Gaufrette\Adapter\Ftp::exists PHP Method

    public function exists($key)
    {
        $this->ensureDirectoryExists($this->directory, $this->create);
        $file = $this->computePath($key);
        $lines = ftp_rawlist($this->getConnection(), '-al ' . \Gaufrette\Util\Path::dirname($file));
        if (false === $lines) {
            return false;
        }
        $pattern = '{(?<!->) ' . preg_quote(basename($file)) . '( -> |$)}m';
        foreach ($lines as $line) {
            if (preg_match($pattern, $line)) {
                return true;
            }
        }
        return false;
    }