Implement serverTimestampBehavior on android

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

@@ -75,6 +75,12 @@ Task<Void> settings(String appName, Map<String, Object> settings) {
           UniversalFirebaseFirestoreStatics.FIRESTORE_SSL + "_" + appName, (boolean) settings.get("ssl"));
       }
 
+      // settings.serverTimestampBehavior
+      if (settings.containsKey("serverTimestampBehavior")) {
+        UniversalFirebasePreferences.getSharedInstance().setStringValue(
+          UniversalFirebaseFirestoreStatics.FIRESTORE_SERVER_TIMESTAMP_BEHAVIOR + "_" + appName, (String) settings.get("serverTimestampBehavior"));
+      }
+
       return null;
     });
   }

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

@@ -22,4 +22,5 @@ public class UniversalFirebaseFirestoreStatics {
   public static String FIRESTORE_HOST = "firebase_firestore_host";
   public static String FIRESTORE_PERSISTENCE = "firebase_firestore_persistence";
   public static String FIRESTORE_SSL = "firebase_firestore_ssl";
+  public static String FIRESTORE_SERVER_TIMESTAMP_BEHAVIOR = "firebase_firestore_server_timestamp_behavior";
 }

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

@@ -66,6 +66,7 @@ public void collectionOnSnapshot(
 
     FirebaseFirestore firebaseFirestore = getFirestoreForApp(appName);
     ReactNativeFirebaseFirestoreQuery firestoreQuery = new ReactNativeFirebaseFirestoreQuery(
+      appName,
       getQueryForFirestore(firebaseFirestore, path, type),
       filters,
       orders,
@@ -128,6 +129,7 @@ public void collectionGet(
   ) {
     FirebaseFirestore firebaseFirestore = getFirestoreForApp(appName);
     ReactNativeFirebaseFirestoreQuery query = new ReactNativeFirebaseFirestoreQuery(
+      appName,
       getQueryForFirestore(firebaseFirestore, path, type),
       filters,
       orders,
@@ -160,7 +162,7 @@ public void collectionGet(
   }
 
   private void sendOnSnapshotEvent(String appName, int listenerId, QuerySnapshot querySnapshot, MetadataChanges metadataChanges) {
-    Tasks.call(getTransactionalExecutor(Integer.toString(listenerId)), () -> snapshotToWritableMap("onSnapshot", querySnapshot, metadataChanges)).addOnCompleteListener(task -> {
+    Tasks.call(getTransactionalExecutor(Integer.toString(listenerId)), () -> snapshotToWritableMap(appName, "onSnapshot", querySnapshot, metadataChanges)).addOnCompleteListener(task -> {
       if (task.isSuccessful()) {
         WritableMap body = Arguments.createMap();
         body.putMap("snapshot", task.getResult());

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

@@ -19,8 +19,11 @@
 
 
 import com.facebook.react.bridge.Promise;
+import com.google.firebase.firestore.DocumentSnapshot;
 import com.google.firebase.firestore.FirebaseFirestoreException;
 
+import io.invertase.firebase.common.UniversalFirebasePreferences;
+
 import static io.invertase.firebase.common.ReactNativeFirebaseModule.rejectPromiseWithCodeAndMessage;
 import static io.invertase.firebase.common.ReactNativeFirebaseModule.rejectPromiseWithExceptionMap;
 
@@ -39,4 +42,20 @@ static void rejectPromiseFirestoreException(Promise promise, Exception exception
       rejectPromiseWithExceptionMap(promise, exception);
     }
   }
+
+  static DocumentSnapshot.ServerTimestampBehavior getServerTimestampBehavior(String appName) {
+    UniversalFirebasePreferences preferences = UniversalFirebasePreferences.getSharedInstance();
+    String key = UniversalFirebaseFirestoreStatics.FIRESTORE_SERVER_TIMESTAMP_BEHAVIOR + "_" + appName;
+    String behavior = preferences.getStringValue(key, "none");
+
+    if ("estimate".equals(behavior)) {
+      return DocumentSnapshot.ServerTimestampBehavior.ESTIMATE;
+    }
+
+    if ("previous".equals(behavior)) {
+      return DocumentSnapshot.ServerTimestampBehavior.PREVIOUS;
+    }
+
+    return DocumentSnapshot.ServerTimestampBehavior.NONE;
+  }
 }

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

@@ -131,7 +131,7 @@ public void documentGet(String appName, String path, ReadableMap getOptions, Pro
 
