Setting path to local GhostDriver, on PhantomJS, using test from Selenium WebdriverJs where that value is passed in the Capabilities section

Question

The objective is to hit a local version of GhostDriver, by leveraging the configuration of its path, that the Capabilities allow us to set: https://github.com/detro/ghostdriver/blob/master/README.md#what-extra-webdriver-capabilities-ghostdriver-offers

When running a test with Selenium webdriverjs like the trivial example:

var webdriver = require('selenium-webdriver');

var capabilities = webdriver.Capabilities.phantomjs();
capabilities.set('phantomjs.ghostdriver.path',
    '/Users/xyz/ghostdriver-master/src/main.js');

var driver = new webdriver.Builder().
    withCapabilities(capabilities).
    build();

driver.get('http://www.google.com');
driver.findElement(webdriver.By.name('q')).sendKeys('webdriver');
driver.findElement(webdriver.By.name('btnG')).click();
driver.wait(function() {
    return driver.getTitle().then(function(title) {
        console.log(title);
    });
}, 1000);

driver.quit();

I am not able to hit my local version of GhostDriver. It just hits the default version which is baked into phantomjs.

However, if I use WebdriverIO using the same Capability definition:

var webdriverio = require('webdriverio');
var options = {
    desiredCapabilities: {
        'browserName': 'phantomjs',
        'phantomjs.ghostdriver.path':     '/Users/xyz/ghostdriver-master/src/main.js'
    },
    port: 4444
};
webdriverio
    .remote(options)
    .init()
    .url('http://www.google.com')
    .title(function(err, res) {
        console.log(res.value);
    })
    .end();

I am able to hit my local version of GhostDriver.

After looking at the documentation here: https://github.com/detro/ghostdriver/blob/master/README.md#what-extra-webdriver-capabilities-ghostdriver-offers

and other pages with similar issues, I was not able to find anything that worked.

versions used:

• selenium-server-standalone v2.51.0
• selenium-webdriver v2.48.2
• webdriverio v4.0.2
• phantomjs v2.1.1

Has anybody got an idea of how to get this working?