fix(network): fresh getStatus on iOS; callback-driven, deduplicated events on Android

network/android/src/main/java/com/capacitorjs/plugins/network/Network.java

@@ -5,6 +5,7 @@
 import android.net.ConnectivityManager;
 import android.net.ConnectivityManager.NetworkCallback;
 import android.net.NetworkCapabilities;
+import android.os.Build;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
@@ -14,28 +15,57 @@ public class Network {
      * Interface for callbacks when network status changes.
      */
     interface NetworkStatusChangeListener {
-        void onNetworkStatusChanged(boolean wasLostEvent);
+        void onNetworkStatusChanged(NetworkStatus status);
     }
 
+    // Status is derived from the callback arguments. Querying ConnectivityManager from inside a
+    // NetworkCallback can return state that is already out of sync with the callback.
     class ConnectivityCallback extends NetworkCallback {
 
+        @Nullable
+        private android.net.Network currentNetwork;
+
+        @Override
+        public void onAvailable(@NonNull android.net.Network network) {
+            super.onAvailable(network);
+            currentNetwork = network;
+            // From API 26 onCapabilitiesChanged always follows onAvailable for the default network.
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) {
+                notifyStatus(statusFromCapabilities(connectivityManager.getNetworkCapabilities(network)));
+            }
+        }
+
         @Override
         public void onLost(@NonNull android.net.Network network) {
             super.onLost(network);
-            statusChangeListener.onNetworkStatusChanged(true);
+            // A late onLost for the previous default network must not override the new one.
+            if (currentNetwork != null && !currentNetwork.equals(network)) {
+                return;
+            }
+            currentNetwork = null;
+            notifyStatus(new NetworkStatus());
         }
 
         @Override
         public void onCapabilitiesChanged(@NonNull android.net.Network network, @NonNull NetworkCapabilities networkCapabilities) {
             super.onCapabilitiesChanged(network, networkCapabilities);
-            statusChangeListener.onNetworkStatusChanged(false);
+            currentNetwork = network;
+            notifyStatus(statusFromCapabilities(networkCapabilities));
+        }
+
+        private void notifyStatus(NetworkStatus status) {
+            NetworkStatusChangeListener listener = statusChangeListener;
+            if (listener != null) {
+                listener.onNetworkStatusChanged(status);
+            }
         }
     }
 
     @Nullable
-    private NetworkStatusChangeListener statusChangeListener;
+    private volatile NetworkStatusChangeListener statusChangeListener;
 
     private ConnectivityCallback connectivityCallback;
+    private boolean monitoring = false;
     private Context context;
     private ConnectivityManager connectivityManager;
     private BroadcastReceiver receiver;
@@ -77,16 +107,24 @@ public NetworkStatus getNetworkStatus() {
             android.net.Network activeNetwork = this.connectivityManager.getActiveNetwork();
             NetworkCapabilities capabilities = this.connectivityManager.getNetworkCapabilities(this.connectivityManager.getActiveNetwork());
             if (activeNetwork != null && capabilities != null) {
-                networkStatus.connected =
-                    capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED) &&
-                    capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
-                if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
-                    networkStatus.connectionType = NetworkStatus.ConnectionType.WIFI;
-                } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
-                    networkStatus.connectionType = NetworkStatus.ConnectionType.CELLULAR;
-                } else {
-                    networkStatus.connectionType = NetworkStatus.ConnectionType.UNKNOWN;
-                }
+                networkStatus = statusFromCapabilities(capabilities);
+            }
+        }
+        return networkStatus;
+    }
+
+    static NetworkStatus statusFromCapabilities(@Nullable NetworkCapabilities capabilities) {
+        NetworkStatus networkStatus = new NetworkStatus();
+        if (capabilities != null) {
+            networkStatus.connected =
+                capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED) &&
+                capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
+            if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
+                networkStatus.connectionType = NetworkStatus.ConnectionType.WIFI;
+            } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
+                networkStatus.connectionType = NetworkStatus.ConnectionType.CELLULAR;
+            } else {
+                networkStatus.connectionType = NetworkStatus.ConnectionType.UNKNOWN;
             }
         }
         return networkStatus;
@@ -109,16 +147,24 @@ private NetworkStatus getAndParseNetworkInfo() {
     }
 
     /**
-     * Register a network callback.
+     * Register a network callback. Does nothing if it is already registered.
      */
-    public void startMonitoring() {
+    public synchronized void startMonitoring() {
+        if (monitoring) {
+            return;
+        }
         connectivityManager.registerDefaultNetworkCallback(connectivityCallback);
+        monitoring = true;
     }
 
     /**
-     * Unregister the network callback.
+     * Unregister the network callback. Does nothing if it is not registered.
      */
-    public void stopMonitoring() {
+    public synchronized void stopMonitoring() {
+        if (!monitoring) {
+            return;
+        }
+        monitoring = false;
         connectivityManager.unregisterNetworkCallback(connectivityCallback);
     }
 }

network/android/src/main/java/com/capacitorjs/plugins/network/NetworkPlugin.java

@@ -1,7 +1,7 @@
 package com.capacitorjs.plugins.network;
 
