What's the fluent API counterpart of ComplexTypeAttribute?

[voroninp]

How do I declare type as a complex type with fluent mapping API?

ComplexProperty must be called on the entity, but I just want the same effect as [ComplexType] has.

[ajcvickers]

protected override void ConfigureConventions(ModelConfigurationBuilder configurationBuilder)
{
    configurationBuilder.ComplexProperties<Contact>();
    configurationBuilder.ComplexProperties<Address>();
    configurationBuilder.ComplexProperties<PhoneNumber>();
}

[voroninp]

Thanks.

[voroninp]

@ajcvickers But how do I configure read-only properties mapping then?

public readonly record struct InclusiveDatesRange
{
    public DateOnly Start { get; }
    public DateOnly End { get; }

    public InclusiveDatesRange(DateOnly start, DateOnly end)
    {
        if (end < start)
        {
            throw new ArgumentException($"Start '{start}' cannot be later than end '{end}'.");
        }

        Start = start;
        End = end;
    }
}

It's a readonly struct so properties cannot have private setters.

Currently I configure this for entity:

modelBuilder.Entity<DataActualityPeriod>(b =>
{
    b.HasAlternateKey(e => e.Code);

    b.ComplexProperty(
        e => e.DatesRange,
        b =>
        {
            b.Property(b => b.Start);
            b.Property(b => b.End);
        });
});

But there's no overload of ComplexProperties which lets me configure the mapping.

[voroninp]

@ajcvickers , btw, b.HasAlternateKey(e => new { e.DatesRange.Start, e.DatesRange.End }); this does not work.

Neither works this b.HasIndex(e => new { e.DatesRange.Start, e.DatesRange.End }).IsUnique();

Unable to create a 'DbContext' of type ''. The exception 'The expression 'e => new <>f__AnonymousType0`2(Start = e.DatesRange.Start, End = e.DatesRange.End)' is not a valid member access expression. The expression should represent a simple property or field access: 't => t.MyProperty'. When specifying multiple properties or fields, use an anonymous type: 't => new { t.MyProperty, t.MyField }'. (Parameter 'memberAccessExpression')' was thrown while attempting to create an instance. For the different patterns supported at design time, see https://go.microsoft.com/fwlink/?linkid=851728

And why is it an empty string '' in the message: Unable to create a 'DbContext' of type ''. ?

[voroninp]

And how do I set index on properties of complex type?

[roji]

@voroninp that's #31246.

[voroninp]

@ajcvickers Wait a second. Not planned what? Combining mapping details with configurationBuilder.ComplexProperties<TComplexType>(); ?
I mean this comment