fix: better json support for KeyValueUrn

src/Altinn.Urn/src/Altinn.Urn/KeyValueUrn.cs

@@ -1,6 +1,8 @@
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Numerics;
+using System.Text.Json;
+using System.Text.Json.Serialization;
 
 namespace Altinn.Urn;
 
@@ -12,6 +14,7 @@
 /// To construct a <see cref="KeyValueUrn"/>, you need to know where the prefix ends and the value starts.
 /// </remarks>
 [DebuggerDisplay("{Urn}")]
+[JsonConverter(typeof(JsonConverter))]
 public readonly struct KeyValueUrn
  : IKeyValueUrn
  , IEquatable<KeyValueUrn>
@@ -22,7 +25,7 @@
  /// </summary>
  /// <param name="urn">The original <see cref="IKeyValueUrn"/>.</param>
  /// <returns>A new <see cref="KeyValueUrn"/>.</returns>
  public static KeyValueUrn Create(IKeyValueUrn urn)
  => new(urn.Urn, urn.KeySpan.Length + 1);
 
  /// <summary>
@@ -104,14 +107,14 @@
  public ReadOnlySpan<char> AsSpan() => _urn.AsSpan();
 
  /// <inheritdoc/>
  public bool Equals(KeyValueUrn other)
  {
  return _urn == other._urn
  && _valueIndex == other._valueIndex;
  }
 
  /// <inheritdoc/>
  public string ToString(string? format, IFormatProvider? formatProvider)
  {
  return format.AsSpan() switch
  {
@@ -160,4 +163,18 @@
  /// <inheritdoc/>
  public static bool operator !=(KeyValueUrn left, KeyValueUrn right)
  => !left.Equals(right);
+
+ private sealed class JsonConverter
+ : JsonConverter<KeyValueUrn>
+ {
+ public override KeyValueUrn Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+ {
+ throw new NotSupportedException($"Deserialization of {nameof(KeyValueUrn)} is not supported.");
+ }
+
+ public override void Write(Utf8JsonWriter writer, KeyValueUrn value, JsonSerializerOptions options)
+ {
+ writer.WriteStringValue(value.Urn);
+ }
+ }
 }

src/Altinn.Urn/test/Altinn.Urn.Tests/KeyValueUrnTests.cs

@@ -163,4 +163,23 @@ public void UrnJsonTypeValue_Equality()
  (obj1 == obj2).Should().BeTrue();
  (obj1 != obj2).Should().BeFalse();
  }
+
+ [Fact]
+ public void KeyValueUrn_IsSerializeable()
+ {
+ var sut = KeyValueUrn.Create("urn:example:123", 12);
+ var json = JsonSerializer.Serialize(sut);
+
+ json.Should().Be(@"""urn:example:123""");
+ }
+
+ [Fact]
+ public void KeyValueUrn_Deserialize_ShouldThrow()
+ {
+ var json = @"""urn:example:123""";
+ Action act = () => JsonSerializer.Deserialize<KeyValueUrn>(json);
+
+ act.Should().Throw<NotSupportedException>()
+ .Which.Message.Should().StartWith($"Deserialization of {nameof(KeyValueUrn)} is not supported.");
+ }
 }