Add events buffering logic

ClientLib/build.gradle

@@ -5,7 +5,7 @@ ext {
     VERSION_MAJOR = 3
     VERSION_MINOR = 0
     VERSION_PATCH = 0
-    VERSION_SUFFIX = "alpha5"
+    VERSION_SUFFIX = "alpha6"
 
     PUBLISH_ARTIFACT_ID = 'dronekit-android'
     PUBLISH_VERSION = generateVersionName("", VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH, VERSION_SUFFIX)

ClientLib/src/main/java/org/droidplanner/services/android/impl/api/DroidPlannerService.java

@@ -133,7 +133,7 @@ DroneManager connectDroneManager(ConnectionParameter connParams, String appId, D
         }
 
         Timber.d("Drone manager connection for " + appId);
-        droneMgr.connect(appId, listener, connParams.getTLogLoggingUri());
+        droneMgr.connect(appId, listener, connParams);
         return droneMgr;
     }
 

ClientLib/src/main/java/org/droidplanner/services/android/impl/api/DroneApi.java

@@ -3,7 +3,9 @@
 import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
+import android.os.Handler;
 import android.os.IBinder;
+import android.os.Looper;
 import android.os.RemoteException;
 import android.text.TextUtils;
 import android.util.Pair;
@@ -54,8 +56,11 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.NoSuchElementException;
+import java.util.Set;
 import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.ConcurrentSkipListMap;
 
 import timber.log.Timber;
 
@@ -68,7 +73,29 @@ public final class DroneApi extends IDroneApi.Stub implements DroneInterfaces.On
     //The Reset ROI mission item was introduced in version 2.6.8. Any client library older than this do not support it.
     private final static int RESET_ROI_LIB_VERSION = 206080;
 
+    private final Runnable eventsDispatcher = new Runnable() {
+        @Override
+        public void run() {
+            handler.removeCallbacks(this);
+
+            //Go through the events buffer and empty it
+            Set<Map.Entry<EventInfo, Bundle>> eventsToDispatch = eventsBuffer.entrySet();
+            for(Map.Entry<EventInfo, Bundle> entry: eventsToDispatch){
+                String event = entry.getKey().event;
+                Bundle extras = entry.getValue();
+                eventsToDispatch.remove(entry);
+                dispatchAttributeEvent(event, extras);
+            }
+
+            if(isEventsBufferingEnabled()) {
+                handler.postDelayed(this, connectionParams.getEventsDispatchingPeriod());
+            }
+        }
+    };
+
     private final Context context;
+    private final Handler handler;
+    private final Bundle emptyBundle = Bundle.EMPTY;
 
     private final ConcurrentLinkedQueue<IObserver> observersList;
     private final ConcurrentLinkedQueue<IMavlinkObserver> mavlinkObserversList;
@@ -80,12 +107,15 @@ public final class DroneApi extends IDroneApi.Stub implements DroneInterfaces.On
 
     private final DroidPlannerService service;
 
+    private final Map<EventInfo, Bundle> eventsBuffer = new ConcurrentSkipListMap<>();
+
     private ConnectionParameter connectionParams;
 
     DroneApi(DroidPlannerService dpService, IApiListener listener, String ownerId) {
 
         this.service = dpService;
         this.context = dpService.getApplicationContext();
+        handler = new Handler(Looper.getMainLooper());
 
         this.ownerId = ownerId;
 
@@ -139,6 +169,10 @@ private Drone getDrone() {
         return this.droneMgr.getDrone();
     }
 
+    private boolean isEventsBufferingEnabled(){
+        return connectionParams != null && connectionParams.getEventsDispatchingPeriod() > 0L;
+    }
+
     @Override
     public Bundle getAttribute(String type) throws RemoteException {
         Bundle carrier = new Bundle();
@@ -218,6 +252,10 @@ public void connect(ConnectionParameter connParams) {
 
                 this.connectionParams = connParams;
                 this.droneMgr = service.connectDroneManager(this.connectionParams, ownerId, this);
+
+                if(isEventsBufferingEnabled()) {
+                    handler.postDelayed(eventsDispatcher, this.connectionParams.getEventsDispatchingPeriod());
+                }
             }
         } catch (ConnectionException e) {
             LinkConnectionStatus connectionStatus = LinkConnectionStatus
@@ -232,6 +270,8 @@ public void disconnect() {
         this.connectionParams = null;
         this.droneMgr = null;
 
