Android tv-casting lib: Implementing a retry mechanism for commission…

…er service resolution using NsdManager

examples/tv-casting-app/android/App/app/src/main/java/com/chip/casting/app/CommissionerDiscoveryFragment.java

@@ -107,6 +107,18 @@ public void handle(MatterError matterError) {
           }
         };
 
+    Button discoverButton = getView().findViewById(R.id.discoverButton);
+    discoverButton.setOnClickListener(
+        new View.OnClickListener() {
+          @Override
+          public void onClick(View v) {
+            Log.d(TAG, "Discovering on button click");
+            tvCastingApp.discoverVideoPlayerCommissioners(
+                DISCOVERY_DURATION_SECS, successCallback, failureCallback);
+          }
+        });
+
+    Log.d(TAG, "Auto discovering");
     tvCastingApp.discoverVideoPlayerCommissioners(
         DISCOVERY_DURATION_SECS, successCallback, failureCallback);
   }

examples/tv-casting-app/android/App/app/src/main/jni/com/chip/casting/NsdDiscoveryListener.java

@@ -71,7 +71,8 @@ public void onServiceFound(NsdServiceInfo service) {
               preCommissionedVideoPlayers,
               successCallback,
               failureCallback,
-              nsdManagerResolverAvailState));
+              nsdManagerResolverAvailState,
+              1));
     } else {
       Log.d(TAG, "Ignoring discovered service: " + service.toString());
     }

examples/tv-casting-app/android/App/app/src/main/jni/com/chip/casting/NsdResolveListener.java

@@ -22,25 +22,32 @@
 import android.util.Log;
 import chip.platform.NsdManagerServiceResolver;
 import java.util.List;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
 
 public class NsdResolveListener implements NsdManager.ResolveListener {
 
   private static final String TAG = NsdResolveListener.class.getSimpleName();
 
+  private static final int MAX_RESOLUTION_ATTEMPTS = 5;
+  private static final int RESOLUTION_ATTEMPT_DELAY_SECS = 1;
+
   private final NsdManager nsdManager;
   private final List<Long> deviceTypeFilter;
   private final List<VideoPlayer> preCommissionedVideoPlayers;
   private final SuccessCallback<DiscoveredNodeData> successCallback;
   private final FailureCallback failureCallback;
   private final NsdManagerServiceResolver.NsdManagerResolverAvailState nsdManagerResolverAvailState;
+  private final int resolutionAttemptNumber;
 
   public NsdResolveListener(
       NsdManager nsdManager,
       List<Long> deviceTypeFilter,
       List<VideoPlayer> preCommissionedVideoPlayers,
       SuccessCallback<DiscoveredNodeData> successCallback,
       FailureCallback failureCallback,
-      NsdManagerServiceResolver.NsdManagerResolverAvailState nsdManagerResolverAvailState) {
+      NsdManagerServiceResolver.NsdManagerResolverAvailState nsdManagerResolverAvailState,
+      int resolutionAttemptNumber) {
     this.nsdManager = nsdManager;
     this.deviceTypeFilter = deviceTypeFilter;
     this.preCommissionedVideoPlayers = preCommissionedVideoPlayers;
@@ -52,6 +59,7 @@ public NsdResolveListener(
     this.successCallback = successCallback;
     this.failureCallback = failureCallback;
     this.nsdManagerResolverAvailState = nsdManagerResolverAvailState;
+    this.resolutionAttemptNumber = resolutionAttemptNumber;
   }
 
   @Override
@@ -77,15 +85,41 @@ public void onServiceResolved(NsdServiceInfo serviceInfo) {
   @Override
   public void onResolveFailed(NsdServiceInfo serviceInfo, int errorCode) {
     if (nsdManagerResolverAvailState != null) {
-      nsdManagerResolverAvailState.signalFree();
+      if (errorCode != NsdManager.FAILURE_ALREADY_ACTIVE
+          || resolutionAttemptNumber >= MAX_RESOLUTION_ATTEMPTS) {
+        nsdManagerResolverAvailState.signalFree();
+      }
     }
 
     switch (errorCode) {
       case NsdManager.FAILURE_ALREADY_ACTIVE:
         Log.e(TAG, "NsdResolveListener FAILURE_ALREADY_ACTIVE - Service: " + serviceInfo);
-        failureCallback.handle(
-            new MatterError(
-                3, "NsdResolveListener FAILURE_ALREADY_ACTIVE - Service: " + serviceInfo));
+        if (resolutionAttemptNumber < MAX_RESOLUTION_ATTEMPTS) {
+          Log.d(TAG, "NsdResolveListener Scheduling a retry to resolve service " + serviceInfo);
+          Executors.newSingleThreadScheduledExecutor()
+              .schedule(
+                  new Runnable() {
+                    @Override
+                    public void run() {
+                      nsdManager.resolveService(
+                          serviceInfo,
+                          new NsdResolveListener(
+                              nsdManager,
+                              deviceTypeFilter,
+                              preCommissionedVideoPlayers,
+                              successCallback,
+                              failureCallback,
+                              nsdManagerResolverAvailState,
+                              resolutionAttemptNumber + 1));
+                    }
+                  },
+                  RESOLUTION_ATTEMPT_DELAY_SECS,
+                  TimeUnit.SECONDS);
+        } else { // giving up
+          failureCallback.handle(
+              new MatterError(
+                  3, "NsdResolveListener FAILURE_ALREADY_ACTIVE - Service: " + serviceInfo));
+        }
         break;
       case NsdManager.FAILURE_INTERNAL_ERROR:
         Log.e(TAG, "NsdResolveListener FAILURE_INTERNAL_ERROR - Service: " + serviceInfo);

examples/tv-casting-app/android/App/app/src/main/res/layout/fragment_commissioner_discovery.xml

@@ -20,6 +20,12 @@
             android:layout_height="wrap_content"
             android:text="Skip to manual commissioning >>" />
 
+        <Button
+            android:id="@+id/discoverButton"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="Discover>" />
+
         <TextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"