What about Selenium? Is it already covered in point 2?
Well, some people also ask why world ever need Ruby with Rails or Python with Django? You can write any website in Enterprise Java since late 1990s. Same Docker vs. Virtual Machines or Atom vs. Vim/Emacs. Even if capability is there, there is room for improvement. Especially if you can make it easier to use and make developers more productive by an order of magnitude.
I would recommend not working with WebDriver directly. There are many projects that wrap it in a sane API and make it very easy to use. For example if you're using Javascript then use http://webdriver.io instead of directly using the Selenium WebDriver API.
> IMO it is hard to setup and resource consuming
What issues have you had? It's always been very easy to setup in my experience.
The only two 'issues' I've had are correct management of the Selenium server within a task running context and odd interactions with some browsers when they are driven by selenium (e.g. safari considering `window.open()` to always be a popup from selenium triggered actions).
Btw, can you point me to some tutorial that teach you in 15 minutes from zero how to setup something that can change any url into a thumbnail screen shoot. You can do that with phantomjs:
brew install phantomjs
http://phantomjs.org/screen-capture.html
Maybe a selenium pro can do it quickly, but for me:
1. How to install selenium? It took me few attempts until I realized that Docker containers are the best way.
2. Install Docker on MacOS and start container.
3. Find some toolkit that talks to selenium. There are tons of libraries, but just some have reasonable docs and are well maintained.
4. Configure this toolkit so it can talk to Selenium.
5. Beware if your container die. Also figuring out that website is loaded is also non-trivial in Selenium and default are worse than in PhantomJS.
6. Etc.
To get things started simply with JS just follow instructions here: http://webdriver.io/guide.html
The only major diversions from that are to use Mocha or Jasmine for your test framework (instructions on the same site) and to automate starting / stopping the selenium server for which there are grunt/gulp plugins.