Swagger doesn't show int? as nullable

Question

If I have a property:

public int? Test { get; set; }

The correspoding swagger defination is:

test    integer($int32)
        nullable: true

However, when I add [Required] attribute to it:

[Required]
public int? Test { get; set; }

My swagger defination is:

test*   integer($int32)

Why is it no longer nullable?

Answer 1

The [Reqiured] attribute you are using forces the value, to not be null.

According to the documentation:

The RequiredAttribute attribute specifies that when a field on a form is validated, the field must contain a value. A validation exception is raised if the property is null, contains an empty string (""), or contains only white-space characters.