windows-updater.js

const rx = require('rx');
const request = require('../request-rx');
const path = require('path');
const fs = require('fs');
const spawn = require('../spawn-rx');
const _ = require('lodash');
const semver = require('semver');
const {is64BitOperatingSystem} = require('../native-interop');

const logger = require('./logger').init(__filename);

// Public: This class handles updates via Squirrel for Windows, basically just
// by spawning a process. Note that this class must method-for-method match
// MacSquirrelUpdater and vice-versa or else we're Gonna Have A Bad Time(tm).
class WindowsSquirrelUpdater {
  // Public: Creates an instance.
  //   options: An {Object} with the following keys:
  //
  //   :version - The version string from {SlackApplication} (i.e. '0.1.2-0f3d3ac')
  constructor(options) {
    this.version = options.version.split('-')[0];

    let updateUrl = is64BitOperatingSystem() ?
      'https://slack-ssb-updates.global.ssl.fastly.net/releases_x64' :
      'https://slack-ssb-updates.global.ssl.fastly.net/releases';

    this.ssbUpdateUrl = options.ssbUpdateUrl || process.env.SLACK_UPDATE_URL || updateUrl;
  }

  // Public: Initiates a check for updates
  //
  // Returns an Observable which produces one of:
  //     true - The update worked, we'll run a new version next execution
  //     false - There were no updates
  //     (OnError) - Something went pear-shaped while checking for updates
  checkForUpdates() {
    logger.info('Starting check for updates');

    // NB: On Windows, request is using some certificate store that marks S3 as
    // invalid. This is hella shady, but the actual update will be done by C#
    // which will use the HTTPS url.
    return request.fetchFileOrUrl(this.ssbUpdateUrl.replace(/^https:/i, 'http:') + "/RELEASES").map((body) => {
      // 81D4BED4FD0FC59C3995D0CC8D8B35301D38851D slack-1.8.1-full.nupkg 60556480
      let versions = _.map(body.split("\n"), (line) => {
        let filename = line.split(/\s+/)[1];
        if (!filename) return null;

        let nameAndVer = filename.substring(0, filename.lastIndexOf('-'));
        let ver = nameAndVer.substring(nameAndVer.lastIndexOf('-') + 1);

        logger.debug(`Found version: ${ver}`);
        return ver;
      });

      let latest = _.reduce(versions, (acc,x) => {
        // NB: At some point we released 0.7.1.1 which causes semver.gt to lose its mind
        if (!semver.valid(x)) return acc;
        logger.debug(`${acc} <=> ${x}`);
        return semver.gt(acc, x) ? acc : x;
      }, this.version);

      logger.info(`Finished manual update, local: ${this.version}, remote: ${latest}`);
      return semver.gt(latest, this.version);
    });
  }

  // Public: Updates the app but keeps the current version running. The new
  // version will not be started until the next execution.
  //
  // Returns an {Observable} signaling completion
  doBackgroundUpdate() {
    return this.spawnUpdateDotExe(['--update', this.ssbUpdateUrl]);
  }

  // Public: Updates the app and restarts it immediately thereafter
  //
  // closeApp - A method that will shutdown the app
  //
  // Returns nothing
  forceUpdateAndRestart(closeApp) {
    this.spawnUpdateDotExe(['--update', this.ssbUpdateUrl])
      .flatMap(() =>  {
        logger.debug("Update succeeded, starting new Slack");

        return this.spawnUpdateDotExe(['--processStartAndWait', 'slack.exe'])
          .takeLast(1)
          .timeout(2 * 1000)
          .catch(rx.Observable.return(false));
      })
      .subscribe(
        () => closeApp(),
        (e) => logger.error(`Failed to force update: ${e.message}`));
  }

  // Private: Maps an Update.exe process into an {Observable}
  //
  // params - Arguments passed to the process
  //
  // Returns an {Observable} with a single value, that is the output of the
  // spawned process
  spawnUpdateDotExe(params) {
    let updateDotExe = path.resolve(path.dirname(process.execPath), '..', 'update.exe');
    if (!fs.statSyncNoException(updateDotExe)) {
      return rx.Observable.return('');
    }

    return spawn(updateDotExe, params);
  }
}

module.exports = WindowsSquirrelUpdater;