Add JsonGetObjectSize()

Author: Nikita Glukhov

src/backend/utils/adt/json_generic.c

@@ -282,6 +282,27 @@ jsonGetArraySize(JsonContainer *array)
 	return size;
 }
 
+uint32
+JsonGetObjectSize(JsonContainer *object)
+{
+	JsonValue		    val;
+	JsonIterator	   *it;
+	JsonIteratorToken	tok;
+	uint32				size = 0;
+
+	Assert(JsonContainerIsObject(object));
+
+	it = JsonIteratorInit(object);
+
+	while ((tok = JsonIteratorNext(&it, &val, true)) != WJB_DONE)
+	{
+		if (tok == WJB_KEY)
+			size++;
+	}
+
+	return size;
+}
+
 static void
 jsonvInitContainer(JsonContainerData *jc, const JsonValue *val)
 {

src/include/utils/json_generic.h

@@ -524,6 +524,7 @@ extern JsonValue   *jsonFindLastKeyInObject(JsonContainer *obj, const char *key,
 extern JsonValue   *jsonFindValueInArray(JsonContainer *array, const JsonValue *elem);
 extern uint32		jsonGetArraySize(JsonContainer *array);
 extern JsonValue   *jsonGetArrayElement(JsonContainer *array, uint32 index);
+extern uint32		JsonGetObjectSize(JsonContainer *object);
 
 extern bool JsonValueScalarEquals(const JsonValue *aScalar,
 								  const JsonValue *bScalar);