[ios][database] New implementation for off and on to match Android

ios/RNFirebase/database/RNFirebaseDatabase.h

@@ -18,6 +18,8 @@
 
 + (FIRDatabase *)getDatabaseForApp:(NSString *)appName;
 
++ (NSDictionary *)getJSError:(NSError *)nativeError;
+
 + (NSString *)getMessageWithService:(NSString *)message service:(NSString *)service fullCode:(NSString *)fullCode;
 
 + (NSString *)getCodeWithService:(NSString *)service code:(NSString *)code;

ios/RNFirebase/database/RNFirebaseDatabase.m

@@ -21,42 +21,31 @@ RCT_EXPORT_MODULE();
     return self;
 }
 
-RCT_EXPORT_METHOD(goOnline:
+RCT_EXPORT_METHOD(goOnline:(NSString *) appName) {
-    (NSString *) appName) {
     [[RNFirebaseDatabase getDatabaseForApp:appName] goOnline];
 }
 
-RCT_EXPORT_METHOD(goOffline:
+RCT_EXPORT_METHOD(goOffline:(NSString *) appName) {
-    (NSString *) appName) {
     [[RNFirebaseDatabase getDatabaseForApp:appName] goOffline];
 }
 
-RCT_EXPORT_METHOD(setPersistence:
+RCT_EXPORT_METHOD(setPersistence:(NSString *) appName
-    (NSString *) appName
+                           state:(BOOL) state) {
-            state:
-            (BOOL) state) {
     [RNFirebaseDatabase getDatabaseForApp:appName].persistenceEnabled = state;
 }
 
-RCT_EXPORT_METHOD(keepSynced:
+RCT_EXPORT_METHOD(keepSynced:(NSString *) appName
-    (NSString *) appName
+                         key:(NSString *) key
-            refId:
+                        path:(NSString *) path
-            (nonnull
+                   modifiers:(NSArray *) modifiers
-        NSNumber *) refId
+                       state:(BOOL) state) {
-        path:(NSString *) path
+    FIRDatabaseQuery *query = [self getInternalReferenceForApp:appName key:key path:path modifiers:modifiers keep:false].query;
-        modifiers:(NSArray *) modifiers
-        state:(BOOL) state) {
-
-    FIRDatabaseQuery *query = [self getInternalReferenceForApp:appName refId:refId path:path modifiers:modifiers keep:false].query;
     [query keepSynced:state];
 }
 
-RCT_EXPORT_METHOD(transactionTryCommit:
+RCT_EXPORT_METHOD(transactionTryCommit:(NSString *) appName
-    (NSString *) appName
+                         transactionId:(nonnull NSNumber *) transactionId
-            transactionId:
+                               updates:(NSDictionary *) updates) {
-            (nonnull
-        NSNumber *) transactionId
-        updates:(NSDictionary *) updates) {
     __block NSMutableDictionary *transactionState;
 
     dispatch_sync(_transactionQueue, ^{
@@ -83,14 +72,10 @@ RCT_EXPORT_METHOD(transactionTryCommit:
 }
 
 
-RCT_EXPORT_METHOD(transactionStart:
+RCT_EXPORT_METHOD(transactionStart:(NSString *) appName
-    (NSString *) appName
+                              path:(NSString *) path
-            path:
+                     transactionId:(nonnull NSNumber *) transactionId
-            (NSString *) path
+                      applyLocally:(BOOL) applyLocally) {
-            transactionId:
-            (nonnull
-        NSNumber *) transactionId
-        applyLocally:(BOOL) applyLocally) {
     dispatch_async(_transactionQueue, ^{
         NSMutableDictionary *transactionState = [NSMutableDictionary new];
         dispatch_semaphore_t sema = dispatch_semaphore_create(0);
@@ -136,160 +121,132 @@ RCT_EXPORT_METHOD(transactionStart:
     });
 }
 
