fix(emulator): protect against double useEmulator calls natively

packages/auth/android/src/main/java/io/invertase/firebase/auth/ReactNativeFirebaseAuthModule.java

@@ -75,6 +75,7 @@ class ReactNativeFirebaseAuthModule extends ReactNativeFirebaseModule {
   private static final String TAG = "Auth";
   private static HashMap<String, FirebaseAuth.AuthStateListener> mAuthListeners = new HashMap<>();
   private static HashMap<String, FirebaseAuth.IdTokenListener> mIdTokenListeners = new HashMap<>();
+  private static HashMap<String, String> emulatorConfigs = new HashMap<>();
   private String mVerificationId;
   private String mLastPhoneNumber;
   private PhoneAuthProvider.ForceResendingToken mForceResendingToken;
@@ -1561,10 +1562,13 @@ public void verifyPasswordResetCode(String appName, String code, final Promise p
 
   @ReactMethod
   public void useEmulator(String appName, String host, int port) {
-    Log.d(TAG, "useEmulator");
-    FirebaseApp firebaseApp = FirebaseApp.getInstance(appName);
-    FirebaseAuth firebaseAuth = FirebaseAuth.getInstance(firebaseApp);
-    firebaseAuth.useEmulator(host, port);
+
+    if (emulatorConfigs.get(appName) == null) {
+      emulatorConfigs.put(appName, "true");
+      FirebaseApp firebaseApp = FirebaseApp.getInstance(appName);
+      FirebaseAuth firebaseAuth = FirebaseAuth.getInstance(firebaseApp);
+      firebaseAuth.useEmulator(host, port);
+    }
   }
 
   /* ------------------

packages/auth/ios/RNFBAuth/RNFBAuthModule.m

@@ -50,6 +50,7 @@
 
 static __strong NSMutableDictionary *authStateHandlers;
 static __strong NSMutableDictionary *idTokenHandlers;
+static __strong NSMutableDictionary *emulatorConfigs;
 // Used for caching credentials between method calls.
 static __strong NSMutableDictionary<NSString *, FIRAuthCredential *> *credentials;
 
@@ -69,6 +70,7 @@ - (id)init {
   dispatch_once(&onceToken, ^{
     authStateHandlers = [[NSMutableDictionary alloc] init];
     idTokenHandlers = [[NSMutableDictionary alloc] init];
+    emulatorConfigs = [[NSMutableDictionary alloc] init];
     credentials = [[NSMutableDictionary alloc] init];
   });
   return self;
@@ -940,7 +942,10 @@ - (void)invalidate {
                   : (FIRApp *)firebaseApp
                   : (nonnull NSString *)host
                   : (NSInteger)port) {
-  [[FIRAuth authWithApp:firebaseApp] useEmulatorWithHost:host port:port];
+  if (!emulatorConfigs[firebaseApp.name]) {
+    [[FIRAuth authWithApp:firebaseApp] useEmulatorWithHost:host port:port];
+    emulatorConfigs[firebaseApp.name] = @YES;
+  }
 }
 
 - (FIRAuthCredential *)getCredentialForProvider:(NSString *)provider

packages/database/android/src/main/java/io/invertase/firebase/database/UniversalFirebaseDatabaseCommon.java

@@ -46,9 +46,14 @@ static FirebaseDatabase getDatabaseForApp(String appName, String dbURL) {
     setDatabaseConfig(firebaseDatabase, appName, dbURL);
 
     HashMap emulatorConfig = getEmulatorConfig(appName, dbURL);
-    if (emulatorConfig != null) {
+
+    if (emulatorConfig != null && emulatorConfig.get("configured") == null) {
       firebaseDatabase.useEmulator(
           (String) emulatorConfig.get("host"), (Integer) emulatorConfig.get("port"));
+      // The underlying SDK may only be configured once, but with hot-reloads in the
+      // javascript bundle, javascript cannot hold SDK configuration state. Keep track here
+      // so we only configure once
+      emulatorConfig.put("configured", "true");
     }
 
     return firebaseDatabase;

packages/database/ios/RNFBDatabase/RNFBDatabaseModule.m

@@ -22,6 +22,8 @@
 #import "RNFBDatabaseModule.h"
 #import "RNFBPreferences.h"
 