+        handler.removeCallbacks(eventsDispatcher);
+
     }
 
     private void checkForSelfRelease() {
@@ -385,21 +425,36 @@ private void notifyAttributeUpdate(List<Pair<String, Bundle>> attributesInfo) {
     }
 
     private void notifyAttributeUpdate(String attributeEvent, Bundle extrasBundle) {
-        if (observersList.isEmpty()) {
+        if (observersList.isEmpty() || attributeEvent == null) {
             return;
         }
 
-        if (attributeEvent != null) {
-            for (IObserver observer : observersList) {
+        if(AttributeEvent.STATE_CONNECTED.equals(attributeEvent) ||
+            AttributeEvent.STATE_DISCONNECTED.equals(attributeEvent) ||
+            !isEventsBufferingEnabled()){
+            //Dispatch the event immediately
+            dispatchAttributeEvent(attributeEvent, extrasBundle);
+        }
+        else{
+            if(extrasBundle == null)
+                extrasBundle = emptyBundle;
+            eventsBuffer.put(new EventInfo(attributeEvent), extrasBundle);
+        }
+    }
+
+    private void dispatchAttributeEvent(String attributeEvent, Bundle extrasBundle){
+        if(extrasBundle == emptyBundle)
+            extrasBundle = null;
+
+        for (IObserver observer : observersList) {
+            try {
+                observer.onAttributeUpdated(attributeEvent, extrasBundle);
+            } catch (RemoteException e) {
+                Timber.e(e, e.getMessage());
                 try {
-                    observer.onAttributeUpdated(attributeEvent, extrasBundle);
-                } catch (RemoteException e) {
-                    Timber.e(e, e.getMessage());
-                    try {
-                        removeAttributesObserver(observer);
-                    } catch (RemoteException e1) {
-                        Timber.e(e, e1.getMessage());
-                    }
+                    removeAttributesObserver(observer);
+                } catch (RemoteException e1) {
+                    Timber.e(e, e1.getMessage());
                 }
             }
         }
@@ -735,4 +790,42 @@ public ClientInfo(String appId, int apiVersionCode, int clientVersionCode) {
             this.clientVersionCode = clientVersionCode;
         }
     }
+
+    private static class EventInfo implements Comparable<EventInfo>{
+        final String event;
+        final long eventTimestamp;
+
+        EventInfo(String event){
+            this.event = event;
+            eventTimestamp = System.currentTimeMillis();
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (!(o instanceof EventInfo)) {
+                return false;
+            }
+
+            EventInfo eventInfo = (EventInfo) o;
+
+            return event != null ? event.equals(eventInfo.event) : eventInfo.event == null;
+
+        }
+
+        @Override
+        public int hashCode() {
+            return event != null ? event.hashCode() : 0;
+        }
+
+        @Override
+        public int compareTo(EventInfo another) {
+            if(this.event.equals(another.event))
+                return 0;
+
+            return this.eventTimestamp > another.eventTimestamp ? 1 : -1;
+        }
+    }
 }

ClientLib/src/main/java/org/droidplanner/services/android/impl/core/drone/DroneEvents.java

@@ -1,53 +1,19 @@
 package org.droidplanner.services.android.impl.core.drone;
 
-import android.os.Handler;
-
 import org.droidplanner.services.android.impl.core.drone.DroneInterfaces.DroneEventsType;
 import org.droidplanner.services.android.impl.core.drone.DroneInterfaces.OnDroneListener;
 import org.droidplanner.services.android.impl.core.drone.autopilot.MavLinkDrone;
 
 import java.util.concurrent.ConcurrentLinkedQueue;
-import java.util.concurrent.atomic.AtomicBoolean;
 
 public class DroneEvents extends DroneVariable<MavLinkDrone> {
 
-    private static final long EVENT_DISPATCHING_DELAY = 33l; //milliseconds
-
-    private final AtomicBoolean isDispatcherRunning = new AtomicBoolean(false);
-
-    private final Runnable eventDispatcher = new Runnable() {
-
-        @Override
-        public void run() {
-            handler.removeCallbacks(this);
-
-            final DroneEventsType event = eventQueue.poll();
-            if (event == null) {
-                isDispatcherRunning.set(false);
-                return;
-            }
-
-            for (OnDroneListener listener : droneListeners) {
-                listener.onDroneEvent(event, myDrone);
-            }
-
-            handler.removeCallbacks(this);
-            handler.postDelayed(this, EVENT_DISPATCHING_DELAY);
-
-            isDispatcherRunning.set(true);
-        }
-    };
-
-    private final Handler handler;
+    private final ConcurrentLinkedQueue<OnDroneListener> droneListeners = new ConcurrentLinkedQueue<OnDroneListener>();
 
