chore: import upstream snapshot with attribution

2026-07-13 13:02:50 +08:00
commit 0fc60fdcb1
5008 changed files with 910633 additions and 0 deletions
@@ -0,0 +1,71 @@
+/*
+ * QUANTCONNECT.COM - Democratizing Finance, Empowering Individuals.
+ * Lean Algorithmic Trading Engine v2.0. Copyright 2014 QuantConnect Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+*/
+
+using System;
+using Newtonsoft.Json;
+
+namespace QuantConnect.Util
+{
+    /// <summary>
+    /// Defines a <see cref="JsonConverter"/> that serializes <see cref="DateTime"/> use the number of whole and fractional seconds since unix epoch
+    /// </summary>
+    public class DoubleUnixSecondsDateTimeJsonConverter : TypeChangeJsonConverter<DateTime?, double?>
+    {
+        private static readonly DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
+
+        /// <summary>
+        /// Determines whether this instance can convert the specified object type.
+        /// </summary>
+        /// <param name="objectType">Type of the object.</param>
+        /// <returns>
+        /// <c>true</c> if this instance can convert the specified object type; otherwise, <c>false</c>.
+        /// </returns>
+        public override bool CanConvert(Type objectType)
+        {
+            return objectType == typeof(DateTime)
+                || objectType == typeof(DateTime?);
+        }
+
+        /// <summary>
+        /// Convert the input value to a value to be serialzied
+        /// </summary>
+        /// <param name="value">The input value to be converted before serialziation</param>
+        /// <returns>A new instance of TResult that is to be serialzied</returns>
+        protected override double? Convert(DateTime? value)
+        {
+            if (value == null)
+            {
+                return null;
+            }
+
+            return (value.Value - UnixEpoch).TotalSeconds;
+        }
+
+        /// <summary>
+        /// Converts the input value to be deserialized
+        /// </summary>
+        /// <param name="value">The deserialized value that needs to be converted to T</param>
+        /// <returns>The converted value</returns>
+        protected override DateTime? Convert(double? value)
+        {
+            if (value == null)
+            {
+                return null;
+            }
+
+            return UnixEpoch.AddSeconds(value.Value);
+        }
+    }
+}