-import android.os.Build;
 import android.util.Log;
+import androidx.annotation.Nullable;
 import com.getcapacitor.JSObject;
 import com.getcapacitor.Plugin;
 import com.getcapacitor.PluginCall;
@@ -13,25 +13,18 @@ public class NetworkPlugin extends Plugin {
 
     private Network implementation;
     public static final String NETWORK_CHANGE_EVENT = "networkStatusChange";
-    private NetworkStatus prePauseNetworkStatus = null;
+
+    @Nullable
+    private NetworkStatus lastNotifiedStatus = null;
 
     /**
      * Monitor for network status changes and fire our event.
      */
     @Override
     public void load() {
         implementation = new Network(getContext());
-        Network.NetworkStatusChangeListener listener = (wasLostEvent) -> {
-            if (wasLostEvent) {
-                JSObject jsObject = new JSObject();
-                jsObject.put("connected", false);
-                jsObject.put("connectionType", "none");
-                notifyListeners(NETWORK_CHANGE_EVENT, jsObject);
-            } else {
-                updateNetworkStatus();
-            }
-        };
-        implementation.setStatusChangeListener(listener);
+        implementation.setStatusChangeListener(this::notifyIfChanged);
+        implementation.startMonitoring();
     }
 
     /**
@@ -40,6 +33,7 @@ public void load() {
     @Override
     protected void handleOnDestroy() {
         implementation.setStatusChangeListener(null);
+        implementation.stopMonitoring();
     }
 
     /**
@@ -52,37 +46,38 @@ public void getStatus(PluginCall call) {
     }
 
     /**
-     * Register the IntentReceiver on resume
+     * Register the network callback on resume
      */
     @Override
     protected void handleOnResume() {
         implementation.startMonitoring();
+        // Registering delivers the current default network, but nothing is delivered when there is
+        // none, so a connection lost while paused has to be reported from here.
         NetworkStatus afterPauseNetworkStatus = implementation.getNetworkStatus();
-        if (
-            prePauseNetworkStatus != null &&
-            !afterPauseNetworkStatus.connected &&
-            (prePauseNetworkStatus.connected || afterPauseNetworkStatus.connectionType != prePauseNetworkStatus.connectionType)
-        ) {
-            Log.d(
-                "Capacitor/NetworkPlugin",
-                "Detected pre-pause and after-pause network status mismatch. Updating network status and notifying listeners."
-            );
-            this.updateNetworkStatus();
+        if (!afterPauseNetworkStatus.connected && hasNotified()) {
+            Log.d("Capacitor/NetworkPlugin", "Network status is not connected after resume. Notifying listeners if it changed.");
+            notifyIfChanged(afterPauseNetworkStatus);
         }
-        this.prePauseNetworkStatus = null;
     }
 
     /**
-     * Unregister the IntentReceiver on pause to avoid leaking it
+     * Unregister the network callback on pause to avoid leaking it
      */
     @Override
     protected void handleOnPause() {
-        this.prePauseNetworkStatus = implementation.getNetworkStatus();
         implementation.stopMonitoring();
     }
 
-    private void updateNetworkStatus() {
-        notifyListeners(NETWORK_CHANGE_EVENT, parseNetworkStatus(implementation.getNetworkStatus()));
+    private synchronized boolean hasNotified() {
+        return lastNotifiedStatus != null;
+    }
+
+    private synchronized void notifyIfChanged(NetworkStatus status) {
+        if (status.equals(lastNotifiedStatus)) {
+            return;
+        }
+        lastNotifiedStatus = status;
+        notifyListeners(NETWORK_CHANGE_EVENT, parseNetworkStatus(status));
     }
 
     private JSObject parseNetworkStatus(NetworkStatus networkStatus) {

network/android/src/main/java/com/capacitorjs/plugins/network/NetworkStatus.java

@@ -1,5 +1,7 @@
 package com.capacitorjs.plugins.network;
 
+import java.util.Objects;
+
 public class NetworkStatus {
 
     public enum ConnectionType {
@@ -21,4 +23,21 @@ public String getConnectionType() {
 
     public boolean connected = false;
     public ConnectionType connectionType = ConnectionType.NONE;
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof NetworkStatus)) {
+            return false;
+        }
+        NetworkStatus other = (NetworkStatus) o;
+        return connected == other.connected && connectionType == other.connectionType;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(connected, connectionType);
+    }
 }

network/ios/Sources/NetworkPlugin/Network.swift

@@ -29,7 +29,7 @@ public class Network {
     }
 
     func currentStatus() -> Network.Connection {
-        return reachability?.connection.equivalentEnum ?? Connection.unavailable
+        return reachability?.currentConnection.equivalentEnum ?? Connection.unavailable
     }
 }
 

network/ios/Sources/NetworkPlugin/Reachability.swift

@@ -92,11 +92,16 @@ public class Reachability {
         return connection
     }
 
-    public var connection: Connection {
-        if flags == nil {
-            try? setReachabilityFlags()
+    public var currentConnection: Connection {
+        var freshFlags = SCNetworkReachabilityFlags()
+        if SCNetworkReachabilityGetFlags(reachabilityRef, &freshFlags) {
+            reachabilitySerialQueue.sync { flags = freshFlags }
         }
+        return connection
+    }
 
+    public var connection: Connection {
+        if flags == nil { try? setReachabilityFlags() }
         switch flags?.connection {
         case .unavailable?, nil: return .unavailable
         case .cellular?: return allowsCellularConnection ? .cellular : .unavailable