feat(trait): add support for multiple ingress paths

[cfitzw]

Related to issue #5981.

• Allow multiple paths to be set within an ingress.
• Implement a workaround to allow backward compatibility for ingress.path.
• Determine if the IngressTrait should be migrated towards adopting K8s API IngressSpec hierarchy.
  Can be reviewed again at a later point in time/in a separate PR.

Example usage:

build/_output/bin/kamel-amd64 run test/src/multi-path.yml -o yaml --trait ingress.paths="/api/v1/multi" --trait ingress.paths="/api/v1/path" > test/base/multi-path.yml

... generates:

apiVersion: camel.apache.org/v1
kind: Integration
metadata:
  annotations:
    camel.apache.org/operator.id: camel-k
  creationTimestamp: null
  name: multi-path
spec:
  flows:
  - from:
      steps:
      - set-header:
          name: Content-Type
          simple: application/json
      - set-body:
          constant: '{"welcome": "multi"}'
      uri: rest:get:/api/v1/multi
  - from:
      steps:
      - set-header:
          name: Content-Type
          simple: application/json
      - set-body:
          constant: '{"welcome": "path"}'
      uri: rest:get:/api/v1/path
  traits:
    ingress:
      paths: 
        - /api/v1/multi
        - /api/v1/path
status: {}

Output of ingress (kubectl get ingress multi-path -o yaml):

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  creationTimestamp: "2024-12-13T15:21:34Z"
  generation: 1
  labels:
    camel.apache.org/generation: "1"
    camel.apache.org/integration: multi-path
  name: multi-path
  namespace: default
  ownerReferences:
  - apiVersion: camel.apache.org/v1
    blockOwnerDeletion: true
    controller: true
    kind: Integration
    name: multi-path
    uid: eb44c65f-3dca-49e5-a368-1ba8946fc3ee
  resourceVersion: "97865"
  uid: bc5651de-87a5-40d7-be30-9375c98dfb61
spec:
  ingressClassName: nginx
  rules:
  - http:
      paths:
      - backend:
          service:
            name: multi-path
            port:
              name: http
        path: /api/v1/multi
        pathType: Prefix
      - backend:
          service:
            name: multi-path
            port:
              name: http
        path: /api/v1/path
        pathType: Prefix
status:
  loadBalancer:
    ingress:
    - ip: 192.168.49.2

Curl Output:

curl 192.168.49.2/api/v1/multi
{"welcome": "multi"}

curl 192.168.49.2/api/v1/path
{"welcome": "path"}

[github-actions]

✔️ Unit test coverage report - coverage increased from 47.2% to 47.3% (+0.1%)

[squakez]

Nice stuff, thanks! As mentioned in the issue, to avoid breaking compatibility you can keep the path logic and additionally include a paths with the logic you're willing to implement.

[cfitzw]

@squakez - I've now added paths and kept path with deprecated notices. The code will now continue to support the existing path convention.

I could use some assistance on implementing some sort of error handling so that if both path and paths traits exist, that an error is thrown. Right now I have it coded to take only the path and ignore paths when this scenario exists.
I've now just added another small commit (+test) to allow both the path and paths fields to be able to co-exist.

[github-actions]

⚠️ Unit test coverage report - coverage decreased from 47.6% to 47.3% (-0.3%)

[squakez]

Nice work, thanks! If you can give another shot and add a deprecation warning notice in the Integration condition it would be great.

[squakez]

I forgot to add a link to some example you can use for the warning notice:

camel-k/pkg/trait/builder.go

Line 96 in 023e658

condition := t.adaptDeprecatedFields()

[cfitzw]

Excellent - thank you for the example. I'll work to get this added in the coming days.