bigbluebutton-Github/bigbluebutton-html5/imports/api/screenshare/client/bridge/kurento.js

import Auth from '/imports/ui/services/auth';
import BridgeService from './service';
import { fetchWebRTCMappedStunTurnServers, getMappedFallbackStun } from '/imports/utils/fetchStunTurnServers';
import playAndRetry from '/imports/utils/mediaElementPlayRetry';
import logger from '/imports/startup/client/logger';

const SFU_CONFIG = Meteor.settings.public.kurento;
const SFU_URL = SFU_CONFIG.wsUrl;
const CHROME_DEFAULT_EXTENSION_KEY = SFU_CONFIG.chromeDefaultExtensionKey;
const CHROME_CUSTOM_EXTENSION_KEY = SFU_CONFIG.chromeExtensionKey;
const CHROME_SCREENSHARE_SOURCES = SFU_CONFIG.chromeScreenshareSources;
const FIREFOX_SCREENSHARE_SOURCE = SFU_CONFIG.firefoxScreenshareSource;
const SCREENSHARE_VIDEO_TAG = 'screenshareVideo';

const CHROME_EXTENSION_KEY = CHROME_CUSTOM_EXTENSION_KEY === 'KEY' ? CHROME_DEFAULT_EXTENSION_KEY : CHROME_CUSTOM_EXTENSION_KEY;

const getUserId = () => Auth.userID;

const getMeetingId = () => Auth.meetingID;

const getUsername = () => Auth.fullname;

const getSessionToken = () => Auth.sessionToken;

export default class KurentoScreenshareBridge {
  static normalizeError(error = {}) {
    const errorMessage = error.name || error.message || error.reason || 'Unknown error';
    const errorCode = error.code || undefined;
    const errorReason = error.reason || error.id || 'Undefined reason';

    return { errorMessage, errorCode, errorReason };
  }

  static handlePresenterFailure(error, started = false) {
    const normalizedError = KurentoScreenshareBridge.normalizeError(error);
    if (!started) {
      logger.error({
        logCode: 'screenshare_presenter_error_failed_to_connect',
        extraInfo: { ...normalizedError },
      }, `Screenshare presenter failed when trying to start due to ${normalizedError.errorMessage}`);
    } else {
      logger.error({
        logCode: 'screenshare_presenter_error_failed_after_success',
        extraInfo: { ...normalizedError },
      }, `Screenshare presenter failed during working session due to ${normalizedError.errorMessage}`);
    }
    return normalizedError;
  }

  static handleViewerFailure(error, started = false) {
    const normalizedError = KurentoScreenshareBridge.normalizeError(error);
    if (!started) {
      logger.error({
        logCode: 'screenshare_viewer_error_failed_to_connect',
        extraInfo: { ...normalizedError },
      }, `Screenshare viewer failed when trying to start due to ${normalizedError.errorMessage}`);
    } else {
      logger.error({
        logCode: 'screenshare_viewer_error_failed_after_success',
        extraInfo: { ...normalizedError },
      }, `Screenshare viewer failed during working session due to ${normalizedError.errorMessage}`);
    }
    return normalizedError;
  }

  async kurentoWatchVideo() {
    let iceServers = [];
    let started = false;

    try {
      iceServers = await fetchWebRTCMappedStunTurnServers(getSessionToken());
    } catch (error) {
      logger.error({ logCode: 'screenshare_viwer_fetchstunturninfo_error', extraInfo: { error } },
        'Screenshare bridge failed to fetch STUN/TURN info, using default');
      iceServers = getMappedFallbackStun();
    } finally {
      const options = {
        wsUrl: Auth.authenticateURL(SFU_URL),
        iceServers,
        logger,
        userName: getUsername(),
      };

      const screenshareTag = document.getElementById(SCREENSHARE_VIDEO_TAG);