-RCT_EXPORT_METHOD(onDisconnectSet:
+RCT_EXPORT_METHOD(onDisconnectSet:(NSString *) appName
-    (NSString *) appName
+                             path:(NSString *) path
-            path:
+                            props:(NSDictionary *) props
-            (NSString *) path
+                         resolver:(RCTPromiseResolveBlock) resolve
-            props:
+                         rejecter:(RCTPromiseRejectBlock) reject) {
-            (NSDictionary *) props
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref onDisconnectSetValue:props[@"value"] withCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull _ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(onDisconnectUpdate:
+RCT_EXPORT_METHOD(onDisconnectUpdate:(NSString *) appName
-    (NSString *) appName
+                                path:(NSString *) path
-            path:
+                               props:(NSDictionary *) props
-            (NSString *) path
+                            resolver:(RCTPromiseResolveBlock) resolve
-            props:
+                            rejecter:(RCTPromiseRejectBlock) reject) {
-            (NSDictionary *) props
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref onDisconnectUpdateChildValues:props withCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull _ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(onDisconnectRemove:
+RCT_EXPORT_METHOD(onDisconnectRemove:(NSString *) appName
-    (NSString *) appName
+                                path:(NSString *) path
-            path:
+                            resolver:(RCTPromiseResolveBlock) resolve
-            (NSString *) path
+                            rejecter:(RCTPromiseRejectBlock) reject) {
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref onDisconnectRemoveValueWithCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull _ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(onDisconnectCancel:
+RCT_EXPORT_METHOD(onDisconnectCancel:(NSString *) appName
-    (NSString *) appName
+                                path:(NSString *) path
-            path:
+                            resolver:(RCTPromiseResolveBlock) resolve
-            (NSString *) path
+                            rejecter:(RCTPromiseRejectBlock) reject) {
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref cancelDisconnectOperationsWithCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull _ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(set:
+RCT_EXPORT_METHOD(set:(NSString *) appName
-    (NSString *) appName
+                 path:(NSString *) path
-            path:
+                props:(NSDictionary *) props
-            (NSString *) path
+             resolver:(RCTPromiseResolveBlock) resolve
-            props:
+             rejecter:(RCTPromiseRejectBlock) reject) {
-            (NSDictionary *) props
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref setValue:[props valueForKey:@"value"] withCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull _ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(setPriority:
+RCT_EXPORT_METHOD(setPriority:(NSString *) appName
-    (NSString *) appName
+                         path:(NSString *) path
-            path:
+                     priority:(NSDictionary *) priority
-            (NSString *) path
+                     resolver:(RCTPromiseResolveBlock) resolve
-            priority:
+                     rejecter:(RCTPromiseRejectBlock) reject) {
-            (NSDictionary *) priority
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref setPriority:[priority valueForKey:@"value"] withCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(setWithPriority:
+RCT_EXPORT_METHOD(setWithPriority:(NSString *) appName
-    (NSString *) appName
+                             path:(NSString *) path
-            path:
+                             data:(NSDictionary *) data
-            (NSString *) path
+                         priority:(NSDictionary *) priority
-            data:
+                         resolver:(RCTPromiseResolveBlock) resolve
-            (NSDictionary *) data
+                         rejecter:(RCTPromiseRejectBlock) reject) {
-            priority:
-            (NSDictionary *) priority
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref setValue:[data valueForKey:@"value"] andPriority:[priority valueForKey:@"value"] withCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(update:
+RCT_EXPORT_METHOD(update:(NSString *) appName
-    (NSString *) appName
+                    path:(NSString *) path
-            path:
+                   props:(NSDictionary *) props
-            (NSString *) path
+                resolver:(RCTPromiseResolveBlock) resolve
-            props:
+                rejecter:(RCTPromiseRejectBlock) reject) {
-            (NSDictionary *) props
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref updateChildValues:props withCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull _ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(remove:
+RCT_EXPORT_METHOD(remove:(NSString *) appName
-    (NSString *) appName
+                    path:(NSString *) path
-            path:
+                resolver:(RCTPromiseResolveBlock) resolve
-            (NSString *) path
+                rejecter:(RCTPromiseRejectBlock) reject) {
-            resolver:
-            (RCTPromiseResolveBlock) resolve
-            rejecter:
-            (RCTPromiseRejectBlock) reject) {
     FIRDatabaseReference *ref = [self getReferenceForAppPath:appName path:path];
     [ref removeValueWithCompletionBlock:^(NSError *_Nullable error, FIRDatabaseReference *_Nonnull _ref) {
         [RNFirebaseDatabase handlePromise:resolve rejecter:reject databaseError:error];
     }];
 }
 
