@architect/functions/src/http/session/providers/_get-idx.js

Runtime utility library for Functional Web Apps (FWAs) built with Architect (https://arc.codes)

// Takes a client cookie string and finds the last _idx key/value
module.exports = function getIdx (cookie = '') {
  let cookies = cookie
    .split(';')
    .map(c => c.trim())
    .filter(Boolean)
  let session = cookies.reverse().find(c => c.startsWith('_idx='))
  return session || ''
}