feat: Operator - make server container creation explicit in the CR

[tchughesiv]

What this PR does / why we need it:

Currently, the operator creates a running server/container for each feast service by default. This is unnecessary and should only be done on an as-needed basis. With this change, the user will have to explicitly configure a new server subsection for a given service type (online/offline/etc). Otherwise, the operator will not run a separate container w/ remote server for that service. By default, the registry container will continue created.

Which issue(s) this PR fixes:

Fixes #5023

Misc

In the following example the online store, but NOT the offline, would have a separate container running a remote online feature server. The offline persistence configs, however, would still be reflected in the shared feature_store.yaml.

apiVersion: feast.dev/v1alpha1
kind: FeatureStore
metadata:
  name: example
spec:
  feastProject: my_project
  services:
    offlineStore:
      persistence:
        file:
          type: duckdb
    onlineStore:
      server: {}

an example of some of the optional fields within this server object -

      server:
        image: 'feastdev/feature-server:0.45.0'
        logLevel: debug
        tls:
          secretKeyNames:
            tlsCrt: tls.crt
            tlsKey: tls.key
          secretRef:
            name: feast-sample-all-servers-online-tls
        envFrom:
          - secretRef:
              name: postgres-secret
        resources:
          requests:
            cpu: 150m
            memory: 128Mi

[redhatHameed]

@tchughesiv WDYT
if we can just flag remote it will be be false for offline server, for online always true

example

apiVersion: feast.dev/v1alpha1
kind: FeatureStore
metadata:
  name: sample-all-services
spec:
  feastProject: my_project
  services:
    onlineStore:
      remote: true
    offlineStore:
      remote: false
    registry:
      remote:?

if this is just for offline server setting we just go with this settings

apiVersion: feast.dev/v1alpha1
kind: FeatureStore
metadata:
  name: sample-all-services
spec:
  feastProject: my_project
  services:
    onlineStore {}
    offlineStore:
      remote: false
    registry:
      local: {}

[tmihalac]

Are you sure a one line function like this is needed?

[tchughesiv]

unfortunately yes... the alternative would be separate vars for each.

[redhatHameed]

@tchughesiv WDYT if we can just flag remote it will be be false for offline server, for online always true

example

apiVersion: feast.dev/v1alpha1
kind: FeatureStore
metadata:
  name: sample-all-services
spec:
  feastProject: my_project
  services:
    onlineStore:
      remote: true
    offlineStore:
      remote: false
    registry:
      remote:?

if this is just for offline server setting we just go with this settings

apiVersion: feast.dev/v1alpha1
kind: FeatureStore
metadata:
  name: sample-all-services
spec:
  feastProject: my_project
  services:
    onlineStore {}
    offlineStore:
      remote: false
    registry:
      local: {}

Thanks, @tchughesiv for explaining on this on meet/call, I am good to keep current approach using sever section

[redhatHameed]

lgtm