feat(firestore): add support for onSnapshotsInSync

packages/firestore/android/src/main/java/io/invertase/firebase/firestore/UniversalFirebaseFirestoreModule.java

@@ -22,10 +22,15 @@
 import static io.invertase.firebase.firestore.UniversalFirebaseFirestoreCommon.instanceCache;
 
 import android.content.Context;
+import android.util.SparseArray;
+import com.facebook.react.bridge.Arguments;
+import com.facebook.react.bridge.WritableMap;
 import com.google.android.gms.tasks.Task;
 import com.google.android.gms.tasks.Tasks;
 import com.google.firebase.firestore.FirebaseFirestore;
+import com.google.firebase.firestore.ListenerRegistration;
 import com.google.firebase.firestore.LoadBundleTask;
+import io.invertase.firebase.common.ReactNativeFirebaseEventEmitter;
 import io.invertase.firebase.common.UniversalFirebaseModule;
 import io.invertase.firebase.common.UniversalFirebasePreferences;
 import java.nio.charset.StandardCharsets;
@@ -34,13 +39,43 @@
 import java.util.Objects;
 
 public class UniversalFirebaseFirestoreModule extends UniversalFirebaseModule {
+  private static SparseArray<ListenerRegistration> onSnapshotInSyncListeners = new SparseArray<>();
 
   private static HashMap<String, String> emulatorConfigs = new HashMap<>();
 
   UniversalFirebaseFirestoreModule(Context context, String serviceName) {
     super(context, serviceName);
   }
 
+  void addSnapshotsInSync(String appName, String databaseId, int listenerId) {
+
+    FirebaseFirestore firebaseFirestore = getFirestoreForApp(appName, databaseId);
+    ListenerRegistration listenerRegistration =
+        firebaseFirestore.addSnapshotsInSyncListener(
+            () -> {
+              ReactNativeFirebaseEventEmitter emitter =
+                  ReactNativeFirebaseEventEmitter.getSharedInstance();
+              WritableMap body = Arguments.createMap();
+              emitter.sendEvent(
+                  new ReactNativeFirebaseFirestoreEvent(
+                      ReactNativeFirebaseFirestoreEvent.SNAPSHOT_IN_SYNC_EVENT_SYNC,
+                      body,
+                      appName,
+                      databaseId,
+                      listenerId));
+            });
+
+    onSnapshotInSyncListeners.put(listenerId, listenerRegistration);
+  }
+
+  void removeSnapshotsInSync(String appName, String databaseId, int listenerId) {
+    ListenerRegistration listenerRegistration = onSnapshotInSyncListeners.get(listenerId);
+    if (listenerRegistration != null) {
+      listenerRegistration.remove();
+      onSnapshotInSyncListeners.remove(listenerId);
+    }
+  }
+
   Task<Void> disableNetwork(String appName, String databaseId) {
     return getFirestoreForApp(appName, databaseId).disableNetwork();
   }

packages/firestore/android/src/reactnative/java/io/invertase/firebase/firestore/ReactNativeFirebaseFirestoreEvent.java

@@ -26,6 +26,7 @@ public class ReactNativeFirebaseFirestoreEvent implements NativeEvent {
   static final String COLLECTION_EVENT_SYNC = "firestore_collection_sync_event";
   static final String DOCUMENT_EVENT_SYNC = "firestore_document_sync_event";
   static final String TRANSACTION_EVENT_SYNC = "firestore_transaction_event";
+  static final String SNAPSHOT_IN_SYNC_EVENT_SYNC = "firestore_snapshots_in_sync_event";
   private static final String KEY_ID = "listenerId";
   private static final String KEY_BODY = "body";
   private static final String KEY_APP_NAME = "appName";

packages/firestore/android/src/reactnative/java/io/invertase/firebase/firestore/ReactNativeFirebaseFirestoreModule.java

@@ -193,6 +193,20 @@ public void persistenceCacheIndexManager(
     promise.resolve(null);
   }
 
+  @ReactMethod
+  public void addSnapshotsInSync(
+      String appName, String databaseId, int listenerId, Promise promise) {
+    module.addSnapshotsInSync(appName, databaseId, listenerId);
+    promise.resolve(null);
+  }
+
+  @ReactMethod
+  public void removeSnapshotsInSync(
+      String appName, String databaseId, int listenerId, Promise promise) {
+    module.removeSnapshotsInSync(appName, databaseId, listenerId);
+    promise.resolve(null);
+  }
+
   private WritableMap taskProgressToWritableMap(LoadBundleTaskProgress progress) {
     WritableMap writableMap = Arguments.createMap();
     writableMap.putDouble("bytesLoaded", progress.getBytesLoaded());

