Custom Content-Type negotiation issues

[k0ality]

I want to use custom Content-Type in Format, DefaultFormat, Input Body, Output. It's pure json, but I'm restricted from "application/json", "json" types.

When I specify my custom type in Input Body struct with "contentType" tag I get next results:

• HTTP 415 when I send no "Content-Type" header in request
• crash if I add "Content-Type" header in request

Here's a runnable playground example: https://go.dev/play/p/FWy4_38Rh9z

[giraffesyo]

@k0ality I was able to achieve this in my app:

package routes

import (
	"context"
	"net/http"

	"github.com/danielgtaylor/huma/v2"
	"github.com/parallelworks/core/packages/go/ingress/internal/auth"
)

// WhoAmIOutput represents the whoami operation response.
type WhoAmIOutput struct {
	ContentType string `header:"Content-Type"`
	Body        []byte `example:"user:jakethayne" doc:"The subject of the request, typically a user or the subject of the token."`
}

func RegisterRoutes(api huma.API) {
	huma.Register(api, huma.Operation{
		OperationID: "whoami",
		Method:      http.MethodGet,
		Path:        "/api/auth/whoami",
		Summary:     "Identify the current user",
		Description: "Returns the currently authenticated subject.",
		Tags:        []string{"Authentication"},
	}, func(ctx context.Context, input *struct{}) (*WhoAmIOutput, error) {
		resp := &WhoAmIOutput{}

		// get the subject from the context
		subject := auth.GetSubject(ctx)

		resp.Body = []byte(subject)
		resp.ContentType = "text/plain"
		return resp, nil
	})

}

[richard-hunter-hpe]

@danielgtaylor will merging #926 fix this? I've tested the change against a custom contentType and it seems to work.

[wolveix]

Hey @k0ality! Thanks for opening this, and sorry it's taken a while to be reviewed. I'm pleased to say that this has been fixed in #964, which will be included in our next release :)

@giraffesyo while that is a solution, it stops the real content type being visible in the generated OpenAPI documentation.

@richard-hunter-hpe that PR helps, but doesn't address both reported issues.