-RCT_EXPORT_METHOD(once:
+RCT_EXPORT_METHOD(once:(NSString *) appName
-    (NSString *) appName
+                   key:(NSString *) key
-            refId:
+                  path:(NSString *) path
-            (nonnull
+             modifiers:(NSArray *) modifiers
-        NSNumber *) refId
+             eventName:(NSString *) eventName
-        path:(NSString *) path
+              resolver:(RCTPromiseResolveBlock) resolve
-        modifiers:(NSArray *) modifiers
+              rejecter:(RCTPromiseRejectBlock) reject) {
-        eventName:(NSString *) eventName
+    RNFirebaseDatabaseReference *ref = [self getInternalReferenceForApp:appName key:key path:path modifiers:modifiers keep:false];
-        resolver:(RCTPromiseResolveBlock) resolve
+    [ref once:eventName resolver:resolve rejecter:reject];
-        rejecter:(RCTPromiseRejectBlock) reject) {
-    RNFirebaseDatabaseReference *ref = [self getInternalReferenceForApp:appName refId:refId path:path modifiers:modifiers keep:false];
-    [ref addSingleEventHandler:eventName resolver:resolve rejecter:reject];
 }
 
+RCT_EXPORT_METHOD(on:(NSString *) appName
+               props:(NSDictionary *) props) {
+    RNFirebaseDatabaseReference *ref = [self getInternalReferenceForApp:appName key:props[@"key"] path:props[@"path"] modifiers:props[@"modifiers"] keep:false];
+    [ref on:props[@"eventType"] registration:props[@"registration"]];
+}
+
+RCT_EXPORT_METHOD(off:(NSString *) key
+ eventRegistrationKey:(NSString *) eventRegistrationKey) {
+    RNFirebaseDatabaseReference *ref = _dbReferences[key];
+    [ref removeEventListener:eventRegistrationKey];
+    
+    if (![ref hasListeners]) {
+        [_dbReferences removeObjectForKey:key];
+    }
+}
+
+
+
 /*
  * INTERNALS/UTILS
  */
@@ -311,14 +268,14 @@ RCT_EXPORT_METHOD(once:
     return [[RNFirebaseDatabase getDatabaseForApp:appName] referenceWithPath:path];
 }
 
-- (RNFirebaseDatabaseReference *)getInternalReferenceForApp:(NSString *)appName refId:(NSNumber *)refId path:(NSString *)path modifiers:(NSArray *)modifiers keep:(BOOL)keep {
+- (RNFirebaseDatabaseReference *)getInternalReferenceForApp:(NSString *)appName key:(NSString *)key path:(NSString *)path modifiers:(NSArray *)modifiers keep:(BOOL)keep {
-    RNFirebaseDatabaseReference *ref = _dbReferences[refId];
+    RNFirebaseDatabaseReference *ref = _dbReferences[key];
 
     if (ref == nil) {
-        ref = [[RNFirebaseDatabaseReference alloc] initWithPathAndModifiers:self app:appName refId:refId refPath:path modifiers:modifiers];
+        ref = [[RNFirebaseDatabaseReference alloc] initWithPathAndModifiers:self app:appName key:key refPath:path modifiers:modifiers];
 
         if (keep) {
-            _dbReferences[refId] = ref;
+            _dbReferences[key] = ref;
         }
     }
     return ref;
@@ -435,47 +392,6 @@ RCT_EXPORT_METHOD(once:
     return resultMap;
 }
 
