The application could not run because of the following error:
#0 /srv/realestate_www/vendor/mongodb/mongodb/src/Operation/Aggregate.php(219): MongoDB\Driver\Server->executeCommand('realestate', Object(MongoDB\Driver\Command), Object(MongoDB\Driver\ReadPreference)) #1 /srv/realestate_www/vendor/mongodb/mongodb/src/Collection.php(213): MongoDB\Operation\Aggregate->execute(Object(MongoDB\Driver\Server)) #2 /srv/realestate_www/src/classes/RealEstateHelper.php(928): MongoDB\Collection->aggregate(Array) #3 /srv/realestate_www/src/classes/RealEstateHelper.php(316): RealEstateHelper::executeAggregate(Array) #4 /srv/realestate_www/src/routes.php(281): RealEstateHelper::getAllPrices(Array) #5 /srv/realestate_www/src/routes.php(249): generateRegionStatistics(Object(Slim\Container), Object(Slim\Http\Request), Array) #6 [internal function]: Closure->{closure}(Object(Slim\Http\Request), Object(Slim\Http\Response), Array) #7 /srv/realestate_www/vendor/slim/slim/Slim/Handlers/Strategies/RequestResponse.php(41): call_user_func(Object(Closure), Object(Slim\Http\Request), Object(Slim\Http\Response), Array) #8 /srv/realestate_www/vendor/slim/slim/Slim/Route.php(344): Slim\Handlers\Strategies\RequestResponse->__invoke(Object(Closure), Object(Slim\Http\Request), Object(Slim\Http\Response), Array) #9 /srv/realestate_www/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(122): Slim\Route->__invoke(Object(Slim\Http\Request), Object(Slim\Http\Response)) #10 /srv/realestate_www/vendor/slim/slim/Slim/Route.php(316): Slim\Route->callMiddlewareStack(Object(Slim\Http\Request), Object(Slim\Http\Response)) #11 /srv/realestate_www/vendor/slim/slim/Slim/App.php(476): Slim\Route->run(Object(Slim\Http\Request), Object(Slim\Http\Response)) #12 /srv/realestate_www/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(122): Slim\App->__invoke(Object(Slim\Http\Request), Object(Slim\Http\Response)) #13 /srv/realestate_www/vendor/slim/slim/Slim/App.php(370): Slim\App->callMiddlewareStack(Object(Slim\Http\Request), Object(Slim\Http\Response)) #14 /srv/realestate_www/vendor/slim/slim/Slim/App.php(295): Slim\App->process(Object(Slim\Http\Request), Object(Slim\Http\Response)) #15 /srv/realestate_www/public/index.php(52): Slim\App->run() #16 {main}