      const playElement = () => {
        const mediaTagPlayed = () => {
          logger.info({
            logCode: 'screenshare_viewer_media_play_success',
          }, 'Screenshare viewer media played successfully');
        };
        if (screenshareTag.paused) {
          // Tag isn't playing yet. Play it.
          screenshareTag.play()
            .then(mediaTagPlayed)
            .catch((error) => {
              // NotAllowedError equals autoplay issues, fire autoplay handling event.
              // This will be handled in the screenshare react component.
              if (error.name === 'NotAllowedError') {
                logger.error({
                  logCode: 'screenshare_viewer_error_autoplay',
                  extraInfo: { errorName: error.name },
                }, 'Screenshare viewer play failed due to autoplay error');
                const tagFailedEvent = new CustomEvent('screensharePlayFailed',
                  { detail: { mediaElement: screenshareTag } });
                window.dispatchEvent(tagFailedEvent);
              } else {
                // Tag failed for reasons other than autoplay. Log the error and
                // try playing again a few times until it works or fails for good
                const played = playAndRetry(screenshareTag);
                if (!played) {
                  logger.error({
                    logCode: 'screenshare_viewer_error_media_play_failed',
                    extraInfo: { errorName: error.name },
                  }, `Screenshare viewer media play failed due to ${error.name}`);
                } else {
                  mediaTagPlayed();
                }
              }
            });
        } else {
          // Media tag is already playing, so log a success. This is really a
          // logging fallback for a case that shouldn't happen. But if it does
          // (ie someone re-enables the autoPlay prop in the element), then it
          // means the stream is playing properly and it'll be logged.
          mediaTagPlayed();
        }
      };

      const onFail = (error) => {
        KurentoScreenshareBridge.handleViewerFailure(error, started);
      };

      // Callback for the kurento-extension.js script. It's called when the whole
      // negotiation with SFU is successful. This will load the stream into the
      // screenshare media element and play it manually.
      const onSuccess = () => {
        started = true;
        const { webRtcPeer } = window.kurentoManager.kurentoVideo;
        if (webRtcPeer) {
          const stream = webRtcPeer.getRemoteStream();
          screenshareTag.muted = true;
          screenshareTag.pause();
          screenshareTag.srcObject = stream;
          playElement();
        }
      };

      window.kurentoWatchVideo(
        SCREENSHARE_VIDEO_TAG,
        BridgeService.getConferenceBridge(),
        getUserId(),
        getMeetingId(),
        onFail,
        onSuccess,
        options,
      );
    }
  }

  kurentoExitVideo() {
    window.kurentoExitVideo();
  }

  async kurentoShareScreen(onFail) {
    let iceServers = [];
    try {
      iceServers = await fetchWebRTCMappedStunTurnServers(getSessionToken());
    } catch (error) {
      logger.error({ logCode: 'screenshare_presenter_fetchstunturninfo_error' },
        'Screenshare bridge failed to fetch STUN/TURN info, using default');
      iceServers = getMappedFallbackStun();
    } finally {
      const options = {
        wsUrl: Auth.authenticateURL(SFU_URL),
        chromeExtension: CHROME_EXTENSION_KEY,
        chromeScreenshareSources: CHROME_SCREENSHARE_SOURCES,
        firefoxScreenshareSource: FIREFOX_SCREENSHARE_SOURCE,
        iceServers,
        logger,
        userName: getUsername(),
      };

      let started = false;

      const failureCallback = (error) => {
        const normalizedError = KurentoScreenshareBridge.handlePresenterFailure(error, started);
        onFail(normalizedError);
      };

      const successCallback = () => {
        started = true;
        logger.info({
          logCode: 'screenshare_presenter_start_success',
        }, 'Screenshare presenter started succesfully');
      };

      window.kurentoShareScreen(
        SCREENSHARE_VIDEO_TAG,
        BridgeService.getConferenceBridge(),
        getUserId(),
        getMeetingId(),
        failureCallback,
        successCallback,
        options,
      );
    }
  }

  kurentoExitScreenShare() {
    window.kurentoExitScreenShare();
  }
}