[keycloak-dev] Improving testsuite performance

ATM running tests in the new arquillian testsuite ( testsuite/integration-arquillian ) is significantly slower then running tests in the old testsuite ( testsuite/integration ). It was quite visible in some tests, which were around 3 times slower after they were migrated from the old testsuite. We found that there are 2 major bottlenecks causing it: - There is re-import of all the realms before each test method. In the old testsuite, it was just BeforeClass. - The new testsuite uses phantomjs WebDriver by default. The old one used htmlUnit. I've checked that phantomjs is around 15-times slower than htmlUnit. The main reason is that htmlUnit talks directly with the tested server, when phantomJS (similarly like all other real browsers) uses remote selenium server, which adds significant overhead. For example all the simple operations like "driver.getTitle()" needs to send HTTP request to the selenium server. Hence I've looked at the possibility to switch to htmlUnit by default and sent PR for it: https://github.com/keycloak/keycloak/pull/3876 . New testsuite runs on my laptop in 21 minutes with htmlUnit, when previously it was 36 minutes. However there is the disadvantage, that htmlUnit has limited javascript support and is not the best for angular apps. It seems that admin console tests won't run with it. I also needed to do some refactoring of few existing tests to have them pass with htmlUnit (eg. AbstractDemoServletsAdapterTest to use assertEvents instead of admin console etc). However this won't be an issue as browser implementation can be overriden with: -Dbrowser=phantomjs So it's possible to run console tests with proper browsers. Anyone seeing issues with switch to htmlUnit by default? I hope that after fix the import + maybe few other things (eg. share adminClient per class instead of test method etc), we will be able to run whole testsuite in less than 15 minutes! Thanks, Marek