val serve : ?mime_type:string -> ?etag:string -> ?headers:Headers.t -> ( unit -> ( Body.t, [ Status.client_error | Status.server_error ] ) Lwt_result.t ) -> Rock.Handler.t
serve ?mime_type ?etag ?headers read returns a handler that will serve the result of
It is typically used to serve static file by providing a read function, either reading from the local filesystem, or from a remote one such as Amazon S3.
The response will contain an ETag header and a the HTTP code
304 will be returned if the computed ETag matches the one specified in the request.