Fix WS/SSE tests and replace go backend with NodeJS

[alexpetros]

Background

The live WebSocket/Server-Side Events tests were causing us a couple problems:

• Every release that we cut we'd get flooded with dependabot spam for the golang dependencies
• The golang dependencies also spam our GitHub security tab, where all but 4 of them are from go
• A couple of the tests were allegedly not working (I didn't actually verify this myself)
• You needed to install the golang toolchain to run them, which isn't a requirement anywhere else in the project

So, to the fix the dependabot thing and partially as an excuse to learn what WebSockets are, I reimplemented the tests' backend in NodeJS.

Description

The main changes are as follows:

• I removed all the golang dependencies, at the cost of adding a single JS one (the excellent ws library). This resolves the dependabot/security issue, and removes a full language toolchain from htmx.
• I re-implemented the routing mechanism to use hard links instead of hx-boost and hx-get, so now refreshing the page takes you back the tab you were on, instead of the homepage, and links are persisted in the URL bar/history. This makes developing on them much nicer.
• The tests use relative URLs so no CORS headers are required, and the syntax is a little easier to follow
• You can run the test suite from package.json now
• The code is actually a bit smaller line-wise

And as far as I can tell, all the tests work now! There's a couple small changes to the timing of the events that I'll play around with, but what I have now gets the job done.

Testing

Run npm run ws-tests from the package root! There's also a readme in /tests/ws-sse directory with some granular instructions.

Note that the old go code is still mirrored on the website, which I left in for this PR so that the comparisons are more obvious. When we cut the next release it will go away and officially remove the the last of the go code.

Credits

Huge props to @benpate for writing the initial version of these tests. It's much easier to adapt exist code than write a whole new paradigm, and his test suite and server code was really easy to follow.

[Renerick]

LGTM

[benpate]

Hey, this looks really cool. And Javascript will probably be a better / more portable environment to do this than Go has been. Awesome work :)

[alexpetros]

That means a lot, thank you Ben :)

[nickchomey]

Amazing work.

Perhaps it is irrelevant for these purposes, but https://github.com/uNetworking/uWebSockets.js/ is known to be by far the fastest/most powerful nodejs websockets library. It might be worth taking a look, as it would be a useful tool for production as well.

The author's blog is quite informative (if inflammatory at times). https://unetworkingab.medium.com/the-story-of-uws-so-far-493ac0c05ccb

Here's another good one as well https://edisonchee.com/writing/intro-to-%C2%B5websockets.js/

[alexpetros]

@nickchomey That's great to know, these are good reads. I do think for the test purposes that I'll stick with ws—it's popular and has no dependencies, so I feel pretty good about that it will correctly run the tests more or less indefinitely, which is my main priority here.