResponseTime = steady_clock::now();
-        it->second.m_isWaitingForResponse = false;
-        it->second.m_lastAvailability = info.GetAvailability();
-
       UpdateState();
+#endif
 
       if (notifyDrape)
       {
@@ -1044,7 +1015,6 @@ void TrafficManager::OnTrafficDataUpdate()
         m_lastObserverUpdate = steady_clock::now();
       }
     }
-    }
     else
     {
       if (notifyDrape)
@@ -1181,6 +1151,8 @@ bool TrafficManager::IsInvalidState() const
   return m_state == TrafficState::NetworkError;
 }
 
+// TODO no longer needed
+#ifdef traffic_dead_code
 void TrafficManager::UpdateState()
 {
   if (!IsEnabled() || IsInvalidState())
@@ -1238,6 +1210,7 @@ void TrafficManager::UpdateState()
   else
     ChangeState(TrafficState::Enabled);
 }
+#endif
 
 void TrafficManager::ChangeState(TrafficState newState)
 {

map/traffic_manager.hpp

@@ -46,6 +46,7 @@ public:
   /**
    * @brief Global state of traffic information.
    */
+  // TODO apart from `Disabled` and `Enabled`, all states are obsolete
   enum class TrafficState
   {
     /** Traffic is disabled, no traffic data will be retrieved or considered for routing. */
@@ -294,6 +295,8 @@ public:
   void Clear();
 
 private:
+// TODO no longer needed
+#ifdef traffic_dead_code
   /**
    * @brief Holds information about pending or previous traffic requests pertaining to an MWM.
    */
@@ -307,13 +310,10 @@ private:
      */
     bool m_isLoaded;
 
-// TODO no longer needed
-#ifdef traffic_dead_code
     /**
      * @brief The amount of memory occupied by the coloring for this MWM.
      */
     size_t m_dataSize;
-#endif
 
     /**
      * @brief When the last update request occurred, not including forced updates.
@@ -352,6 +352,7 @@ private:
 
     traffic::TrafficInfo::Availability m_lastAvailability;
   };
+#endif
 
   /**
    * @brief Ensures every TraFF source has a subscription covering all currently active MWMs.
@@ -466,7 +467,7 @@ private:
    * If the MWM is no longer active, this method returns immediately after that.
    *
    * If the retry limit has not been reached, the MWM is re-inserted into the list by calling
-   * `RequestTrafficData(MwmSet::MwmId, bool)` with `force` set to true. Otherwise, the retry count
+   * `RequestTrafficSubscription(MwmSet::MwmId, bool)` with `force` set to true. Otherwise, the retry count
    * is reset and the state updated accordingly.
    *
    * @param info
@@ -498,12 +499,9 @@ private:
   // This is a group of methods that haven't their own synchronization inside.
 
   /**
-   * @brief Requests a refresh of traffic data for all currently active MWMs.
+   * @brief Requests a refresh of traffic subscriptions to match all currently active MWMs.
    *
-   * This method is the entry point for periodic traffic data refresh operations. It cycles through
+   * The actual call to the TraFF sources is performed asynchronously on a separate thread.
-   * all active MWMs and calls `RequestTrafficData(MwmSet::MwmId, bool)` on each `MwmId`,
-   * scheduling a refresh if needed. The actual network operation is performed asynchronously on a
-   * separate thread.
    *
    * The method does nothing if the `TrafficManager` instance is disabled, paused, in an invalid
    * state (`NetworkError`) or if neither the rendering engine nor the routing engine have any
@@ -511,22 +509,7 @@ private:
    *
    * This method is unsynchronized; the caller must lock `m_mutex` prior to calling it.
    */
-  void RequestTrafficData();
+  void RequestTrafficSubscription();
-
-  /**
-   * @brief Requests a refresh of traffic data for a single MWM.
-   *
-   * This method first checks if traffic data for the given MWM needs to be refreshed, which is the
-   * case if no traffic data has ever been fetched for the given MWM, the update interval has
-   * expired or `force` is true. In that case, the method inserts the `mwmId` into the list of MWMs
-   * for which to update traffic and wakes up the worker thread.
-   *
-   * This method is unsynchronized; the caller must lock `m_mutex` prior to calling it.
-   *
-   * @param mwmId Describes the MWM for which traffic data is to be refreshed.
-   * @param force If true, a refresh is requested even if the update interval has not expired.
-   */
-  void RequestTrafficData(MwmSet::MwmId const & mwmId, bool force);
 
 // TODO no longer needed
 #ifdef traffic_dead_code
@@ -543,7 +526,6 @@ private:
    */
   void ClearCache(MwmSet::MwmId const & mwmId);
   void ShrinkCacheToAllowableSize();
-#endif
 
   /**
    * @brief Updates the state of the traffic manager based on the state of all MWMs used by the renderer.
@@ -558,6 +540,7 @@ private:
    * `TrafficState::NoData`, `TrafficState::Outdated`, `TrafficState::Enabled`.
    */
   void UpdateState();
+#endif
   void ChangeState(TrafficState newState);
 
   bool IsInvalidState() const;
@@ -638,9 +621,9 @@ private:
 #ifdef traffic_dead_code
   size_t m_maxCacheSizeBytes;
   size_t m_currentCacheSizeBytes = 0;
-#endif
 
   std::map<MwmSet::MwmId, CacheEntry> m_mwmCache;
+#endif
 
   /**
    * @brief The TraFF sources from which we get traffic information.
@@ -666,9 +649,9 @@ private:
    *
    * Methods which use only the set:
    *
-   * * RequestTrafficData(), exits if empty, otherwise cycles through the set.
+   * * RequestTrafficSubscription(), exits if empty, otherwise cycles through the set.
    * * OnTrafficRequestFailed(), determines if an MWM is still active and the request should be retried.
-   * * UniteActiveMwms(), build the list of active MWMs (used by RequestTrafficData() or to shrink the cache).
+   * * UniteActiveMwms(), build the list of active MWMs (used by RequestTrafficSubscription() or to shrink the cache).
    * * UpdateState(), cycles through the set to determine the state of traffic requests (renderer only).
    *
    * Methods which use both, but in a different way: