samplify-swagger

configuration.cs

services.AddSwaggerGen(o =>
{
		o.SchemaFilter<SampleFilter>();
		// ...
})

dto.cs

[HasCustomSample]
public class OneRequest
{
	public int I { get; set; }
	public string S { get; set; }
	public bool B { get; set; }
	public decimal N { get; set; }
	public InputDto D { get; set; }
}

public class InputDto
{
	[SampleValue(42)]
	public int I { get; set; }
	[SampleValue("meaningful")]
	public string S { get; set; }
	[SampleValues("a", "b")]
	public string[] A { get; set; }
}

SampleFilter.cs

internal class SampleFilter : ISchemaFilter
{
	public void Apply(Schema model, SchemaFilterContext context)
	{
		var attribute = context.SystemType.GetCustomAttribute<HasCustomSampleAttribute>();
		if (attribute != null)
		{
			model.Example = attribute.BuildExample(context.SystemType);
		}
	}
}

SampleValue.cs

[AttributeUsage(AttributeTargets.Property, Inherited = false, AllowMultiple = false)]
public sealed class SampleValueAttribute : Attribute
{
	public SampleValueAttribute(object value)
	{
		Value = value;
	}

	public object Value { get; }

	private object AssignableValue(PropertyInfo property)
	{
		object assignableValue = Value;

		if (Value != null && !property.PropertyType.IsAssignableFrom(Value.GetType()))
		{
			assignableValue = Convert.ChangeType(Value, property.PropertyType);
		}
		return assignableValue;
	}

	public class SpecimenBuilder : ISpecimenBuilder
	{
		public object Create(object request, ISpecimenContext context)
		{
			object result = new NoSpecimen();
			PropertyInfo property = request as PropertyInfo;
			if (property != null)
			{
				var attribute = property.GetCustomAttribute<SampleValueAttribute>();
				if (attribute != null)
				{
					result = attribute.AssignableValue(property);
				}
			}
			return result;
		}
	}
}