Server|Client: Pinging the server via ServerLink and ServerInfoDialog

doomsday/apps/client/include/network/serverlink.h

@@ -38,6 +38,7 @@ class ServerLink : public de::shell::AbstractLink
 
 public:
     DENG2_DEFINE_AUDIENCE2(DiscoveryUpdate, void linkDiscoveryUpdate(ServerLink const &link))
+    DENG2_DEFINE_AUDIENCE2(PingResponse,    void pingResponse(de::Address const &, de::TimeDelta))
     DENG2_DEFINE_AUDIENCE2(MapOutline,      void mapOutlineReceived(de::Address const &, de::shell::MapOutlinePacket const &))
 
     DENG2_DEFINE_AUDIENCE2(Join,  void networkGameJoined())
@@ -89,6 +90,8 @@ class ServerLink : public de::shell::AbstractLink
 
     void requestMapOutline(de::Address const &address);
 
+    void ping(de::Address const &address);
+
     void connectDomain(de::String const &domain, de::TimeDelta const &timeout = 0) override;
     void connectHost(de::Address const &address) override;
 

doomsday/apps/client/src/network/serverlink.cpp

@@ -45,6 +45,8 @@
 #include <de/shell/ServerFinder>
 #include <doomsday/DoomsdayApp>
 #include <doomsday/Games>
+
+#include <QElapsedTimer>
 #include <QTimer>
 
 using namespace de;
@@ -53,13 +55,17 @@ enum LinkState
 {
     None,
     Discovering,
+    Pinging,
+    WaitingForPong,
     QueryingMapOutline,
     WaitingForInfoResponse,
     Joining,
     WaitingForJoinResponse,
     InGame
 };
 
+static int const NUM_PINGS = 5;
+
 DENG2_PIMPL(ServerLink)
 {
     std::unique_ptr<shell::ServerFinder> finder; ///< Finding local servers.
@@ -68,6 +74,9 @@ DENG2_PIMPL(ServerLink)
     typedef QMap<Address, shell::ServerInfo> Servers;
     Servers discovered;
     Servers fromMaster;
+    QElapsedTimer pingTimer;
+    QList<TimeDelta> pings;
+    int pingCounter;
     std::unique_ptr<GameProfile> serverProfile; ///< Profile used when joining.
     std::function<void (GameProfile const *)> profileResultCallback;
     std::function<void (Address, GameProfile const *)> profileResultCallbackWithAddress;
@@ -326,12 +335,14 @@ DENG2_PIMPL(ServerLink)
     }
 
     DENG2_PIMPL_AUDIENCE(DiscoveryUpdate)
+    DENG2_PIMPL_AUDIENCE(PingResponse)
     DENG2_PIMPL_AUDIENCE(MapOutline)
     DENG2_PIMPL_AUDIENCE(Join)
     DENG2_PIMPL_AUDIENCE(Leave)
 };
 
 DENG2_AUDIENCE_METHOD(ServerLink, DiscoveryUpdate)
+DENG2_AUDIENCE_METHOD(ServerLink, PingResponse)
 DENG2_AUDIENCE_METHOD(ServerLink, MapOutline)
 DENG2_AUDIENCE_METHOD(ServerLink, Join)
 DENG2_AUDIENCE_METHOD(ServerLink, Leave)
@@ -462,6 +473,12 @@ void ServerLink::requestMapOutline(Address const &address)
     LOG_NET_VERBOSE("Querying %s for map outline") << address;
 }
 
+void ServerLink::ping(const Address &address)
+{
+    AbstractLink::connectHost(address);
+    d->state = Pinging;
+}
+
 void ServerLink::connectDomain(String const &domain, TimeDelta const &timeout)
 {
     LOG_AS("ServerLink::connectDomain");
@@ -601,6 +618,14 @@ void ServerLink::initiateCommunications()
         d->state = WaitingForInfoResponse;
         break;
 
+    case Pinging:
+        *this << ByteRefArray("Ping?", 5);
+        d->state = WaitingForPong;
+        d->pingCounter = NUM_PINGS;
+        d->pings.clear();
+        d->pingTimer.start();
+        break;
+
     case QueryingMapOutline:
         *this << ByteRefArray("MapOutline?", 11);
         d->state = WaitingForInfoResponse;
@@ -663,6 +688,34 @@ void ServerLink::handleIncomingPackets()
             if (!d->handleJoinResponse(*packet)) return;
             break;
 
+        case WaitingForPong:
+            if (packet->size() == 4 && *packet == "Pong" &&
+                d->pingCounter-- > 0)
+            {
+                d->pings.append(TimeDelta::fromMilliSeconds(d->pingTimer.elapsed()));
+                *this << ByteRefArray("Ping?", 5);
+                d->pingTimer.restart();
+            }
+            else
+            {
+                Address const svAddress = address();
+                disconnect();
+
+                // Notify about the average ping time.
+                if (d->pings.count())
+                {
+                    TimeDelta average = 0;
+                    for (auto const &d : d->pings) average += d;
+                    average = average / d->pings.count();
+
+                    DENG2_FOR_AUDIENCE2(PingResponse, i)
+                    {
+                        i->pingResponse(svAddress, average);
+                    }
+                }
+            }
+            break;
+
         case InGame: {
             /// @todo The incoming packets should be handled immediately.
 

doomsday/apps/client/src/ui/dialogs/serverinfodialog.cpp

@@ -45,6 +45,7 @@ static DialogWidget::RoleFlags const ID_JOIN        = DialogWidget::Id2;
 
 DENG_GUI_PIMPL(ServerInfoDialog)
 , DENG2_OBSERVES(ServerLink, MapOutline)
+, DENG2_OBSERVES(ServerLink, PingResponse)
 , public PackagesWidget::IPackageStatus
 {
     // Server info & status.
@@ -60,6 +61,7 @@ DENG_GUI_PIMPL(ServerInfoDialog)
     {
         QueryNone,
         QueryStatus,
+        QueryPing,
         QueryMapOutline,
     };
     Query pendingQuery = QueryNone;
@@ -80,7 +82,8 @@ DENG_GUI_PIMPL(ServerInfoDialog)
         , serverInfo(sv)
         , link(ServerLink::ManualConnectionOnly)
     {
-        link.audienceForMapOutline() += this;
+        link.audienceForMapOutline()   += this;
+        link.audienceForPingResponse() += this;
         connect(&queryTimer, &QTimer::timeout, [this] () { beginPendingQuery(); });
 
         self().useInfoStyle();
@@ -386,6 +389,10 @@ DENG_GUI_PIMPL(ServerInfoDialog)
             }
             break;
 
+        case QueryPing:
+            link.ping(host);
+            break;
+
         case QueryMapOutline:
             link.requestMapOutline(host);
             break;
@@ -412,6 +419,12 @@ DENG_GUI_PIMPL(ServerInfoDialog)
     void mapOutlineReceived(Address const &, shell::MapOutlinePacket const &packet)
     {
         mapOutline->setOutline(packet);
+        startQuery(QueryPing);
+    }
+
+    void pingResponse(Address const &, TimeDelta pingTime)
+    {
+        qDebug() << "Ping:" << pingTime.asMilliSeconds() << "ms";
     }
 };
 

doomsday/apps/server/src/remoteuser.cpp

@@ -136,6 +136,10 @@ DENG2_PIMPL(RemoteUser)
             LOGDEV_NET_VERBOSE("Info reply:\n%s") << String::fromUtf8(msg);
             self() << msg;
         }
+        else if (command == "Ping?")
+        {
+            self() << Block("Pong");
+        }
         else if (command == "MapOutline?")
         {
             shell::MapOutlinePacket packet;