[Notice] Preflight with no origin will return OPTIONS 404

[fghpdf]

Now you can see there is no [Origin] in my OPTIONS Request

And At Here

cors/config.go

Lines 58 to 62 in 5f50d4f

	origin := c.Request.Header.Get("Origin")
	if len(origin) == 0 {
	// request is not a CORS request
	return
	}

The code will return and do nothing. Will Not Return Headers.

So If you not define OPTIONS Router, you will get 404 immediately.

[jub0bs]

I'm not sure what behaviour you're expecting but, by definition, a preflight request always contains an Origin header.