Presigned response - options request using uppy

Hi there

was wondering if you folks have faced this issue:

  • I have an s3 bucket.
  • I am uploading files directly to this bucket via uppy.
  • I need to make a preflight request.
  • I want to protect this preflight request so that only authenticated users can hit it.

mount Shrine.presign_endpoint(:cache) => “/s3/params”

# how does one ensure that uppy's options request are also handled?
# the following causes some errors to return
# match "s3/params", to: "presigns#file", via: [:get, :post, :put, :options] # am i doing this right?

# presigns controller
class PresignsController < ApplicationController
  def file
    set_rack_response FileUploader.presign_response(:cache, request.env)


  def set_rack_response((status, headers, body))
    self.status = status
    self.response_body = body

Right now I am getting an error if I am protecting this endpoint using the code that is commented out above - rails is saying i have an invalid authenticity token Was wondering how you folks handle it?

Relevant discussion in github.

Any pointers would be much appreciated.