-
-RCT_EXPORT_METHOD(on:(NSString *) appName  args:(NSDictionary *) args) {
-    // todo
-//    RNFirebaseDatabaseReference *ref = [self getInternalReferenceForApp:appName refId:refId path:path modifiers:modifiers keep:false];
-//     TODO query identifier
-//    [ref addEventHandler:listenerId eventName:eventName];
-}
-
-/* TODO
-
-RCT_EXPORT_METHOD(off:
-    (nonnull
-        NSNumber *) refId
-        listeners:(NSArray *) listeners
-        callback:(RCTResponseSenderBlock) callback) {
-    RNFirebaseDatabaseReference *ref = _dbReferences[refId];
-    if (ref != nil) {
-        for (NSDictionary *listener in listeners) {
-            NSNumber *listenerId = [listener valueForKey:@"listenerId"];
-            NSString *eventName = [listener valueForKey:@"eventName"];
-            [ref removeEventHandler:listenerId eventName:eventName];
-            if (![ref hasListeners]) {
-                [_dbReferences removeObjectForKey:refId];
-            }
-        }
-    }
-    callback(@[[NSNull null], @{@"status": @"success", @"refId": refId,}]);
-}
-
-
-- (RNFirebaseDatabaseReference *)getDBHandle:(NSNumber *)refId path:(NSString *)path modifiers:(NSArray *)modifiers {
-    RNFirebaseDatabaseReference *ref = _dbReferences[refId];
-
-    if (ref == nil) {
-        ref = [[RNFirebaseDatabaseReference alloc] initWithPathAndModifiers:self database:[FIRDatabase database] refId:refId path:path modifiers:modifiers];
-        _dbReferences[refId] = ref;
-    }
-    return ref;
-} */
-
-
 - (NSArray<NSString *> *)supportedEvents {
     return @[DATABASE_SYNC_EVENT, DATABASE_TRANSACTION_EVENT];
 }

ios/RNFirebase/database/RNFirebaseDatabaseReference.h

@@ -12,16 +12,16 @@
 @property RCTEventEmitter *emitter;
 @property FIRDatabaseQuery *query;
 @property NSString *app;
-@property NSNumber *refId;
+@property NSString *key;
 @property NSString *path;
 @property NSMutableDictionary *listeners;
 
-- (id)initWithPathAndModifiers:(RCTEventEmitter *)emitter app:(NSString *)app refId:(NSNumber *)refId refPath:(NSString *)refPath modifiers:(NSArray *)modifiers;
+- (id)initWithPathAndModifiers:(RCTEventEmitter *)emitter app:(NSString *)app key:(NSString *)key refPath:(NSString *)refPath modifiers:(NSArray *)modifiers;
-- (void)addEventHandler:(NSNumber *)listenerId eventName:(NSString *)eventName;
+- (void)on:(NSString *) eventName registration:(NSDictionary *) registration;
-- (void)addSingleEventHandler:(NSString *)eventName resolver:(RCTPromiseResolveBlock) resolve rejecter:(RCTPromiseRejectBlock) reject;
+- (void)once:(NSString *) eventType resolver:(RCTPromiseResolveBlock) resolve rejecter:(RCTPromiseRejectBlock) reject;
-- (void)removeEventHandler:(NSNumber *)listenerId eventName:(NSString *)eventName;
+- (void)removeEventListener:(NSString *)eventRegistrationKey;
 - (BOOL)hasListeners;
-+ (NSDictionary *)snapshotToDict:(FIRDataSnapshot *)snapshot;
++ (NSDictionary *)snapshotToDict:(FIRDataSnapshot *)dataSnapshot;
 @end
 
