Investigate and scope Gateway API work

[knolleary]

Description

This is a research-only task so that we can better scope future engineering effort required.

Goal is to understand what changes would be needed to support Gateway API entities.

Also identify how session affinity for device agent editor can be implement in a implementation agnostic way.

Epic/Story

No response

Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate

[hardillb]

https://gateway-api.sigs.k8s.io/

https://gateway-api.sigs.k8s.io/geps/gep-1619/

[hardillb]

Current notes

• No Session Affinity yet, coming soon
• No easy way to do custom certs for custom hostnames, certs are held at the Gateway level, not the HTTPRoute level which is similar to the old Ingress object. Told ListenerSets may help with this. https://gateway-api.sigs.k8s.io/geps/gep-1713/ . This will also need an update to CertManager to support this.

[hardillb]

My current view is that until Session Affinity and ListenerSets are implemented the Gateway API is not ready for use with Flowfuse.