fix(storage, emulator): avoid calling useEmulator multiple times

In case of javascript hot reload, javascript will attempt to call useEmulator again,
and the native layer will complain about the second call. This avoids the second call
by tracking useEmulator call state at the native layer

Fixes #5860 (again, but this time per-app, and for android as well)

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);
   }
@@ -282,7 +284,10 @@ public void setMaxUploadRetryTime(String appName, double milliseconds, Promise p
   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);
   }
 

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 "