A utility class that extracts the actual IP and port to which your remote executions are being routed to by Grid2

GridInfoExtracter.java

public class GridInfoExtracter{

	private static String[] getHostNameAndPort(String hostName, int port,
			SessionId session) {
		String[] hostAndPort = new String[2];
		String errorMsg = "Failed to acquire remote webdriver node and port info. Root cause: ";

		try {
			HttpHost host = new HttpHost(hostName, port);
			DefaultHttpClient client = new DefaultHttpClient();
			URL sessionURL = new URL("http://" + hostName + ":" + port + "/grid/api/testsession?session=" + session);
			BasicHttpEntityEnclosingRequest r = new BasicHttpEntityEnclosingRequest("POST", sessionURL.toExternalForm());
			HttpResponse response = client.execute(host, r);
			JSONObject object = extractObject(response);
			URL myURL = new URL(object.getString("proxyId"));
			if ((myURL.getHost() != null) && (myURL.getPort() != -1)) {
				hostAndPort[0] = myURL.getHost();
				hostAndPort[1] = Integer.toString(myURL.getPort());
			}
		} catch (Exception e) {
			logger.log(Level.SEVERE, errorMsg, e);
			throw new RuntimeException(errorMsg, e);
		}
		return hostAndPort;
	}

	private static JSONObject extractObject(HttpResponse resp) throws IOException, JSONException {
		BufferedReader rd = new BufferedReader(new InputStreamReader(resp.getEntity().getContent()));
		StringBuffer s = new StringBuffer();
		String line;
		while ((line = rd.readLine()) != null) {
			s.append(line);
		}
		rd.close();
		JSONObject objToReturn = new JSONObject(s.toString());
		return objToReturn;
	}
}

And here's a snippet for Python 2.x, for getting hostname

import json
import urllib2 
from selenium import webdriver
from urlparse import urlparse
driver = webdriver.Remote( command_executor='http://localhost:4444/wd/hub',desired_capabilities={'browserName':'firefox'})
grid_node_extract_url = "http://localhost:4444/grid/api/testsession?session=%s" % driver.session_id
response = urllib2.urlopen(grid_node_extract_url).read()
node_host = urlparse(json.loads(response).get('proxyId')).hostname # use .port for port
print node_host
driver.quit()

For Python 3.x, making the following substitutions should work

import urllib.request
from urllib.parse import urlparse
from __future__ import print_function
response = urllib.request.urlopen(grid_node_extract_url).read()
print(node_host)

Here's the Ruby version (for v1.9+, for older versions, may have to resort to require 'net/http' and use that or something else instead of this REST client to make the HTTP request to get proxy URL with hostname)

#gem install rest-client & selenium as needed
require "selenium-webdriver"
require 'rest-client'
require 'json'
require 'uri'

caps = Selenium::WebDriver::Remote::Capabilities.firefox
driver = Selenium::WebDriver.for(:remote, :url => "http://localhost:4444/wd/hub", :desired_capabilities => caps)
grid_node_extract_url = "http://localhost:4444/grid/api/testsession?session=#{driver.session_id}"
response = RestClient.get grid_node_extract_url 
response = JSON.parse(response)
node_host = URI(response['proxyId']).host # use .port for port
puts node_host
driver.quit

getting lot of compilation error, can you please add the imported package as well, if possible? or are those still valid as this post is 10 years old?

@mdsapon - You should perhaps take a look at this library that I built as a follow up to this gist : https://github.com/RationaleEmotions/talk2grid

@mdsapon - You should perhaps take a look at this library that I built as a follow up to this gist : https://github.com/RationaleEmotions/talk2grid

Thanks a lot, this is amazing and works great with Selenium 3, but didn't work with Selenium 4. Do you have any plan to upgrade? Btw thanks a ton for creating this library

@mdsapon - I haven't yet delved into Grid4 completely. But its definitely on the cards. I didnt take this library so seriously because I didn't see many people even have a want to use it :D

I will work on sorting it out hopefully soon.