 #else

ios/RNFirebase/database/RNFirebaseDatabaseReference.m

@@ -6,50 +6,52 @@
 
 - (id)initWithPathAndModifiers:(RCTEventEmitter *)emitter
                            app:(NSString *) app
-                         refId:(NSNumber *) refId
+                           key:(NSString *) key
                        refPath:(NSString *) refPath
                      modifiers:(NSArray *) modifiers {
     self = [super init];
     if (self) {
         _emitter = emitter;
         _app = app;
-        _refId = refId;
+        _key = key;
         _path = refPath;
-
-        // TODO: Only create if needed
         _listeners = [[NSMutableDictionary alloc] init];
-
         _query = [self buildQueryAtPathWithModifiers:refPath modifiers:modifiers];
     }
     return self;
 }
 
-- (void)addEventHandler:(NSNumber *)listenerId eventName:(NSString *)eventName {
+- (void)removeEventListener:(NSString *)eventRegistrationKey {
-    if (!_listeners[listenerId]) {
+    FIRDatabaseHandle handle = (FIRDatabaseHandle) [_listeners[eventRegistrationKey] integerValue];
-        id andPreviousSiblingKeyWithBlock = ^(FIRDataSnapshot *_Nonnull snapshot, NSString *_Nullable previousChildName) {
+    if (handle) {
-            NSDictionary *props = [RNFirebaseDatabaseReference snapshotToDict:snapshot];
+        [_query removeObserverWithHandle:handle];
-            [self sendJSEvent:DATABASE_SYNC_EVENT title:eventName props:@{@"eventName": eventName, @"refId": _refId, @"listenerId": listenerId, @"path": _path, @"snapshot": props, @"previousChildName": previousChildName != nil ? previousChildName : [NSNull null]}];
+        [_listeners removeObjectForKey:eventRegistrationKey];
-        };
-        id errorBlock = ^(NSError *_Nonnull error) {
-            NSLog(@"Error onDBEvent: %@", [error debugDescription]);
-            [self removeEventHandler:listenerId eventName:eventName];
-            [self getAndSendDatabaseError:error listenerId:listenerId];
-        };
-        int eventType = [self eventTypeFromName:eventName];
-        FIRDatabaseHandle handle = [_query observeEventType:eventType andPreviousSiblingKeyWithBlock:andPreviousSiblingKeyWithBlock withCancelBlock:errorBlock];
-        _listeners[listenerId] = @(handle);
-    } else {
-        NSLog(@"Warning Trying to add duplicate listener for refId: %@ listenerId: %@", _refId, listenerId);
     }
 }
 
-- (void)addSingleEventHandler:(NSString *)eventName
+- (void)on:(NSString *) eventType registration:(NSDictionary *) registration {
-                     resolver:(RCTPromiseResolveBlock) resolve
+    NSString *eventRegistrationKey = registration[@"eventRegistrationKey"];
-                     rejecter:(RCTPromiseRejectBlock) reject {
+    if (![self hasEventListener:eventRegistrationKey]) {
-    FIRDataEventType firDataEventType = (FIRDataEventType)[self eventTypeFromName:eventName];
+        id andPreviousSiblingKeyWithBlock = ^(FIRDataSnapshot *_Nonnull snapshot, NSString *_Nullable previousChildName) {
+            [self handleDatabaseEvent:eventType registration:registration dataSnapshot:snapshot previousChildName:previousChildName];
+        };
+        id errorBlock = ^(NSError *_Nonnull error) {
+            NSLog(@"Error onDBEvent: %@", [error debugDescription]);
+            [self removeEventListener:eventRegistrationKey];
+            [self handleDatabaseError:registration error:error];
+        };
+        FIRDataEventType firDataEventType = (FIRDataEventType)[self eventTypeFromName:eventType];
+        FIRDatabaseHandle handle = [_query observeEventType:firDataEventType andPreviousSiblingKeyWithBlock:andPreviousSiblingKeyWithBlock withCancelBlock:errorBlock];
+        _listeners[eventRegistrationKey] = @(handle);
+    }
+}
 
