Support live server tests with Selenium

[hansegucker]

Close #1854

[niklasmohrin]

Very cool, I feel that there are some parts that could be cleaned up or need some more explanation otherwise:

[niklasmohrin]

Manager group was not present, but only if all tests are run. We found that django will first run django.test.TestCase instances, then django.test.TransactionTestCase and then unittest.TestCase. After the first, the database is cleared. If only running the live server test, the database is still there when running the test.

Link dump if we try to debug this again:

• https://code.djangoproject.com/ticket/23640
• https://code.djangoproject.com/ticket/23727
• https://docs.djangoproject.com/en/5.0/howto/initial-data/#provide-initial-data-with-migrations
• https://docs.djangoproject.com/en/5.0/topics/testing/overview/#test-case-serialized-rollback
• http://atodorov.org/blog/2017/12/26/on-pytest-django-and-liveservertestcase-with-initial-data/

We concluded that we want to migrate an empty database, dump it, and use that dump as a fixture in the live server test - at least for now, to continue working on this.

[hansegucker]

@Kakadus @niklasmohrin @richardebeling Finally, the last test has been migrated and I'm ready for a final review. 🥳

[richardebeling]

Not yet fully reviewed, will have to look through most of the ported tests still, but generally this is looking very nice. Thanks!

[niklasmohrin]

Getting chromium or firefox should be a lot easier now that we have nix, we can work something out together some time if you want :)

[Kakadus]

Heey, there is a green check now! 🎉

@hansegucker do you want to take over and resolve the open threads? If not, I can also finish this : )

Things I fixed:

• we no longer supported django.contrib.auth.backends.ModelBackend, I switched to our evap.evaluation.auth.RequestAuthUserBackend (since Make natural key of userprofile unique #2249)
• increased window size so that all elements should be visible now
• compile scss&ts before testing the frontend
• separate firefox into a separate nix shell / CI job

[richardebeling]

Looking good! I especially like the changes to package.json and package-lock.json.

Haven't re-checked yet whether all ported tests assert the same things as the old tests, will need to re-do that in a final review.

[richardebeling]

If someone uses the SkipLiveServerTestsRunner and passes tags or exclude_tags here, it doesn't skip live server tests anymore. I'd either expect us to just add "live-server" to exclude_tags, or at least assert that neither tags or exclude_tags was set (if we never expect this to happen). The current approach of continuing but with behavior that doesn't match the class name, to me, is just a trap we set.

[Kakadus]

I think adding --tags live-server to start the live servers is reasonable. To mitigate the other stuff, I think this is most intuitive

Suggested change

	if not self.tags and not self.exclude_tags:
	self.exclude_tags = {"live-server"}
	if "live-server" not in self.tags:
	self.exclude_tags.add("live-server")

[Kakadus]

Maybe also a constant for the "live-server" tag?

[richardebeling]

3080 intended? Or should it be 1080?

[Kakadus]

yes, the height should be large enough so that there is no scrolling needed. Maybe worth a comment?

[Kakadus]

I changed this so that the values selected in the UI are not already selected. I found out this was intended to be a test for #1769 but I could not find there that this is required for this

[Kakadus]

I'm going to rebase this and sort the changes