ActiveStorage to upload large base64 encoded string?

Question

If I have an image that was edited/generated using JavaScript on the client (for example, a cropped photo or the result of a canvas drawing), is there a way to upload it using ActiveStorage?

It would typically be a large string containing "<img src='data:image/jpeg;base64,...=='>" that is stored in a JavaScript variable, not a file.

Answer 1

In addition to Diego Carrion's answer

I did like this.

class Booking < ApplicationRecord
  ...
  has_one_attached :signature
  ...

module Api
  module V1
    class BookingsController < Api::V1::ApiController
    ...
    
      def confirm_hire_details
        booking = current_user.bookings.find(params[:id])

        if booking.update(booking_params.merge(
          {
            signature: signature_decoded
          }
        ))
          ...
        else
          ...
        end
      end

      private

      def signature_decoded
        decoded_data = Base64.decode64(params[:signature].split(',')[1])
        {
          io:           StringIO.new(decoded_data),
          content_type: 'image/jpeg',
          filename:     "signature-#{Time.current.to_i}.jpg"
        }
      end

Answer 2

I did it without the gem.

          Model.create!(
            product: product,
            attachment: { 
              io: StringIO.new(Base64.decode64(params[:product][:base_64_image].split(',')[1])),
              content_type: 'image/jpeg',
              filename: 'image.jpeg'
            }
          )