private function getTemplate($format)
    {
        $filepath = sprintf('%s/%s.svg', $this->templatesDirectory, $format);

        if (!file_exists($filepath)) {
            throw new \InvalidArgumentException(sprintf('No template for format %s', $format));
        }

        return file_get_contents($filepath);
    }
private function getTemplate($format)
    {
        $filepath = sprintf('%s/%s.svg', $this->templatesDirectory, $format);

        if (!file_exists($filepath)) {
            throw new \InvalidArgumentException(sprintf('No template for format %s', $format));
        }

        return file_get_contents($filepath);
    }
@param $format

@return string SVG content of the template