Support for ref.once('child_added')

Author: FrankSalad

ios/Firestack/FirestackDatabase.m

@@ -42,6 +42,12 @@ - (id) initWithPathAndModifiers:(RCTEventEmitter *) emitter
   return self;
 }
 
+- (NSString *) absPath:(FIRDatabaseReference *) ref {
+    NSString *url = ref.URL;
+    NSString *rooturl = ref.root.URL;
+    return [[url substringFromIndex:rooturl.length] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
+}
+
 - (void) addEventHandler:(NSString *) eventName
 {
     if (![self isListeningTo:eventName]) {
@@ -51,7 +57,7 @@ - (void) addEventHandler:(NSString *) eventName
                         title:eventName
                         props: @{
                                  @"eventName": eventName,
-                                 @"path": _path,
+                                 @"path": [self absPath:[snapshot ref]],
                                  @"modifiersString": _modifiersString,
                                  @"snapshot": props
                                  }];
@@ -71,13 +77,15 @@ - (void) addEventHandler:(NSString *) eventName
 }
 
 - (void) addSingleEventHandler:(RCTResponseSenderBlock) callback
+                        ofType:(NSString *) type
 {
-    [_query observeSingleEventOfType:FIRDataEventTypeValue
+    int eventType = [self eventTypeFromName:type];
+    [_query observeSingleEventOfType:eventType
                            withBlock:^(FIRDataSnapshot * _Nonnull snapshot) {
-                               NSDictionary *props = [self snapshotToDict:snapshot];
+                               NSDictionary *props = [FirestackDBReference snapshotToDict:snapshot];
                                callback(@[[NSNull null], @{
-                                              @"eventName": @"value",
-                                              @"path": _path,
+                                              @"eventName": type,
+                                              @"path": [self absPath:[snapshot ref]],
                                               @"modifiersString": _modifiersString,
                                               @"snapshot": props
                                               }]);
@@ -489,7 +497,7 @@ - (id) init
                 callback:(RCTResponseSenderBlock) callback)
 {
     FirestackDBReference *ref = [self getDBHandle:path modifiers:modifiers modifiersString:modifiersString];
-    [ref addSingleEventHandler:callback];
+    [ref addSingleEventHandler:callback ofType:name];
 }
 
 RCT_EXPORT_METHOD(off:(NSString *)path

lib/modules/database/reference.js

@@ -120,7 +120,9 @@ export default class Reference extends ReferenceBase {
     const modifiers = this.query.getModifiers();
     const modifiersString = this.query.getModifiersString();
     return promisify('onOnce', FirestackDatabase)(path, modifiersString, modifiers, eventName)
-      .then(({ snapshot }) => new Snapshot(this, snapshot))
+      .then(({ snapshot, path, modifiersString}) => new Snapshot(
+        new Reference(this.db, path.split('/'), modifiersString.split('|')),
+        snapshot))
       .then((snapshot) => {
         if (isFunction(cb)) cb(snapshot);
         return snapshot;