packages/firestore/e2e/firestore.e2e.js

@@ -915,5 +915,101 @@ describe('firestore()', function () {
         });
       });
     });
+
+    describe('snapshotsInSync', function () {
+      const { getFirestore, onSnapshotsInSync, doc, setDoc, deleteDoc } = firestoreModular;
+
+      it('snapshotsInSync fires when document is updated and synced', async function () {
+        const events = [];
+
+        const db = getFirestore();
+        const testDoc1 = doc(db, `${COLLECTION}/snapshotsInSync1`);
+        const testDoc2 = doc(db, `${COLLECTION}/snapshotsInSync2`);
+
+        if (Platform.other) {
+          // Should throw error for lite SDK
+          try {
+            const unsubscribe = onSnapshotsInSync(getFirestore(), () => {});
+            unsubscribe();
+          } catch (e) {
+            e.message.should.equal('Not supported in the lite SDK.');
+          }
+          return;
+        }
+
+        let unsubscribe;
+        const syncPromise = new Promise(resolve => {
+          unsubscribe = onSnapshotsInSync(db, () => {
+            events.push('sync');
+            if (events.length >= 1) {
+              resolve();
+            }
+          });
+        });
+
+        await Promise.all([setDoc(testDoc1, { test: 1 }), setDoc(testDoc2, { test: 2 })]);
+
+        await syncPromise;
+
+        unsubscribe();
+
+        // Verify unsubscribe worked by doing another write
+        await setDoc(testDoc1, { test: 3 });
+
+        // Cleanup
+        await Promise.all([deleteDoc(testDoc1), deleteDoc(testDoc2)]);
+
+        events.length.should.be.greaterThan(0);
+        events.forEach(event => event.should.equal('sync'));
+      });
+
+      it('unsubscribe() call should prevent further sync events', async function () {
+        const events = [];
+
+        const db = getFirestore();
+        const testDoc1 = doc(db, `${COLLECTION}/snapshotsInSync1`);
+        const testDoc2 = doc(db, `${COLLECTION}/snapshotsInSync2`);
+
+        if (Platform.other) {
+          // Should throw error for lite SDK
+          try {
+            const unsubscribe = onSnapshotsInSync(getFirestore(), () => {});
+            unsubscribe();
+          } catch (e) {
+            e.message.should.equal('Not supported in the lite SDK.');
+          }
+          return;
+        }
+
+        let unsubscribe;
+        const syncPromise = new Promise(resolve => {
+          unsubscribe = onSnapshotsInSync(db, () => {
+            events.push('sync');
+            if (events.length >= 1) {
+              resolve();
+            }
+          });
+        });
+
+        // Trigger initial sync events
+        await Promise.all([setDoc(testDoc1, { test: 1 }), setDoc(testDoc2, { test: 2 })]);
+
+        await syncPromise;
+
+        // Record the number of events before unsubscribe
+        const eventsBeforeUnsubscribe = events.length;
+
+        await unsubscribe();
+
+        await setDoc(testDoc1, { test: 3 });
+        await setDoc(testDoc2, { test: 4 });
+
+        await Promise.all([deleteDoc(testDoc1), deleteDoc(testDoc2)]);
+
+        // Verify that no additional events were recorded after unsubscribe
+        events.length.should.equal(eventsBeforeUnsubscribe);
+        events.forEach(event => event.should.equal('sync'));
+      });
+    });
   });
 });

packages/firestore/ios/RNFBFirestore/RNFBFirestoreModule.m

@@ -16,12 +16,15 @@
  */
 
 #import "RNFBFirestoreModule.h"
+#import <RNFBApp/RNFBRCTEventEmitter.h>
 #import <React/RCTUtils.h>
 #import "FirebaseFirestoreInternal/FIRPersistentCacheIndexManager.h"
 #import "RNFBFirestoreCommon.h"
 #import "RNFBPreferences.h"
 
 NSMutableDictionary *emulatorConfigs;
+static __strong NSMutableDictionary *snapshotsInSyncListeners;
+static NSString *const RNFB_FIRESTORE_SNAPSHOTS_IN_SYNC = @"firestore_snapshots_in_sync_event";
 
 @implementation RNFBFirestoreModule
 #pragma mark -
@@ -240,6 +243,51 @@ + (BOOL)requiresMainQueueSetup {
   resolve(nil);
 }
 
