How to extract IP Address in Spring MVC Controller get call?

Question

The solution is

@RequestMapping(value = "processing", method = RequestMethod.GET)
public @ResponseBody ProcessResponse processData(@RequestParam("workflow") final String workflow,
    @RequestParam("conf") final String value, @RequestParam("dc") final String dc, HttpServletRequest request) {

        System.out.println(workflow);
        System.out.println(value);
        System.out.println(dc);
        System.out.println(request.getRemoteAddr());
        // some other code
    }

Add HttpServletRequest request to your method definition and then use the Servlet API

Spring Documentation here said in

15.3.2.3 Supported handler method arguments and return types

Handler methods that are annotated with @RequestMapping can have very flexible signatures.
Most of them can be used in arbitrary order (see below for more details).

Request or response objects (Servlet API). Choose any specific request or response type,
for example ServletRequest or HttpServletRequest

I am late here, but this might help someone looking for the answer. Typically servletRequest.getRemoteAddr() works.

In many cases your application users might be accessing your web server via a proxy server or maybe your application is behind a load balancer.

So you should access the X-Forwarded-For http header in such a case to get the user's IP address.

e.g. String ipAddress = request.getHeader("X-FORWARDED-FOR");

Hope this helps.

I use such method to do this

public class HttpReqRespUtils {

    private static final String[] IP_HEADER_CANDIDATES = {
        "X-Forwarded-For",
        "Proxy-Client-IP",
        "WL-Proxy-Client-IP",
        "HTTP_X_FORWARDED_FOR",
        "HTTP_X_FORWARDED",
        "HTTP_X_CLUSTER_CLIENT_IP",
        "HTTP_CLIENT_IP",
        "HTTP_FORWARDED_FOR",
        "HTTP_FORWARDED",
        "HTTP_VIA",
        "REMOTE_ADDR"
    };

    public static String getClientIpAddressIfServletRequestExist() {

        if (RequestContextHolder.getRequestAttributes() == null) {
            return "0.0.0.0";
        }

        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
        for (String header: IP_HEADER_CANDIDATES) {
            String ipList = request.getHeader(header);
            if (ipList != null && ipList.length() != 0 && !"unknown".equalsIgnoreCase(ipList)) {
                String ip = ipList.split(",")[0];
                return ip;
            }
        }

        return request.getRemoteAddr();
    }
}

You can get the IP address statically from the RequestContextHolder as below :

HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes())
        .getRequest();

String ip = request.getRemoteAddr();

Below is the Spring way, with autowired request bean in @Controller class:

@Autowired 
private HttpServletRequest request;

System.out.println(request.getRemoteHost());

Put this method in your BaseController:

@SuppressWarnings("ConstantConditions")
protected String fetchClientIpAddr() {
    HttpServletRequest request = ((ServletRequestAttributes) (RequestContextHolder.getRequestAttributes())).getRequest();
    String ip = Optional.ofNullable(request.getHeader("X-FORWARDED-FOR")).orElse(request.getRemoteAddr());
    if (ip.equals("0:0:0:0:0:0:0:1")) ip = "127.0.0.1";
    Assert.isTrue(ip.chars().filter($ -> $ == '.').count() == 3, "Illegal IP: " + ip);
    return ip;
}