如何允许用户在rails应用程序中上传到我的google drive，然后在应用程序中为他们提供google文档的预览链接？

gem 'google-api-client'
gem 'google_drive'

# config/routes.rb
Rails.application.routes.draw do
  get '/auth/google_drive/callback', to: 'google_drive#callback'
  post '/upload', to: 'google_drive#upload'
end

# app/controllers/google_drive_controller.rb
class GoogleDriveController < ApplicationController
  def callback
    # 处理Google Drive授权回调
    client = Google::APIClient.new
    client.authorization.code = params[:code]
    client.authorization.fetch_access_token!
    session[:access_token] = client.authorization.access_token
    redirect_to '/upload'
  end

  def upload
    # 上传文件到Google Drive
    client = Google::APIClient.new
    client.authorization.access_token = session[:access_token]
    drive = client.discovered_api('drive', 'v3')

    file = drive.files.create(
      body: {
        name: params[:file].original_filename,
        parents: ['root']
      },
      media: {
        body: params[:file].tempfile,
        mimeType: params[:file].content_type
      },
      fields: 'id'
    )

    @preview_link = "https://drive.google.com/file/d/#{file.id}/preview"
  end
end