[api] Add Failover field to Backend

[arkodg]

Adds a failover field to Backend API so we can support Active/Passive Failove backends within xRoutes similar to #4033

Relates to #3055

[arkodg]

cc @alexwo

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.93%. Comparing base (ada279e) to head (35eb8e3).
Report is 11 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4099      +/-   ##
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- Coverage   67.94%   67.93%   -0.02%     
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  Files         187      187              
  Lines       23029    23029              
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- Hits        15647    15644       -3     
- Misses       6266     6268       +2     
- Partials     1116     1117       +1     

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[guydc]

not imeplemented hide? Or do you plan on implementing this in the near future?

[arkodg]

plan on adding it in a follow up PR but I'll add the tag

[ferdinandosimonetti]

Hello, I'm using the Envoy Gateway version 1.1.2 and (according to kubectl explain httproute.spec.rules.backendRefs) the new field is not available.
Any hints on whether the discussed failover field will be implemented, and in which official release?
Thanks in advance
Best regards

[zirain]

Hello, I'm using the Envoy Gateway version 1.1.2 and (according to kubectl explain httproute.spec.rules.backendRefs) the new field is not available. Any hints on whether the discussed failover field will be implemented, and in which official release? Thanks in advance Best regards

should be v1.2

[ferdinandosimonetti]

Hello, I'm using the Envoy Gateway version 1.1.2 and (according to kubectl explain httproute.spec.rules.backendRefs) the new field is not available. Any hints on whether the discussed failover field will be implemented, and in which official release? Thanks in advance Best regards

should be v1.2

If someone wants to test this feature before the 1.2 release, it is possible to do that by installing v0.0.0-latest Helm Chart? Thanks again!

[zirain]

yes, normally new feature won't be backported.

[ferdinandosimonetti]

Sorry. I didn't understand.
I have currently v0.0.0-latest Helm Chart version installed, that took along its CRDs.

But this HTTPRoute

---
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: backend
  namespace: default
spec:
  parentRefs:
    - name: test-fsmn-xyz
      sectionName: https
  hostnames:
    - "test0.fsmn.xyz"
  rules:
    - backendRefs:
        - group: ""
          kind: Service
          name: backend
          port: 3000
        - group: ""
          kind: Service
          name: backend2
          port: 3000
          failover: True
      matches:
        - path:
            type: PathPrefix
            value: /

won't apply

strict decoding error: unknown field "spec.rules[0].backendRefs[1].failover"

Did I misunderstand the intended placement of the Failover: attribute?

[arkodg]

Sorry. I didn't understand. I have currently v0.0.0-latest Helm Chart version installed, that took along its CRDs.

But this HTTPRoute

---
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: backend
  namespace: default
spec:
  parentRefs:
    - name: test-fsmn-xyz
      sectionName: https
  hostnames:
    - "test0.fsmn.xyz"
  rules:
    - backendRefs:
        - group: ""
          kind: Service
          name: backend
          port: 3000
        - group: ""
          kind: Service
          name: backend2
          port: 3000
          failover: True
      matches:
        - path:
            type: PathPrefix
            value: /

won't apply

strict decoding error: unknown field "spec.rules[0].backendRefs[1].failover"

Did I misunderstand the intended placement of the Failover: attribute?

hey the field was renamed to fallback and its part of the Backend API, not backendRef
https://gateway.envoyproxy.io/latest/api/extension_types/#backendspec
this is an unreleased feature, but you can try it out with v0.0.0-latest .
You'll need to setup health checks in the BackendTrafficPolicy to make sure this works. The docs highlighting this should be out soon