utils.js

// Look for a warning on the page and raise it as an error.
async function raiseWarning(page, action, selector) {
  const warning = await page.$('.notification--warning');
  if (!warning) {
    return
  }

  const warningText = await page.evaluate((el) => { return el.textContent }, warning);
  throw `Barclays Error: "${warningText.trim()}" (while ${action} ${selector})`;
}

exports.screenshot = async(page, filename) => {
  await page.screenshot({path: filename, fullPage: true});
}

// Click a link and wait for the navigation state to go to idle.
exports.click = async (page, selector) => {
  try {
    await Promise.all([
      page.waitForNavigation({timeout: 30000}),
      // Executing el.click() within the page context with $eval means we can
      // click invisible links, which simplifies things.
      page.$eval(selector, el => { el.click() }),
    ]);
  } catch (err) {
    raiseWarning(page, 'clicking', selector);

    await exports.screenshot(page, 'error.png');
    throw `Error when clicking ${selector} on URL ${page.url()}: ${err}`;
  }
};

exports.fillField = async (page, key, value) => {
    await page.click(key);
    await page.type(key, value);
}

exports.fillFields = async (page, form) => {
  // Disappointingly, you can't type into multiple fields simultaneously.
  for (let key of Object.keys(form)) {
    await exports.fillField(page, key, form[key]);
  }
};

exports.getAttribute = (page, element, attribute) => {
  return page.evaluate((el, attr) => { return el.getAttribute(attr) }, element, attribute);
};

// Wait for a selector to become visible, and issue a nice error if it doesn't.
exports.wait = async (page, selector) => {
  try {
    await page.waitForSelector(selector, {timeout: 30000});
  } catch (err) {
    raiseWarning(page, 'fetching', selector);

    let screenshotFile = './error.png';
    await exports.screenshot(page, screenshotFile);
    throw `Couldn't find selector "${selector}" on page ${page.url()}. Screenshot saved to ${screenshotFile}.`;
  }
};

exports.cssEsc = (string) => {
  return string.replace(/([\\'"])/g, '\\$1');
};