RocketChat/Rocket.Chat

import { api } from '@rocket.chat/core-services';
import { Logger } from '@rocket.chat/logger';
import { MongoInternals } from 'meteor/mongo';

import { metrics } from '../../app/metrics/server/lib/metrics';
import { DatabaseWatcher } from '../database/DatabaseWatcher';
import { db } from '../database/utils';
import { SystemLogger } from '../lib/logger/system';
import { initWatchers } from '../modules/watchers/watchers.module';

const { mongo } = MongoInternals.defaultRemoteCollectionDriver();

const watcher = new DatabaseWatcher({ db, _oplogHandle: (mongo as any)._oplogHandle, metrics, logger: Logger });

initWatchers(watcher, api.broadcastLocal.bind(api));

watcher.watch().catch((err: Error) => {
    SystemLogger.fatal(err, 'Fatal error occurred when watching database');
    process.exit(1);
});

setInterval(function _checkDatabaseWatcher() {
    if (watcher.isLastDocDelayed()) {
        SystemLogger.error('No real time data received recently');
    }
}, 20000);

export function isLastDocDelayed(): boolean {
    return watcher.isLastDocDelayed();
}