支持 Openshift Route 模型

[zhugelianglongming]

背景

K8s 环境中已通过 Openshift Route 配置部分路由，希望 bfe-ingress-controller 兼容。

• Route CRD

配置示例

apiVersion: route.openshift.io/v1
kind: Route
metadate:
  name: app
  namespace: default
spec:
  alternateBackends:
  - kind: Service
    name: app1
    weight: 20
  host: example.com
  path: /
  port:
    targetPort: 8080
  to:
    kind: Service
    name: app
    weight: 80
  wildcardPolicy: None

[ps1976]

Reference
Ingress (V1) model: https://github.com/kubernetes/api/blob/master/networking/v1/types.go
Openshift Route model: https://github.com/openshift/api/blob/master/route/v1/types.go

[ps1976]

Main diff btw the two models -

#1. TLS config -

• Ingress reuses k8s secret tls config with proper name
• Route configures key & cert in its spec with termination type

#2. Path -

• An ingress spec has a path array with PathTypes(Exact, Prefix, ImplementationSpecific)
• One route spec has just one path entry without PathType (Somehow reasonable that one route entry only contains one path)

#3. Backend -

• An ingress can have a default backend and specify a backend in an ingress rule
• A route can set a To backend and at most 3 alternative backends for one path with weights

#4. Balance weight -

• BFE ingress uses annotation to set the balance weight - Weight values are assigned to sub-services that constructs a service which is specified in backend service name in a rule
• A route assigns weight for different backend (To + alternative) in the spec, and the weight ranges from 0 to 256 with default 100

#5. Annotations -

• Customize new annotations for openshift route in accordance with BFE annotation definitions (cookie, header, redirct, etc)

#6. IngressClass -

• Should openshift route have such annotation?