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gRPC на отдельном порту

src/Console/Data/BarcodesJsonConverter.cs

@@ -0,0 +1,19 @@
+using System.Text.Json;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+namespace ConsoleApp.Data;
+
+internal static class BarcodesJsonConverter
+{
+    private static readonly JsonSerializerOptions JsonOptions = new();
+
+    public static ValueConverter<List<string>, string> Instance { get; } = new(
+        v => Serialize(v),
+        v => Deserialize(v));
+
+    private static string Serialize(List<string> value) =>
+        JsonSerializer.Serialize(value, JsonOptions);
+
+    private static List<string> Deserialize(string value) =>
+        JsonSerializer.Deserialize<List<string>>(value, JsonOptions) ?? [];
+}