     Tasks.call(getExecutor(), () -> {
       DocumentSnapshot documentSnapshot = Tasks.await(documentReference.get(source));
-      return snapshotToWritableMap(documentSnapshot);
+      return snapshotToWritableMap(appName, documentSnapshot);
     }).addOnCompleteListener(task -> {
       if (task.isSuccessful()) {
         promise.resolve(task.getResult());
@@ -261,7 +261,7 @@ public void documentBatch(String appName, ReadableArray writes, Promise promise)
   }
 
   private void sendOnSnapshotEvent(String appName, int listenerId, DocumentSnapshot documentSnapshot) {
-    Tasks.call(getExecutor(), () -> snapshotToWritableMap(documentSnapshot)).addOnCompleteListener(task -> {
+    Tasks.call(getExecutor(), () -> snapshotToWritableMap(appName, documentSnapshot)).addOnCompleteListener(task -> {
       if (task.isSuccessful()) {
         WritableMap body = Arguments.createMap();
         body.putMap("snapshot", task.getResult());

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

@@ -37,14 +37,17 @@
 import static io.invertase.firebase.firestore.ReactNativeFirebaseFirestoreSerialize.*;
 
 public class ReactNativeFirebaseFirestoreQuery {
+  String appName;
   Query query;
 
   ReactNativeFirebaseFirestoreQuery(
+    String appName,
     Query query,
     ReadableArray filters,
     ReadableArray orders,
     ReadableMap options
   ) {
+    this.appName = appName;
     this.query = query;
     applyFilters(filters);
     applyOrders(orders);
@@ -54,7 +57,7 @@ public class ReactNativeFirebaseFirestoreQuery {
   public Task<WritableMap> get(Executor executor, Source source) {
     return Tasks.call(executor, () -> {
       QuerySnapshot querySnapshot = Tasks.await(query.get(source));
-      return snapshotToWritableMap("get", querySnapshot, null);
+      return snapshotToWritableMap(this.appName, "get", querySnapshot, null);
     });
   }
 

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

@@ -48,6 +48,7 @@
 
 import javax.annotation.Nullable;
 
+import static io.invertase.firebase.firestore.ReactNativeFirebaseFirestoreCommon.getServerTimestampBehavior;
 import static io.invertase.firebase.common.RCTConvertFirebase.toHashMap;
 
 // public access for native re-use in brownfield apps
@@ -99,7 +100,7 @@ public class ReactNativeFirebaseFirestoreSerialize {
    * @param documentSnapshot DocumentSnapshot
    * @return WritableMap
    */
-  static WritableMap snapshotToWritableMap(DocumentSnapshot documentSnapshot) {
+  static WritableMap snapshotToWritableMap(String appName, DocumentSnapshot documentSnapshot) {
     WritableArray metadata = Arguments.createArray();
     WritableMap documentMap = Arguments.createMap();
     SnapshotMetadata snapshotMetadata = documentSnapshot.getMetadata();
@@ -112,9 +113,11 @@ static WritableMap snapshotToWritableMap(DocumentSnapshot documentSnapshot) {
     documentMap.putString(KEY_PATH, documentSnapshot.getReference().getPath());
     documentMap.putBoolean(KEY_EXISTS, documentSnapshot.exists());
 
+    DocumentSnapshot.ServerTimestampBehavior timestampBehavior = getServerTimestampBehavior(appName);
+
     if (documentSnapshot.exists()) {
-      if (documentSnapshot.getData() != null) {
-        documentMap.putMap(KEY_DATA, objectMapToWritable(documentSnapshot.getData()));
+      if (documentSnapshot.getData(timestampBehavior) != null) {
+        documentMap.putMap(KEY_DATA, objectMapToWritable(documentSnapshot.getData(timestampBehavior)));
       }
     }
 
@@ -127,7 +130,7 @@ static WritableMap snapshotToWritableMap(DocumentSnapshot documentSnapshot) {
    * @param querySnapshot QuerySnapshot
    * @return WritableMap
    */
-  static WritableMap snapshotToWritableMap(String source, QuerySnapshot querySnapshot, @Nullable MetadataChanges metadataChanges) {
+  static WritableMap snapshotToWritableMap(String appName, String source, QuerySnapshot querySnapshot, @Nullable MetadataChanges metadataChanges) {
     WritableMap writableMap = Arguments.createMap();
     writableMap.putString("source", source);
 
@@ -140,22 +143,22 @@ static WritableMap snapshotToWritableMap(String source, QuerySnapshot querySnaps
       // If not listening to metadata changes, send the data back to JS land with a flag
       // indicating the data does not include these changes
       writableMap.putBoolean("excludesMetadataChanges", true);
-      writableMap.putArray(KEY_CHANGES, documentChangesToWritableArray(documentChangesList, null));
+      writableMap.putArray(KEY_CHANGES, documentChangesToWritableArray(appName, documentChangesList, null));
     } else {
       // If listening to metadata changes, get the changes list with document changes array.
       // To indicate whether a document change was because of metadata change, we check whether
       // its in the raw list by document key.
       writableMap.putBoolean("excludesMetadataChanges", false);
       List<DocumentChange> documentMetadataChangesList = querySnapshot.getDocumentChanges(MetadataChanges.INCLUDE);
-      writableMap.putArray(KEY_CHANGES, documentChangesToWritableArray(documentMetadataChangesList, documentChangesList));
+      writableMap.putArray(KEY_CHANGES, documentChangesToWritableArray(appName, documentMetadataChangesList, documentChangesList));
     }
 