+- (void)once:(NSString *) eventType
+    resolver:(RCTPromiseResolveBlock) resolve
+    rejecter:(RCTPromiseRejectBlock) reject {
+    FIRDataEventType firDataEventType = (FIRDataEventType)[self eventTypeFromName:eventType];
     [_query observeSingleEventOfType:firDataEventType andPreviousSiblingKeyWithBlock:^(FIRDataSnapshot *_Nonnull snapshot, NSString *_Nullable previousChildName) {
-        NSDictionary *data = [RNFirebaseDatabaseReference snapshotToDictionary:eventName path:_path dataSnapshot:snapshot previousChildName:previousChildName refId:_refId listenerId:0];
+        NSDictionary *data = [RNFirebaseDatabaseReference snapshotToDictionary:snapshot previousChildName:previousChildName];
         resolve(data);
     } withCancelBlock:^(NSError *_Nonnull error) {
         NSLog(@"Error onDBEventOnce: %@", [error debugDescription]);
@@ -57,39 +59,54 @@
     }];
 }
 
-- (void)removeEventHandler:(NSNumber *)listenerId eventName:(NSString *)eventName {
+- (void)handleDatabaseEvent:(NSString *) eventType
-    FIRDatabaseHandle handle = (FIRDatabaseHandle) [_listeners[listenerId] integerValue];
+               registration:(NSDictionary *) registration
-    if (handle) {
+               dataSnapshot:(FIRDataSnapshot *) dataSnapshot
-        [_listeners removeObjectForKey:listenerId];
+          previousChildName:(NSString *) previousChildName {
-        [_query removeObserverWithHandle:handle];
+    NSMutableDictionary *event = [[NSMutableDictionary alloc] init];
-    }
+    NSDictionary *data = [RNFirebaseDatabaseReference snapshotToDictionary:dataSnapshot previousChildName:previousChildName];
+    
+    [event setValue:data forKey:@"data"];
+    [event setValue:_key forKey:@"key"];
+    [event setValue:eventType forKey:@"eventType"];
+    [event setValue:registration forKey:@"registration"];
+    
+    [_emitter sendEventWithName:DATABASE_SYNC_EVENT body:event];
 }
 
-+ (NSDictionary *) snapshotToDictionary:(NSString *) eventName
+- (void)handleDatabaseError:(NSDictionary *) registration
-                                   path:(NSString *) path
+                      error:(NSError *)error {
-                           dataSnapshot:(FIRDataSnapshot *) dataSnapshot
+    NSMutableDictionary *event = [[NSMutableDictionary alloc] init];
-                      previousChildName:(NSString *) previousChildName
+    [event setValue:_key forKey:@"key"];
-                                  refId:(NSNumber *) refId
+    [event setValue:[RNFirebaseDatabase getJSError:error] forKey:@"error"];
-                             listenerId:(NSNumber *) listenerId {
+    [event setValue:registration forKey:@"registration"];
+    
+    [_emitter sendEventWithName:DATABASE_SYNC_EVENT body:event];
+}
+
++ (NSDictionary *)snapshotToDictionary:(FIRDataSnapshot *) dataSnapshot
+                     previousChildName:(NSString *) previousChildName {
+    NSMutableDictionary *result = [[NSMutableDictionary alloc] init];
+    NSDictionary *snapshot = [RNFirebaseDatabaseReference snapshotToDict:dataSnapshot];
+
+    [result setValue:snapshot forKey:@"snapshot"];
+    [result setValue:previousChildName forKey:@"previousChildName"];
+
+    return result;
+}
+
++ (NSDictionary *)snapshotToDict:(FIRDataSnapshot *)dataSnapshot {
     NSMutableDictionary *snapshot = [[NSMutableDictionary alloc] init];
-    NSMutableDictionary *eventMap = [[NSMutableDictionary alloc] init];
     
