[Bug]: Optional route parameter gets rendered as required

[sommmen]

Describe the bug

The following endpoint:

    [HttpGet("packing-dashboard")]
    [HttpGet("packing-dashboard/{partner?}")]
    public async Task<IActionResult> GetDashboard([FromRoute] string? partner = default, CancellationToken cancellationToken = default)

Makes the partner value required in the UI:

Ditto for the document:

Expected behavior

The partner variable should be optional.

Actual behavior

Its required.

Steps to reproduce

Paste the sample code above in a controller.

Exception(s) (if any)

No response

Swashbuckle.AspNetCore version

Latest (6.8.0)

.NET Version

net8.0

Anything else?

No response

[martincostello]

Latest

To confirm, is this with 6.8.0?

[sommmen]

Latest

To confirm, is this with 6.8.0?

Did not expect the 2hrs ago release - i will recheck if this issue persists on that version.

[sommmen]

Latest

To confirm, is this with 6.8.0?

Unfortunately the issue remains with 6.8.0.

[jgarciadelanoceda]

This seems to be the expected behaviour:

Swashbuckle.AspNetCore/src/Swashbuckle.AspNetCore.SwaggerGen/SwaggerGenerator/ApiParameterDescriptionExtensions.cs

Lines 34 to 39 in 9f4dacd

	// From the OpenAPI spec:
	// If the parameter location is "path", this property is REQUIRED and its value MUST be true.
	if (apiParameter.IsFromPath())
	{
	return true;
	}

Last PR against this: #2183