Function onDocumentFormSubmit_

src/document-submit.js:36–158

(e)

 * @param {!Event} e
 */
export function onDocumentFormSubmit_(e) {
  if (e.defaultPrevented) {
    return;
  }

  const form = dev().assertElement(e.target);
  if (!form || form.tagName != 'FORM') {
    return;
  }

  // amp-form extension will add novalidate to all forms to manually trigger
  // validation. In that case `novalidate` doesn't have the same meaning.
  const isAmpFormMarked = form.classList.contains('i-amphtml-form');
  let shouldValidate;
  if (isAmpFormMarked) {
    shouldValidate = !form.hasAttribute('amp-novalidate');
  } else {
    shouldValidate = !form.hasAttribute('novalidate');
  }

  // Safari does not trigger validation check on submission, hence we
  // trigger it manually. In other browsers this would never execute since
  // the submit event wouldn't be fired if the form is invalid.
  if (shouldValidate && form.checkValidity && !form.checkValidity()) {
    e.preventDefault();
  }

  const inputs = form.elements;
  for (let i = 0; i < inputs.length; i++) {
    userAssert(
      !inputs[i].name || inputs[i].name != SOURCE_ORIGIN_PARAM,
      'Illegal input name, %s found: %s',
      SOURCE_ORIGIN_PARAM,
      inputs[i]
    );
  }

  const action = form.getAttribute('action');
  const actionXhr = form.getAttribute('action-xhr');
  const method = (form.getAttribute('method') || 'GET').toUpperCase();

  if (actionXhr) {
    assertHttpsUrl(actionXhr, form, 'action-xhr');
    userAssert(
      !isProxyOrigin(actionXhr),
      'form action-xhr should not be on AMP CDN: %s',
      form
    );
    checkCorsUrl(actionXhr);
  }
  if (action) {
    assertHttpsUrl(action, form, 'action');
    userAssert(
      !isProxyOrigin(action),
      'form action should not be on AMP CDN: %s',
      form
    );
    checkCorsUrl(action);