     SnapshotMetadata snapshotMetadata = querySnapshot.getMetadata();
     List<DocumentSnapshot> documentSnapshots = querySnapshot.getDocuments();
 
     // set documents
     for (DocumentSnapshot documentSnapshot : documentSnapshots) {
-      documents.pushMap(snapshotToWritableMap(documentSnapshot));
+      documents.pushMap(snapshotToWritableMap(appName, documentSnapshot));
     }
     writableMap.putArray(KEY_DOCUMENTS, documents);
 
@@ -174,7 +177,7 @@ static WritableMap snapshotToWritableMap(String source, QuerySnapshot querySnaps
    * @param documentChanges List<DocumentChange>
    * @return WritableArray
    */
-  private static WritableArray documentChangesToWritableArray(List<DocumentChange> documentChanges, @Nullable List<DocumentChange> comparableDocumentChanges) {
+  private static WritableArray documentChangesToWritableArray(String appName, List<DocumentChange> documentChanges, @Nullable List<DocumentChange> comparableDocumentChanges) {
     WritableArray documentChangesWritable = Arguments.createArray();
 
     boolean checkIfMetadataChange = comparableDocumentChanges != null;
@@ -191,7 +194,7 @@ private static WritableArray documentChangesToWritableArray(List<DocumentChange>
         }
       }
 
-      documentChangesWritable.pushMap(documentChangeToWritableMap(documentChange, isMetadataChange));
+      documentChangesWritable.pushMap(documentChangeToWritableMap(appName, documentChange, isMetadataChange));
     }
 
     return documentChangesWritable;
@@ -203,7 +206,7 @@ private static WritableArray documentChangesToWritableArray(List<DocumentChange>
    * @param documentChange DocumentChange
    * @return WritableMap
    */
-  private static WritableMap documentChangeToWritableMap(DocumentChange documentChange, boolean isMetadataChange) {
+  private static WritableMap documentChangeToWritableMap(String appName, DocumentChange documentChange, boolean isMetadataChange) {
     WritableMap documentChangeMap = Arguments.createMap();
     documentChangeMap.putBoolean("isMetadataChange", isMetadataChange);
 
@@ -221,7 +224,7 @@ private static WritableMap documentChangeToWritableMap(DocumentChange documentCh
 
     documentChangeMap.putMap(
       KEY_DOC_CHANGE_DOCUMENT,
-      snapshotToWritableMap(documentChange.getDocument())
+      snapshotToWritableMap(appName, documentChange.getDocument())
     );
 
     documentChangeMap.putInt(KEY_DOC_CHANGE_NEW_INDEX, documentChange.getNewIndex());

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

@@ -72,7 +72,7 @@ public void transactionGetDocument(String appName, int transactionId, String pat
     DocumentReference documentReference = getDocumentForFirestore(firebaseFirestore, path);
 
     Tasks
-      .call(getTransactionalExecutor(), () -> snapshotToWritableMap(transactionHandler.getDocument(documentReference)))
+      .call(getTransactionalExecutor(), () -> snapshotToWritableMap(appName, transactionHandler.getDocument(documentReference)))
       .addOnCompleteListener(task -> {
         if (task.isSuccessful()) {
           promise.resolve(task.getResult());

packages/firestore/lib/index.d.ts

@@ -1426,6 +1426,20 @@ export namespace FirebaseFirestoreTypes {
      * If set to false or omitted, the SDK throws an exception when it encounters properties of type undefined.
      */
     ignoreUndefinedProperties?: boolean;
+
+    /**
+     * 
+     * If set, controls the return value for server timestamps that have not yet been set to their final value.
+     * 
+     * By specifying 'estimate', pending server timestamps return an estimate based on the local clock. 
+     * This estimate will differ from the final value and cause these values to change once the server result becomes available.
+     * 
+     * By specifying 'previous', pending timestamps will be ignored and return their previous value instead.
+     * 
+     * If omitted or set to 'none', null will be returned by default until the server value becomes available.
+     * 
+     */
+    serverTimestampBehavior?: 'estimate' | 'previous' | 'none';
   }
 
   /**

packages/firestore/lib/index.js

@@ -270,6 +270,14 @@ class FirebaseFirestoreModule extends FirebaseModule {
       throw new Error("firebase.firestore().settings(*) 'settings.ssl' must be a boolean value.");
     }
 
+    if (!['estimate', 'previous', 'none'].includes(settings.serverTimestampBehavior)) {
+      return Promise.reject(
+        new Error(
+          "firebase.firestore().settings(*) 'settings.serverTimestampBehavior' must be one of 'estimate', 'previous', 'none'.",
+        )
+      );
+    }
+
     if (!isUndefined(settings.ignoreUndefinedProperties)) {
       if (!isBoolean(settings.ignoreUndefinedProperties)) {
         return Promise.reject(