add root allow login attribute

src/main/java/com/keymobile/proxy/conf/RESTAuthenticationSuccessHandler.java

 package com.keymobile.proxy.conf;
 
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.security.web.authentication.SimpleUrlAuthenticationSuccessHandler;
 import org.springframework.stereotype.Component;
 
+import com.keymobile.proxy.api.Constants;
+
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 import java.io.PrintWriter;
+import java.util.HashMap;
+import java.util.Map;
 
 @Component
 public class RESTAuthenticationSuccessHandler extends SimpleUrlAuthenticationSuccessHandler {
 	
+	@Value("${root.allowLogin:true}")
+	private boolean rootAllowLogin = true;
+
     @Override
     public void onAuthenticationSuccess(HttpServletRequest request, HttpServletResponse response,
                                         Authentication authentication) throws IOException, ServletException {
         clearAuthenticationAttributes(request);
+        String returnStatus = "ok";
+        //check if allow root login
         
+        UserDetails userDetails = (UserDetails) authentication.getPrincipal();
+        String userNameWithIdAttached = userDetails.getUsername();
+        if (userNameWithIdAttached.split(":")[0].equalsIgnoreCase("root")
+        		&& !rootAllowLogin) 
+        	returnStatus = "root not allow login";
         PrintWriter writer = response.getWriter();
-        writer.write("ok");
+        writer.write(returnStatus);
         writer.flush();
         writer.close();
     }