Class MaybeScalarValueJsonConverter<TValue, TPrimitive>

Namespace

Trellis.Asp.Validation

Assembly

Trellis.Asp.dll

A JSON converter for Maybe<T> properties where TValue implements IScalarValue<TSelf, TPrimitive>.

public sealed class MaybeScalarValueJsonConverter<TValue, TPrimitive> : ScalarValueJsonConverterBase<Maybe<TValue>, TValue, TPrimitive> where TValue : class, IScalarValue<TValue, TPrimitive> where TPrimitive : IComparable

Type Parameters

TValue

The scalar value object type.

TPrimitive

The underlying primitive type.

Inheritance

object

JsonConverter

JsonConverter<Maybe<TValue>>

ScalarValueJsonConverterBase<Maybe<TValue>, TValue, TPrimitive>

MaybeScalarValueJsonConverter<TValue, TPrimitive>

Inherited Members

ScalarValueJsonConverterBase<Maybe<TValue>, TValue, TPrimitive>.HandleNull

ScalarValueJsonConverterBase<Maybe<TValue>, TValue, TPrimitive>.Read(ref Utf8JsonReader, Type, JsonSerializerOptions)

JsonConverter<Maybe<TValue>>.CanConvert(Type)

JsonConverter<Maybe<TValue>>.Read(ref Utf8JsonReader, Type, JsonSerializerOptions)

JsonConverter<Maybe<TValue>>.ReadAsPropertyName(ref Utf8JsonReader, Type, JsonSerializerOptions)

JsonConverter<Maybe<TValue>>.WriteAsPropertyName(Utf8JsonWriter, Maybe<TValue>, JsonSerializerOptions)

JsonConverter<Maybe<TValue>>.HandleNull

JsonConverter<Maybe<TValue>>.Type

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Extension Methods

MaybeExtensions.AsMaybe<T>(T)

MaybeExtensions.ToResult<TValue>(TValue)

NullableExtensions.ToResult<T>(T?, Func<Error>)

NullableExtensions.ToResult<T>(T?, Error)

AggregateTestMutator.ClearMaybeField<TEntity, TValue>(TEntity, Expression<Func<TEntity, Maybe<TValue>>>)

AggregateTestMutator.SetMaybeField<TEntity, TValue>(TEntity, Expression<Func<TEntity, Maybe<TValue>>>, TValue?)

Examples

public record RegisterUserDto
{
    public EmailAddress Email { get; init; } = null!;       // required
    public Maybe<FirstName> FirstName { get; init; }  // optional — null = None
}

Remarks

This converter enables DTOs to use Maybe<T> for optional value object properties:

• null JSON value → Maybe.None<TValue>() — no error, value was not provided
• Valid JSON value → Maybe.From(validated) — value provided and valid
• Invalid JSON value → validation error collected, continues deserialization

Unlike ValidatingJsonConverter<TValue, TPrimitive>, this converter treats JSON null as a valid "not provided" signal rather than an error.

Methods

OnNullToken(string)

Returns the result when a JSON null token is read.

protected override Maybe<TValue> OnNullToken(string fieldName)

Parameters

fieldName string

The resolved field name for error reporting.

Returns

Maybe<TValue>

OnValidationFailure()

Returns the result when validation fails.

protected override Maybe<TValue> OnValidationFailure()

Returns

Maybe<TValue>

WrapSuccess(TValue)

Wraps a successfully validated value object into the result type.

protected override Maybe<TValue> WrapSuccess(TValue value)

Parameters

value TValue

Returns

Maybe<TValue>

Write(Utf8JsonWriter, Maybe<TValue>, JsonSerializerOptions)

Writes a specified value as JSON.

[UnconditionalSuppressMessage("Trimming", "IL2026", Justification = "TPrimitive type parameter is preserved by JSON serialization infrastructure")]
[UnconditionalSuppressMessage("AOT", "IL3050", Justification = "JSON serialization of primitive types is compatible with AOT")]
public override void Write(Utf8JsonWriter writer, Maybe<TValue> value, JsonSerializerOptions options)

Parameters

writer Utf8JsonWriter

The writer to write to.

value Maybe<TValue>

The value to convert to JSON.

options JsonSerializerOptions

An object that specifies serialization options to use.