title: Running browsermob with selenium grid on docker
body: <p>I am using the python client for browsermob to record traffic of my selenium tests. Selenium grid is in a docker container with images for chrome and firefox. I cant seem to configure the docker images properly to connect to the proxy and the grid.
  Here is the code that I use to create the proxy and the remote web driver:</p>
  
  <pre><code>server = browsermobproxy.Server('mylocalpathtobrowsermobbin')
  server.start()
  proxy = server.create_proxy()
  proxy.new_har()
  driver = webdriver.Remote(
                  command_executor='http://127.0.0.1:4444/wd/hub',
                  desired_capabilities={
                      'browserName': 'chrome',
                      'chromeOptions': {
                          'args': ["--proxy-server={}".format(proxy.proxy)]}
                      })
  </code></pre>
  
  <p>And this is my docker-compose file:</p>
  
  <pre>
  hub:
    image: selenium/hub
    ports:
       - "4444:4444"
  chrome:
    image: selenium/node-chrome-debug
    volumes:
      - /dev/shm:/dev/shm
    links:
      - hub
    ports:
      - "5900:5900"</pre>
  
  <p>I am new to docker, I understand that I need to expose the port that the proxy uses to connect but I cannot get it working. Any help is appreciated, thanks!</p>