MatthiasMullie\Scrapbook\Adapters\Couchbase::flush PHP Метод

    public function flush()
    {
        // depending on config & client version, flush may not be available
        try {
            /*
             * Flush wasn't always properly implemented[1] in the client, plus
             * it depends on server config[2] to be enabled. Return status has
             * been null in both success & failure cases.
             * Flush is a very pervasive function that's likely not called
             * lightly. Since it's probably more important to know whether or
             * not it succeeded, than having it execute as fast as possible, I'm
             * going to add some calls and test if flush succeeded.
             *
             * 1: https://forums.couchbase.com/t/php-flush-isnt-doing-anything/1886/8
             * 2: http://docs.couchbase.com/admin/admin/CLI/CBcli/cbcli-bucket-flush.html
             */
            $this->client->upsert('cb-flush-tester', '');
            $manager = $this->client->manager();
            if (method_exists($manager, 'flush')) {
                // ext-couchbase >= 2.0.6
                $manager->flush();
            } elseif (method_exists($this->client, 'flush')) {
                // ext-couchbase < 2.0.6
                $this->client->flush();
            } else {
                return false;
            }
        } catch (\CouchbaseException $e) {
            return false;
        }
        try {
            // cleanup in case flush didn't go through; but if it did, we won't
            // be able to remove it and know flush succeeded
            $result = $this->client->remove('cb-flush-tester');
            return (bool) $result->error;
        } catch (\CouchbaseException $e) {
            // exception: "The key does not exist on the server"
            return true;
        }
    }