fix(messaging, android): prevent OOM by limiting stored notifications

Author: sean5940

packages/messaging/android/src/main/java/io/invertase/firebase/messaging/ReactNativeFirebaseMessagingStoreImpl.java

@@ -5,6 +5,9 @@
 import static io.invertase.firebase.messaging.ReactNativeFirebaseMessagingSerializer.remoteMessageFromReadableMap;
 import static io.invertase.firebase.messaging.ReactNativeFirebaseMessagingSerializer.remoteMessageToWritableMap;
 
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
 import com.facebook.react.bridge.ReadableMap;
 import com.facebook.react.bridge.WritableMap;
 import com.google.firebase.messaging.RemoteMessage;
@@ -17,9 +20,54 @@
 
 public class ReactNativeFirebaseMessagingStoreImpl implements ReactNativeFirebaseMessagingStore {
 
+  private static final String KEY_MAX_STORED_NOTIFICATIONS = "rn_firebase_messaging_max_stored_notifications";
   private static final String S_KEY_ALL_NOTIFICATION_IDS = "all_notification_ids";
-  private static final int MAX_SIZE_NOTIFICATIONS = 100;
   private final String DELIMITER = ",";
+  private static final int DEFAULT_MAX_SIZE_NOTIFICATIONS = 100;
+  private static int MAX_SIZE_NOTIFICATIONS = DEFAULT_MAX_SIZE_NOTIFICATIONS;
+  private static boolean isInitialized = false;
+
+  private int getMaxNotificationSize() {
+    if (isInitialized) return MAX_SIZE_NOTIFICATIONS;
+
+    int maxSize = DEFAULT_MAX_SIZE_NOTIFICATIONS;
+    ReactNativeFirebaseJSON json = ReactNativeFirebaseJSON.getSharedInstance();
+    ReactNativeFirebaseMeta meta = ReactNativeFirebaseMeta.getSharedInstance();
+    ReactNativeFirebasePreferences prefs = ReactNativeFirebasePreferences.getSharedInstance();
+
+    try {
+      // Priority: SharedPreferences -> firebase.json -> AndroidManifest
+      // Note: ReactNativeFirebaseMeta doesn't have getIntValue, so we check meta.contains
+      // and read from AndroidManifest directly if needed
+      if (prefs.contains(KEY_MAX_STORED_NOTIFICATIONS)) {
+        maxSize = prefs.getIntValue(KEY_MAX_STORED_NOTIFICATIONS, DEFAULT_MAX_SIZE_NOTIFICATIONS);
+      } else if (json.contains(KEY_MAX_STORED_NOTIFICATIONS)) {
+        maxSize = json.getIntValue(KEY_MAX_STORED_NOTIFICATIONS, DEFAULT_MAX_SIZE_NOTIFICATIONS);
+      } else if (meta.contains(KEY_MAX_STORED_NOTIFICATIONS)) {
+        // ReactNativeFirebaseMeta uses rnfirebase_ prefix, but we want to read the raw key
+        // So we read directly from AndroidManifest using the key as-is
+        try {
+          Context context = io.invertase.firebase.app.ReactNativeFirebaseApp.getApplicationContext();
+          ApplicationInfo appInfo = context.getPackageManager()
+              .getApplicationInfo(context.getPackageName(), PackageManager.GET_META_DATA);
+          if (appInfo != null && appInfo.metaData != null) {
+            maxSize = appInfo.metaData.getInt(KEY_MAX_STORED_NOTIFICATIONS, DEFAULT_MAX_SIZE_NOTIFICATIONS);
+          }
+        } catch (Exception e) {
+          // Ignore and use default
+        }
+      }
+
+      // Safety cap: prevent values > 100 to avoid re-introducing OOM risk
+      MAX_SIZE_NOTIFICATIONS = Math.min(maxSize, DEFAULT_MAX_SIZE_NOTIFICATIONS);
+    } catch (Exception e) {
+      // Ignore and use default
+      MAX_SIZE_NOTIFICATIONS = DEFAULT_MAX_SIZE_NOTIFICATIONS;
+    }
+
+    isInitialized = true;
+    return MAX_SIZE_NOTIFICATIONS;
+  }
 
   @Override
   public void storeFirebaseMessage(RemoteMessage remoteMessage) {
@@ -32,7 +80,7 @@ public void storeFirebaseMessage(RemoteMessage remoteMessage) {
       // remove old notifications message before store to free space as needed
       String notificationIds = preferences.getStringValue(S_KEY_ALL_NOTIFICATION_IDS, "");
       List<String> allNotificationList = convertToArray(notificationIds);
-      while (allNotificationList.size() > MAX_SIZE_NOTIFICATIONS - 1) {
+      while (allNotificationList.size() > getMaxNotificationSize() - 1) {
         clearFirebaseMessage(allNotificationList.get(0));
         allNotificationList.remove(0);
       }