phantomas/extensions/waitForSelector/waitForSelector.js

Headless Chromium-based web performance metrics collector and monitoring tool

/**
 * Delays report generation until given CSS selector can be resolved (i.e. given element exists)
 */
"use strict";

module.exports = function (phantomas) {
  // e.g. --wait-for-selector "body.loaded"
  var selector = phantomas.getParam("wait-for-selector");

  if (typeof selector !== "string") {
    return;
  }

  // https://github.com/GoogleChrome/puppeteer/blob/v1.11.0/docs/api.md#framewaitforselectororfunctionortimeout-options-args
  phantomas.log('Will wait for "%s" selector', selector);

  phantomas.on("beforeClose", (page) => {
    phantomas.log('Waiting for "%s"...', selector);

    return page.waitForSelector(selector);
  });
};