Running Karate UI tests with "driverTarget" in GitLab CI

Question

I would like to run Karate UI tests using the driverTarget options to test my Java Play app which is running locally during the same job with sbt run.

I have a simple assertion to check for a property but whenever the tests runs I keep getting "description":"TypeError: Cannot read property 'getAttribute' of null This is my karate-config.js:

if (env === 'ci') {
karate.log('using environment:', env);
karate.configure('driverTarget',
    {
        docker: 'justinribeiro/chrome-headless',
        showDriverLog: true
    });
}

This is my test scenario:

Scenario: test 1: some test
Given driver 'http://localhost:9000'
* waitUntil("document.readyState == 'complete'")
* match attribute('some selector', 'some attribute') == 'something'

My guess is that because justinribeiro/chrome-headless is running in its own container, localhost:9000 is different in the container compared to what's running outside of it.

Is there any workaround for this? thanks