+static __strong NSMutableDictionary *emulatorSettings;
+
 @implementation RNFBDatabaseModule
 #pragma mark -
 #pragma mark Module Setup
@@ -58,8 +60,22 @@ - (dispatch_queue_t)methodQueue {
                   : (NSString *)dbURL
                   : (nonnull NSString *)host
                   : (NSInteger)port) {
-  [[RNFBDatabaseCommon getDatabaseForApp:firebaseApp dbURL:dbURL] useEmulatorWithHost:host
-                                                                                 port:port];
+  // javascript may hot reload, losing state, and native throws an error if you double-request
+  // so we keep track of useEmulator calls here to avoid calling native twice
+  if (emulatorSettings == nil) {
+    emulatorSettings = [NSMutableDictionary dictionary];
+  }
+
+  NSMutableString *configKey = [firebaseApp.name mutableCopy];
+  if (dbURL != nil && dbURL.length > 0) {
+    [configKey appendString:dbURL];
+  }
+
+  if (!emulatorSettings[configKey]) {
+    [[RNFBDatabaseCommon getDatabaseForApp:firebaseApp dbURL:dbURL] useEmulatorWithHost:host
+                                                                                   port:port];
+    emulatorSettings[configKey] = @YES;
+  }
 }
 
 RCT_EXPORT_METHOD(setPersistenceEnabled

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

@@ -28,11 +28,14 @@
 import io.invertase.firebase.common.UniversalFirebaseModule;
 import io.invertase.firebase.common.UniversalFirebasePreferences;
 import java.nio.charset.StandardCharsets;
+import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 
 public class UniversalFirebaseFirestoreModule extends UniversalFirebaseModule {
 
+  private static HashMap<String, String> emulatorConfigs = new HashMap<>();
+
   UniversalFirebaseFirestoreModule(Context context, String serviceName) {
     super(context, serviceName);
   }
@@ -49,7 +52,10 @@ Task<Void> useEmulator(String appName, String host, int port) {
     return Tasks.call(
         getExecutor(),
         () -> {
-          getFirestoreForApp(appName).useEmulator(host, port);
+          if (emulatorConfigs.get(appName) == null) {
+            emulatorConfigs.put(appName, "true");
+            getFirestoreForApp(appName).useEmulator(host, port);
+          }
           return null;
         });
   }

packages/firestore/ios/RNFBFirestore/RNFBFirestoreModule.m

@@ -20,6 +20,8 @@
 #import "RNFBFirestoreCommon.h"
 #import "RNFBPreferences.h"
 
+NSMutableDictionary *emulatorConfigs;
+
 @implementation RNFBFirestoreModule
 #pragma mark -
 #pragma mark Module Setup
@@ -142,13 +144,19 @@ + (BOOL)requiresMainQueueSetup {
                   : (FIRApp *)firebaseApp
                   : (nonnull NSString *)host
                   : (NSInteger)port) {
-  FIRFirestore *firestore = [RNFBFirestoreCommon getFirestoreForApp:firebaseApp];
-  [firestore useEmulatorWithHost:host port:port];
-
-  // It is not sufficient to just use emulator. You have toggle SSL off too.
-  FIRFirestoreSettings *settings = firestore.settings;
-  settings.sslEnabled = FALSE;
-  firestore.settings = settings;
+  if (emulatorConfigs == nil) {
+    emulatorConfigs = [[NSMutableDictionary alloc] init];
+  }
+  if (!emulatorConfigs[firebaseApp.name]) {
+    FIRFirestore *firestore = [RNFBFirestoreCommon getFirestoreForApp:firebaseApp];
+    [firestore useEmulatorWithHost:host port:port];
+    emulatorConfigs[firebaseApp.name] = @YES;
+
+    // It is not sufficient to just use emulator. You have toggle SSL off too.
+    FIRFirestoreSettings *settings = firestore.settings;
+    settings.sslEnabled = FALSE;
+    firestore.settings = settings;
+  }
 }
 
 RCT_EXPORT_METHOD(waitForPendingWrites

packages/storage/android/src/main/java/io/invertase/firebase/storage/ReactNativeFirebaseStorageModule.java

@@ -44,6 +44,8 @@
 public class ReactNativeFirebaseStorageModule extends ReactNativeFirebaseModule {
   private static final String TAG = "Storage";
 
