Merge pull request #4033 from crobibero/empty-string-nullable-number

Readd nullable number converters

MediaBrowser.Common/Json/Converters/JsonNullableStructConverter.cs

@@ -0,0 +1,44 @@
+using System;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace MediaBrowser.Common.Json.Converters
+{
+    /// <summary>
+    /// Converts a nullable struct or value to/from JSON.
+    /// Required - some clients send an empty string.
+    /// </summary>
+    /// <typeparam name="T">The struct type.</typeparam>
+    public class JsonNullableStructConverter<T> : JsonConverter<T?>
+        where T : struct
+    {
+        private readonly JsonConverter<T?> _baseJsonConverter;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="JsonNullableStructConverter{T}"/> class.
+        /// </summary>
+        /// <param name="baseJsonConverter">The base json converter.</param>
+        public JsonNullableStructConverter(JsonConverter<T?> baseJsonConverter)
+        {
+            _baseJsonConverter = baseJsonConverter;
+        }
+
+        /// <inheritdoc />
+        public override T? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+        {
+            // Handle empty string.
+            if (reader.TokenType == JsonTokenType.String && ((reader.HasValueSequence && reader.ValueSequence.IsEmpty) || reader.ValueSpan.IsEmpty))
+            {
+                return null;
+            }
+
+            return _baseJsonConverter.Read(ref reader, typeToConvert, options);
+        }
+
+        /// <inheritdoc />
+        public override void Write(Utf8JsonWriter writer, T? value, JsonSerializerOptions options)
+        {
+            _baseJsonConverter.Write(writer, value, options);
+        }
+    }
+}

MediaBrowser.Common/Json/JsonDefaults.cs

@@ -29,8 +29,14 @@ namespace MediaBrowser.Common.Json
                 NumberHandling = JsonNumberHandling.AllowReadingFromString
             };
 
+            // Get built-in converters for fallback converting.
+            var baseNullableInt32Converter = (JsonConverter<int?>)options.GetConverter(typeof(int?));
+            var baseNullableInt64Converter = (JsonConverter<long?>)options.GetConverter(typeof(long?));
+
             options.Converters.Add(new JsonGuidConverter());
             options.Converters.Add(new JsonStringEnumConverter());
+            options.Converters.Add(new JsonNullableStructConverter<int>(baseNullableInt32Converter));
+            options.Converters.Add(new JsonNullableStructConverter<long>(baseNullableInt64Converter));
 
             return options;
         }