Selenium Grid error on GitLab CI: Error forwarding the new session Empty pool of VM for setup Capabilities

Question

Since documentation on GitLab CI configuration and Selenium is generally poor, I'm asking for help.

Configuration as by interest point:

gitlab.ci.yml:

image: node:7

variables:
  HUB_PORT_4444_TCP_ADDR: "selenium__hub"
  HUB_PORT_4444_TCP_PORT: "4444"

services:
  - selenium/hub:latest
  - selenium/node-phantomjs:latest

stages:
  - test

test:
  stage: test
  before_script:
    - apt-get update
    - apt-get install -y default-jdk default-jre
    - npm install -s -g @angular/[email protected]
    - npm install -s
    - node ./node_modules/protractor/bin/webdriver-manager update
  script:
    - ./node_modules/.bin/protractor protractor.ci.conf.js

protractor.ci.conf.js:

/*global jasmine */
const { SpecReporter } = require('jasmine-spec-reporter');

exports.config = {
  allScriptsTimeout: 11000,
  specs: [
    './e2e/**/*.e2e-spec.ts'
  ],
  capabilities: {
    'browserName': 'phantomjs',
    'phantomjs.binary.path': './node_modules/phantomjs-prebuilt/bin/phantomjs'
  },
  directConnect: false,
  baseUrl: 'http://localhost:4200/',
  framework: 'jasmine',
  jasmineNodeOpts: {
    showColors: true,
    defaultTimeoutInterval: 30000,
    print: function() {}
  },
  beforeLaunch: function() {
    require('ts-node').register({
      project: 'e2e/tsconfig.e2e.json'
    });
  },
  onPrepare: function() {
    jasmine.getEnv().addReporter(new SpecReporter({ spec: { displayStacktrace: true } }));
  },
  seleniumAddress: 'http://selenium__hub:4444/wd/hub'
};

With the above configuration, GitLab fails with:

$ ./node_modules/.bin/protractor protractor.ci.conf.js
(node:3702) DeprecationWarning: os.tmpDir() is deprecated. Use os.tmpdir() instead.
[09:53:27] I/launcher - Running 1 instances of WebDriver
[09:53:27] I/hosted - Using the selenium server at http://selenium__hub:4444/wd/hub
[09:53:28] E/launcher - Error forwarding the new session Empty pool of VM for setup Capabilities [{phantomjs.binary.path=./node_modules/phantomjs-prebuilt/bin/phantomjs, count=1, browserName=phantomjs}]
[09:53:28] E/launcher - WebDriverError: Error forwarding the new session Empty pool of VM for setup Capabilities [{phantomjs.binary.path=./node_modules/phantomjs-prebuilt/bin/phantomjs, count=1, browserName=phantomjs}]
    at Object.checkLegacyResponse (/builds/netaachen/operator-app/node_modules/selenium-webdriver/lib/error.js:505:15)
    at parseHttpResponse (/builds/netaachen/operator-app/node_modules/selenium-webdriver/lib/http.js:509:13)
    at doSend.then.response (/builds/netaachen/operator-app/node_modules/selenium-webdriver/lib/http.js:440:13)
    at process._tickCallback (internal/process/next_tick.js:109:7)
From: Task: WebDriver.createSession()
    at Function.createSession (/builds/netaachen/operator-app/node_modules/selenium-webdriver/lib/webdriver.js:777:24)
    at createDriver (/builds/netaachen/operator-app/node_modules/selenium-webdriver/index.js:167:33)
    at Builder.build (/builds/netaachen/operator-app/node_modules/selenium-webdriver/index.js:632:14)
    at Hosted.getNewDriver (/builds/netaachen/operator-app/node_modules/protractor/lib/driverProviders/driverProvider.ts:60:29)
    at Runner.createBrowser (/builds/netaachen/operator-app/node_modules/protractor/lib/runner.ts:225:39)
    at q.then.then (/builds/netaachen/operator-app/node_modules/protractor/lib/runner.ts:391:27)
    at _fulfilled (/builds/netaachen/operator-app/node_modules/protractor/node_modules/q/q.js:834:54)
    at self.promiseDispatch.done (/builds/netaachen/operator-app/node_modules/protractor/node_modules/q/q.js:863:30)
    at Promise.promise.promiseDispatch (/builds/netaachen/operator-app/node_modules/protractor/node_modules/q/q.js:796:13)
    at /builds/netaachen/operator-app/node_modules/protractor/node_modules/q/q.js:556:49
[09:53:28] E/launcher - Process exited with error code 199
ERROR: Build failed: exit code 1

Answer 1

The key is to use Xvfb on GitLab CI. That spins up the display so --headless Chrome can run the specs.

I wrapped more info and chunks of code into the blog post of How to run AngularJS end-to-end tests on GitLab CI.

Answer 2

I have neved used Gitlab CI but have Selenium experience. So let me first describe some important considerations:

1. An error you receive means that there's no requested browser in the hub. This is probably because PhantomJS did not manage to register.
2. You don't need to install neither Java nor Selenium server to work with PhantomJS. It is a standalone binary implementing itself Selenium protocol. So in order to work with PhantomJS - just start container with PhantomJS. For example I would use this one: selenoid/phantomjs:2.1.1 (build file is here) - it just runs phantomjs --webdriver=4444. PhantomJS by default listens on port 8910 but because of command above we can still use 4444.
3. I think you also don't need to use webdriver-manager which is a Javascript tool to download Selenium server or webdriver binaries. This is not needed to work with PhantomJS.
4. Not sure why environment variables like HUB_PORT_4444_TCP_ADDR were added. So I would remove them all.

Having said that let's try to modify your files.

gitlab-ci.yml becomes:

image: node:7

services:
  - selenoid/phantomjs:2.1.1

stages:
  - test

test:
  stage: test
  before_script:
    - npm install -s -g @angular/[email protected]
    - npm install -s
  script:
    - ./node_modules/.bin/protractor protractor.ci.conf.js

protractor.ci.conf.js becomes (only changed container name in seleniumAddress):

/*global jasmine */
const { SpecReporter } = require('jasmine-spec-reporter');

exports.config = {
  allScriptsTimeout: 11000,
  specs: [
    './e2e/**/*.e2e-spec.ts'
  ],
  capabilities: {
    'browserName': 'phantomjs',
    'phantomjs.binary.path': './node_modules/phantomjs-prebuilt/bin/phantomjs'
  },
  directConnect: false,
  baseUrl: 'http://localhost:4200/',
  framework: 'jasmine',
  jasmineNodeOpts: {
    showColors: true,
    defaultTimeoutInterval: 30000,
    print: function() {}
  },
  beforeLaunch: function() {
    require('ts-node').register({
      project: 'e2e/tsconfig.e2e.json'
    });
  },
  onPrepare: function() {
    jasmine.getEnv().addReporter(new SpecReporter({ spec: { displayStacktrace: true } }));
  },
  seleniumAddress: 'http://selenoid__phantomjs:4444/wd/hub'
};

Not sure what is baseUrl - seems to be some Protractor stuff, so I think don't need to change. Please ask more questions if any.