How to change default listening port for SpinApp?

[Mossaka]

It seems to me that the SPIN_HTTP_LISTEN_ADDR is hard-coded in the deployment.go (i.e. https://github.com/spinkube/spin-operator/blob/main/internal/controller/deployment.go#L121-L124). Suggest: maybe we should add port to SpinAppSpec to control what listening port the app is listening on?

[endocrimes]

There's a little historical context in #266 - I'm curious as to what led to wanting to change the port here? (I've been thinking about changing it to non-80 as part of running as non-root by default at some point, but haven't come across a reason as to why you'd want to actively configure it yet?)

[Mossaka]

The motivation is to add multi-container support #325 which may take port 80.

[endocrimes]

hmm I think for a first stab we can require them not use p80 (if we wanna change ports I'd like us to think about the broader network topology / runAsNonRoot / ... all the other bits, before we just give folks a port flag that we need to migrate/drop later).

That kinda ties into the Nginx example (where if you want to do a secondary ingress thing, you'd need more control over the overall network topology and service binding for it to be effective).