InfluxDB\Client::listDatabases PHP Method

    public function listDatabases()
    {
        $result = $this->query(null, 'SHOW DATABASES')->getPoints();
        return $this->pointsToArray($result);
    }

 /**
  * @return bool
  */
 public function exists()
 {
     $databases = $this->client->listDatabases();
     return in_array($this->name, $databases);
 }