This will recognize `/photos/1/preview` with GET, and route to the `preview` action of `PhotosController`, with the resource id value passed in `params[:id]`. It will also create the `preview_photo_url` and `preview_photo_path` helpers.
Within the block of member routes, each route name specifies the HTTP verb
Within the block of member routes, each route name specifies the HTTP verb that
will be recognized. You can use `get`, `patch`, `put`, `post`, or `delete` here
. If you don't have multiple `member` routes, you can also pass `:on` to a