-    public DroneEvents(MavLinkDrone myDrone, Handler handler) {
+    public DroneEvents(MavLinkDrone myDrone) {
         super(myDrone);
-        this.handler = handler;
     }
 
-    private final ConcurrentLinkedQueue<OnDroneListener> droneListeners = new ConcurrentLinkedQueue<OnDroneListener>();
-    private final ConcurrentLinkedQueue<DroneEventsType> eventQueue = new ConcurrentLinkedQueue<>();
-
     public void addDroneListener(OnDroneListener listener) {
         if (listener != null & !droneListeners.contains(listener))
             droneListeners.add(listener);
@@ -63,11 +29,11 @@ public void removeAllDroneListeners(){
     }
 
     public void notifyDroneEvent(DroneEventsType event) {
-        if (event == null || droneListeners.isEmpty() || eventQueue.contains(event))
+        if (event == null || droneListeners.isEmpty())
             return;
 
-        eventQueue.add(event);
-        if (isDispatcherRunning.compareAndSet(false, true))
-            handler.postDelayed(eventDispatcher, EVENT_DISPATCHING_DELAY);
+        for (OnDroneListener listener : droneListeners) {
+            listener.onDroneEvent(event, myDrone);
+        }
     }
 }

ClientLib/src/main/java/org/droidplanner/services/android/impl/core/drone/DroneManager.java

@@ -1,10 +1,8 @@
 package org.droidplanner.services.android.impl.core.drone;
 
 import android.content.Context;
-import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
-import android.support.annotation.Nullable;
 import android.text.TextUtils;
 import android.util.Log;
 
@@ -79,16 +77,16 @@ public void destroy() {
 
     }
 
-    public synchronized void connect(String appId, DroneApi listener, Uri tlogLoggingUri) {
+    public synchronized void connect(String appId, DroneApi listener, ConnectionParameter connParams) {
         if (listener == null || TextUtils.isEmpty(appId)) {
             return;
         }
 
         connectedApps.put(appId, listener);
-        doConnect(appId, listener, tlogLoggingUri);
+        doConnect(appId, listener, connParams);
     }
 
-    protected void doConnect(String appId, DroneApi listener, @Nullable Uri tlogLoggingUri) {
+    protected void doConnect(String appId, DroneApi listener, ConnectionParameter connParams) {
 
     }
 

ClientLib/src/main/java/org/droidplanner/services/android/impl/core/drone/autopilot/generic/GenericMavLinkDrone.java

@@ -73,7 +73,6 @@
 import org.droidplanner.services.android.impl.core.mission.Mission;
 import org.droidplanner.services.android.impl.core.model.AutopilotWarningParser;
 import org.droidplanner.services.android.impl.utils.CommonApiUtils;
-import org.droidplanner.services.android.impl.utils.prefs.DroidPlannerPrefs;
 import org.droidplanner.services.android.impl.utils.video.VideoManager;
 
 /**
@@ -121,7 +120,7 @@ public GenericMavLinkDrone(String droneId, Context context, Handler handler, Dat
 
         this.logListener = logListener;
 
-        events = new DroneEvents(this, handler);
+        events = new DroneEvents(this);
         heartbeat = initHeartBeat(handler);
         this.type = new Type(this);
         this.missionStats = new MissionStats(this);
@@ -418,11 +417,11 @@ public boolean executeAsyncAction(Action action, ICommandListener listener) {
     private boolean updateVehicleDataStreamRate(Bundle data, ICommandListener listener) {
         StreamRates streamRates = getStreamRates();
         if(streamRates != null){
-            int rate = data.getInt(StateActions.EXTRA_VEHICLE_DATA_STREAM_RATE, DroidPlannerPrefs.DEFAULT_STREAM_RATE);
-            StreamRates.Rates rates = new StreamRates.Rates(rate);
-            streamRates.setRates(rates);
-
-            streamRates.setupStreamRatesFromPref();
+            int rate = data.getInt(StateActions.EXTRA_VEHICLE_DATA_STREAM_RATE, -1);
+            if(rate != -1) {
+                StreamRates.Rates rates = new StreamRates.Rates(rate);
+                streamRates.setRates(rates);
+            }
             CommonApiUtils.postSuccessEvent(listener);
             return true;
         }