Selenium is only a library, and as such it does not particularly care if you are running it on a system that is equipped with a GUI. What you are probably asking is: If I use Selenium to open a browser, is that browser going to work on a system with no GUI. The answer to this is: it depends!
There are headless browsers: browsers that also do not have a GUI component. HtmlUnit is packaged with Selenium. Another popular browser is PhantomJS, which has third-party Selenium bindings library called GhostDriver. Personally I would avoid both of these! HtmlUnit uses a JavaScript engine that none of the current desktop browsers support, and as such the tests are not very reliable. GhostDriver has not been maintained for 2 years, and as such also makes for unreliable results. PahntomJS is definitely an option, as it uses WebKit - the engine that is in Safari and Chrome browsers, but you would have to write your own API.
Most systems will allow you to have a virtual GUI. You mentioned Ubuntu, which is a Debian derivative. There are several tutorials on the Net that tell you how to install Xvfb, most of which are incomplete or wrong. On a Debian you install a headless browser like this:
- Install Xvfb:
apt-get install xvfb
- Install a browser. Assuming you are using a Debian server, you will not be able to install something like Firefox with apt-get, because the repositories are not present. Instead Google something like "Firefox off-line install", or whatever browser you want to use, and then use
wget on your server to grab the package.
- Unpack the package somewhere like
/usr/local/lib, and then create a soft link from /usr/local/bin to the binary that launches the browser.
- Now try launching your browser headless. For example, for Firefox you would try:
xvfb-run firefox. This may produce some errors, which you have to fix. In my case, I was missing the library libdbus-glib-1-2 which I could install just using apt-get.
- At this point you will need to launch Xvfb before running your Selenium tests. Most CI servers have a plugin for Xvfb, or you can do it from the command line:
Xvfb :99 &. See the docs for additional information.
