Function maybeTrackImpression

src/impression.js:58–100

(win)

 * @param {!Window} win
 */
export function maybeTrackImpression(win) {
  const deferred = new Deferred();
  const {promise, resolve: resolveImpression} = deferred;

  trackImpressionPromise = Services.timerFor(win)
    .timeoutPromise(TIMEOUT_VALUE, promise, 'TrackImpressionPromise timeout')
    .catch((error) => {
      dev().warn('IMPRESSION', error);
    });

  const viewer = Services.viewerForDoc(win.document.documentElement);
  const isTrustedViewerPromise = viewer.isTrustedViewer();
  const isTrustedReferrerPromise = viewer
    .getReferrerUrl()
    .then((referrer) => isTrustedReferrer(referrer));
  Promise.all([isTrustedViewerPromise, isTrustedReferrerPromise]).then(
    (results) => {
      const isTrustedViewer = results[0];
      const isTrustedReferrer = results[1];
      // Enable the feature in the case of trusted viewer,
      // or trusted referrer
      // or with experiment turned on
      if (
        !isTrustedViewer &&
        !isTrustedReferrer &&
        !isExperimentOn(win, 'alp')
      ) {
        resolveImpression();
        return;
      }

      const replaceUrlPromise = handleReplaceUrl(win);
      const clickUrlPromise = handleClickUrl(win);

      Promise.all([replaceUrlPromise, clickUrlPromise]).then(
        () => {
          resolveImpression();
        },
        () => {}
      );
    }
  );
}

/**
 * Signal that impression tracking is not relevant in this environment.