Interactive, multiplayer LiveView Testing

Not sure how this module might help - GitHub - processone/tsung: Tsung is a high-performance benchmark framework for various protocols including HTTP, XMPP, LDAP, etc. · GitHub

Thanks @HappyBee or the suggestion. I’m looking at it.

Your response prompted me to think about and refine what my concern is.

Since my app is a multiplayer experience and the actions of one person are PubSub pushed through LiveView to the other players.

How do I test N users playing the same game, they each take their turn within a few seconds of each other. They’ll receive updates from the other n-1 players. Can they keep up with the PLV socket deltas? What if their connectivity is poor (nod to the latency sim) or they have an older device?

The way we do this on most projects that solve business problems is to send metrics from the parts of system you care about. What is even nicer is that a lot of libraries emit them by default, all you have to do is hook to them, for example phoenix: Telemetry — Phoenix v1.8.8

In that way, you can later query them and analyze your overall performance of the system and find the bottlenecks.

There is also the option of spinning up another instance that is as close as possible to what you have in prod and create a custom stress testing client. I highly doubt there is any libraries for doing this, so it’s up to you to build this from scratch. This approach has its own benefits, however the effort investment in making this work correctly is times bigger than the above approach.

I think using telemetry is the way to go. Although it might be a very good idea to have manual tests as well. I guess you will have a max number of simultaneous users.
I would deploy it on a production server and get some friends, a crate of beer and start testing.
When those tests work as expected, I would continue with a closed beta test with a limited number of players.
And then slowly add more players via additional slots.
And while you do this, always track your telemetry data.