querySelectorAsync

query-selector-async.js

function querySelectorAsync(selector, ttl, root) {
  return new Promise((resolve, reject) => {
    let interval, timeout
    ttl = ttl || 10000
    root = root || document

    try {
      timeout = setTimeout(() => {
        clearInterval(interval)
        throw new Error(`Unable to find element with selector "${selector}"!`)
      }, ttl)

      interval = setInterval(() => {
        const el = root.querySelector(selector)

        if (!el) {
          return
        }

        clearTimeout(timeout)
        clearInterval(interval)
        return resolve(el)
      }, 10)
    } catch (e) {
      clearTimeout(timeout)
      clearInterval(interval)
      return reject(e)
    }
  })
}