Issue with enum query parameter with a default value

If a query parameter is of type enum and has a default value, the swagger parameter for default should be appropriately set and required should be set to true.

Here is an example below.

what's happening

(GET "/all/" request
     :description "Return a list of articles."
     :return [(dissoc t/Article :is_html :text)]
     :responses default-responses
     :query-params [{sort :- (describe (s/enum :published_at :last_processed_at) "The sort type. Defaults to published_at.") "published_at"}]
     (return (domain/get-all-articles db (org request) :days 1)))

The sort parameter above can be either published_at or last_processed_at where it defaults to the former.

The JSON output for the route above is:

"parameters": [
  {
    "in": "query",
    "name": "sort",
    "description": "The sort type. Defaults to published_at.",
    "required": false,
    "type": "string",
    "enum": [
      "last_processed_at",
      "published_at"
    ]
  }
]

And the UI renders like this:

expectation

I would expect the select box in the UI to start off with the published_at pre-selected and not allow a nil option.
I would expect the json output to have required set to true and a default value set to published_at.

Thanks for your time!

Start by tracing Swagger parameter generation for the enum query parameter shown in the issue. Check how the default value and required flag are derived, then verify that the generated JSON includes default "published_at" and required true, with no nil option in the UI.