     [snapshot setValue:dataSnapshot.key forKey:@"key"];
     [snapshot setValue:@(dataSnapshot.exists) forKey:@"exists"];
     [snapshot setValue:@(dataSnapshot.hasChildren) forKey:@"hasChildren"];
     [snapshot setValue:@(dataSnapshot.childrenCount) forKey:@"childrenCount"];
-    [snapshot setValue:dataSnapshot.value forKey:@"value"];
     [snapshot setValue:[RNFirebaseDatabaseReference getChildKeys:dataSnapshot] forKey:@"childKeys"];
     [snapshot setValue:dataSnapshot.priority forKey:@"priority"];
+    [snapshot setValue:dataSnapshot.value forKey:@"value"];
     
-    [eventMap setValue:refId forKey:@"refId"];
+    return snapshot;
-    [eventMap setValue:path forKey:@"path"];
-    [eventMap setValue:snapshot forKey:@"snapshot"];
-    [eventMap setValue:eventName forKey:@"eventName"];
-    [eventMap setValue:listenerId forKey:@"listenerId"];
-    [eventMap setValue:previousChildName forKey:@"previousChildName"];
-
-    return eventMap;
 }
 
 + (NSMutableArray *) getChildKeys:(FIRDataSnapshot *) snapshot {
@@ -104,53 +121,6 @@
     return childKeys;
 }
 
-+ (NSDictionary *)snapshotToDict:(FIRDataSnapshot *)snapshot {
-    NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
-    [dict setValue:snapshot.key forKey:@"key"];
-    NSDictionary *val = snapshot.value;
-    dict[@"value"] = val;
-    // Snapshot ordering
-    NSMutableArray *childKeys = [NSMutableArray array];
-    if (snapshot.childrenCount > 0) {
-        // Since JS does not respect object ordering of keys
-        // we keep a list of the keys and their ordering
-        // in the snapshot event
-        NSEnumerator *children = [snapshot children];
-        FIRDataSnapshot *child;
-        while (child = [children nextObject]) {
-            [childKeys addObject:child.key];
-        }
-    }
-    dict[@"childKeys"] = childKeys;
-    [dict setValue:@(snapshot.hasChildren) forKey:@"hasChildren"];
-    [dict setValue:@(snapshot.exists) forKey:@"exists"];
-    [dict setValue:@(snapshot.childrenCount) forKey:@"childrenCount"];
-    [dict setValue:snapshot.priority forKey:@"priority"];
-    return dict;
-}
-
-- (NSDictionary *)getAndSendDatabaseError:(NSError *)error listenerId:(NSNumber *)listenerId {
-    NSDictionary *event = @{@"eventName": DATABASE_SYNC_EVENT, @"path": _path, @"refId": _refId, @"listenerId": listenerId, @"code": @([error code]), @"details": [error debugDescription], @"message": [error localizedDescription], @"description": [error description]};
-
-    @try {
-        [_emitter sendEventWithName:DATABASE_SYNC_EVENT body:event];
-    } @catch (NSException *err) {
-        NSLog(@"An error occurred in getAndSendDatabaseError: %@", [err debugDescription]);
-        NSLog(@"Tried to send: %@ with %@", DATABASE_SYNC_EVENT, event);
-    }
-
-    return event;
-}
-
-- (void)sendJSEvent:(NSString *)type title:(NSString *)title props:(NSDictionary *)props {
-    @try {
-        [_emitter sendEventWithName:type body:@{@"eventName": title, @"body": props}];
-    } @catch (NSException *err) {
-        NSLog(@"An error occurred in sendJSEvent: %@", [err debugDescription]);
-        NSLog(@"Tried to send: %@ with %@", title, props);
-    }
-}
-
 - (FIRDatabaseQuery *)buildQueryAtPathWithModifiers:(NSString *) path
                                           modifiers:(NSArray *)modifiers {
     FIRDatabase *firebaseDatabase = [RNFirebaseDatabase getDatabaseForApp:_app];
@@ -216,6 +186,10 @@
     }
 }
 
+- (BOOL)hasEventListener:(NSString *) eventRegistrationKey {
+    return _listeners[eventRegistrationKey] != nil;
+}
+
 - (BOOL)hasListeners {
     return [[_listeners allKeys] count] > 0;
 }