+  private static HashMap<String, String> emulatorConfigs = new HashMap<>();
+
   ReactNativeFirebaseStorageModule(ReactApplicationContext reactContext) {
     super(reactContext, TAG);
   }
@@ -54,7 +56,9 @@ public void onCatalystInstanceDestroy() {
     super.onCatalystInstanceDestroy();
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#delete */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#delete
+   */
   @ReactMethod
   public void delete(String appName, String url, final Promise promise) {
     try {
@@ -97,7 +101,9 @@ public void getDownloadURL(String appName, final String url, final Promise promi
     }
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#getMetadata */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#getMetadata
+   */
   @ReactMethod
   public void getMetadata(String appName, String url, Promise promise) {
     try {
@@ -118,7 +124,9 @@ public void getMetadata(String appName, String url, Promise promise) {
     }
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#list */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#list
+   */
   @ReactMethod
   public void list(String appName, String url, ReadableMap listOptions, Promise promise) {
     try {
@@ -148,7 +156,9 @@ public void list(String appName, String url, ReadableMap listOptions, Promise pr
     }
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#listAll */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#listAll
+   */
   @ReactMethod
   public void listAll(String appName, String url, Promise promise) {
     try {
@@ -267,16 +277,23 @@ public void setMaxUploadRetryTime(String appName, double milliseconds, Promise p
     promise.resolve(null);
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Storage#useEmulator */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Storage#useEmulator
+   */
   @ReactMethod
   public void useEmulator(String appName, String host, int port, Promise promise) {
     FirebaseApp firebaseApp = FirebaseApp.getInstance(appName);
     FirebaseStorage firebaseStorage = FirebaseStorage.getInstance(firebaseApp);
-    firebaseStorage.useEmulator(host, port);
+    if (emulatorConfigs.get(appName) == null) {
+      firebaseStorage.useEmulator(host, port);
+      emulatorConfigs.put(appName, "true");
+    }
     promise.resolve(null);
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#writeToFile */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#writeToFile
+   */
   @ReactMethod
   public void writeToFile(
       String appName, String url, String localFilePath, int taskId, Promise promise) {
@@ -300,7 +317,9 @@ public void writeToFile(
     }
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#putString */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#putString
+   */
   @ReactMethod
   public void putString(
       String appName,
@@ -321,7 +340,9 @@ public void putString(
     }
   }
 
-  /** @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#putFile */
+  /**
+   * @link https://firebase.google.com/docs/reference/js/firebase.storage.Reference#putFile
+   */
   @ReactMethod
   public void putFile(
       String appName,

packages/storage/ios/RNFBStorage/RNFBStorageModule.m

@@ -35,7 +35,7 @@
 // The iOS SDK has a short memory on settings, store these globally and set them in each time
 static NSString *emulatorHost = nil;
 static NSInteger emulatorPort = 0;
-static bool useEmulatorCalled = false;
+static NSMutableDictionary *emulatorConfigs;
 static NSTimeInterval maxDownloadRetryTime = 600;
 static NSTimeInterval maxUploadRetryTime = 600;
 static NSTimeInterval maxOperationRetryTime = 120;
@@ -56,6 +56,7 @@ - (id)init {
   static dispatch_once_t onceToken;
   dispatch_once(&onceToken, ^{
     PENDING_TASKS = [[NSMutableDictionary alloc] init];
+    emulatorConfigs = [[NSMutableDictionary alloc] init];
   });
 
   return self;
@@ -506,12 +507,10 @@ - (void)invalidate {
                   : (NSInteger)port) {
   emulatorHost = host;
   emulatorPort = port;
-  if (useEmulatorCalled == true) {
-    return;
+  if (!emulatorConfigs[firebaseApp.name]) {
+    [[FIRStorage storageForApp:firebaseApp] useEmulatorWithHost:host port:port];
+    emulatorConfigs[firebaseApp.name] = @YES;
   }
-
-  [[FIRStorage storageForApp:firebaseApp] useEmulatorWithHost:host port:port];
-  useEmulatorCalled = true;
 }
 
 /**
@@ -669,10 +668,11 @@ - (FIRStorageReference *)getReferenceFromUrl:(NSString *)url app:(FIRApp *)fireb
   storage = [FIRStorage storageForApp:firebaseApp URL:bucket];
 
   NSLog(@"Setting emulator - host %@ port %ld", emulatorHost, (long)emulatorPort);
-  if (![emulatorHost isEqual:[NSNull null]] && emulatorHost != nil && useEmulatorCalled == false) {
+  if (![emulatorHost isEqual:[NSNull null]] && emulatorHost != nil &&
+      !emulatorConfigs[firebaseApp.name]) {
     @try {
       [storage useEmulatorWithHost:emulatorHost port:emulatorPort];
-      useEmulatorCalled = true;
+      emulatorConfigs[firebaseApp.name] = @YES;
     } @catch (NSException *e) {
       NSLog(@"WARNING: Unable to set the Firebase Storage emulator settings. These must be set "
             @"before any usages of Firebase Storage. If you see this log after a hot "