+RCT_EXPORT_METHOD(addSnapshotsInSync
+                  : (FIRApp *)firebaseApp
+                  : (NSString *)databaseId
+                  : (nonnull NSNumber *)listenerId
+                  : (RCTPromiseResolveBlock)resolve
+                  : (RCTPromiseRejectBlock)reject) {
+  if (snapshotsInSyncListeners[listenerId]) {
+    resolve(nil);
+    return;
+  }
+
+  FIRFirestore *firestore = [RNFBFirestoreCommon getFirestoreForApp:firebaseApp
+                                                         databaseId:databaseId];
+
+  id<FIRListenerRegistration> listener = [firestore addSnapshotsInSyncListener:^{
+    [[RNFBRCTEventEmitter shared]
+        sendEventWithName:RNFB_FIRESTORE_SNAPSHOTS_IN_SYNC
+                     body:@{
+                       @"appName" : [RNFBSharedUtils getAppJavaScriptName:firebaseApp.name],
+                       @"databaseId" : databaseId,
+                       @"listenerId" : listenerId,
+                       @"body" : @{}
+                     }];
+  }];
+
+  snapshotsInSyncListeners[listenerId] = listener;
+
+  resolve(nil);
+}
+
+RCT_EXPORT_METHOD(removeSnapshotsInSync
+                  : (FIRApp *)firebaseApp
+                  : (NSString *)databaseId
+                  : (nonnull NSNumber *)listenerId
+                  : (RCTPromiseResolveBlock)resolve
+                  : (RCTPromiseRejectBlock)reject) {
+  id<FIRListenerRegistration> listener = snapshotsInSyncListeners[listenerId];
+  if (listener) {
+    [listener remove];
+    [snapshotsInSyncListeners removeObjectForKey:listenerId];
+  }
+
+  resolve(nil);
+}
+
 - (NSMutableDictionary *)taskProgressToDictionary:(FIRLoadBundleTaskProgress *)progress {
   NSMutableDictionary *progressMap = [[NSMutableDictionary alloc] init];
   progressMap[@"bytesLoaded"] = @(progress.bytesLoaded);

packages/firestore/lib/index.js

@@ -56,6 +56,7 @@ const nativeEvents = [
   'firestore_collection_sync_event',
   'firestore_document_sync_event',
   'firestore_transaction_event',
+  'firestore_snapshots_in_sync_event',
 ];
 
 class FirebaseFirestoreModule extends FirebaseModule {
@@ -84,6 +85,13 @@ class FirebaseFirestoreModule extends FirebaseModule {
       );
     });
 
+    this.emitter.addListener(this.eventNameForApp('firestore_snapshots_in_sync_event'), event => {
+      this.emitter.emit(
+        this.eventNameForApp(`firestore_snapshots_in_sync_event:${event.listenerId}`),
+        event,
+      );
+    });
+
     this._settings = {
       ignoreUndefinedProperties: false,
       persistence: true,

packages/firestore/lib/modular/index.js

@@ -89,6 +89,24 @@
   return firestore.collectionGroup.call(firestore, collectionId, MODULAR_DEPRECATION_ARG);
 }
 
+let _id_SnapshotInSync = 0;
+
+export function onSnapshotsInSync(firestore, callback) {
+  const listenerId = _id_SnapshotInSync++;
+  firestore.native.addSnapshotsInSync(listenerId);
+  const onSnapshotsInSyncSubscription = firestore.emitter.addListener(
+    firestore.eventNameForApp(`firestore_snapshots_in_sync_event:${listenerId}`),
+    () => {
+      callback();
+    },
+  );
+
+  return () => {
+    onSnapshotsInSyncSubscription.remove();
+    firestore.native.removeSnapshotsInSync(listenerId);
+  };
+}
+
 /**
  * @param {DocumentReference} reference
  * @param {import('.').PartialWithFieldValue} data

packages/firestore/lib/web/RNFBFirestoreModule.js

@@ -132,6 +132,14 @@ export default {
     return rejectWithCodeAndMessage('unsupported', 'Not supported in the lite SDK.');
   },
 
+  addSnapshotsInSync() {
+    return rejectWithCodeAndMessage('unsupported', 'Not supported in the lite SDK.');
+  },
+
+  removeSnapshotsInSync() {
+    return rejectWithCodeAndMessage('unsupported', 'Not supported in the lite SDK.');
+  },
+
   /**
    * Use the Firestore emulator.
    * @param {string} appName - The app name.

tests/test-app/examples/firestore/onSnapshotInSync.js

@@ -0,0 +1,48 @@
+import React, { useEffect } from 'react';
+import { AppRegistry, Button, Text, View } from 'react-native';
+
+import '@react-native-firebase/app';
+import firestore, { onSnapshotsInSync } from '@react-native-firebase/firestore';
+
+const fire = firestore();
+function App() {
+  let unsubscribe;
+  useEffect(() => {
+    unsubscribe = onSnapshotsInSync(fire, () => {
+      console.log('onSnapshotsInSync');
+    });
+  }, []);
+
+  async function addDocument() {
+    await firestore().collection('flutter-tests').doc('one').set({ foo: 'bar' });
+  }
+
+  return (
+    <View>
+      <Text>React Native Firebase</Text>
+      <Text>onSnapshotsInSync API</Text>
+      <Button
+        title="add document"
+        onPress={async () => {
+          try {
+            addDocument();
+          } catch (e) {
+            console.log('EEEE', e);
+          }
+        }}
+      />
+      <Button
+        title="unsubscribe to snapshot in sync"
+        onPress={async () => {
+          try {
+            unsubscribe();
+          } catch (e) {
+            console.log('EEEE', e);
+          }
+        }}
+      />
+    </View>
+  );
+}
+
+AppRegistry.registerComponent('testing', () => App);