Symfony\Component\HttpFoundation\Request::getClientIps PHP Method

    public function getClientIps()
    {
        $clientIps = array();
        $ip = $this->server->get('REMOTE_ADDR');

        if (!$this->isFromTrustedProxy()) {
            return array($ip);
        }

        $hasTrustedForwardedHeader = self::$trustedHeaders[self::HEADER_FORWARDED] && $this->headers->has(self::$trustedHeaders[self::HEADER_FORWARDED]);
        $hasTrustedClientIpHeader = self::$trustedHeaders[self::HEADER_CLIENT_IP] && $this->headers->has(self::$trustedHeaders[self::HEADER_CLIENT_IP]);

        if ($hasTrustedForwardedHeader) {
            $forwardedHeader = $this->headers->get(self::$trustedHeaders[self::HEADER_FORWARDED]);
            preg_match_all('{(for)=("?\[?)([a-z0-9\.:_\-/]*)}', $forwardedHeader, $matches);
            $forwardedClientIps = $matches[3];

            $forwardedClientIps = $this->normalizeAndFilterClientIps($forwardedClientIps, $ip);
            $clientIps = $forwardedClientIps;
        }

        if ($hasTrustedClientIpHeader) {
            $xForwardedForClientIps = array_map('trim', explode(',', $this->headers->get(self::$trustedHeaders[self::HEADER_CLIENT_IP])));

            $xForwardedForClientIps = $this->normalizeAndFilterClientIps($xForwardedForClientIps, $ip);
            $clientIps = $xForwardedForClientIps;
        }

        if ($hasTrustedForwardedHeader && $hasTrustedClientIpHeader && $forwardedClientIps !== $xForwardedForClientIps) {
            if (!$this->isClientIpsValid) {
                return array('0.0.0.0');
            }
            $this->isClientIpsValid = false;

            throw new ConflictingHeadersException('The request has both a trusted Forwarded header and a trusted Client IP header, conflicting with each other with regards to the originating IP addresses of the request. This is the result of a misconfiguration. You should either configure your proxy only to send one of these headers, or configure your project to distrust one of them.');
        }

        if (!$hasTrustedForwardedHeader && !$hasTrustedClientIpHeader) {
            return $this->normalizeAndFilterClientIps(array(), $ip);
        }

        return $clientIps;
    }

 /**
  * @param Request|\Symfony\Component\HttpFoundation\Request $request
  *
  * @return array
  */
 protected function buildBasicEntry($request)
 {
     return ['api_key' => $request->query->get('api_key', $request->headers->get(ManagedDefaults::DF_API_KEY)), 'content_type' => $request->getContentType(), 'content_length' => (int) $request->headers->get('Content-Length', 0), 'dfe' => [], 'host' => $request->getHost(), 'method' => $request->getMethod(), 'path_info' => $request->getPathInfo(), 'path_translated' => $request->server->get('PATH_TRANSLATED'), 'query' => $request->query->all() ?: [], 'request_timestamp' => (double) $request->server->get('REQUEST_TIME_FLOAT', microtime(true)), 'source_ip' => $request->getClientIps(), 'user_agent' => $request->headers->get('user-agent', 'None')];
 }