fix(labelling): hotfix for issues related to deploy erroring due to nested yaml field overriding in StatefulSet w/ PVC

[aaron-prindle]

Hotfix for an issue that is being seen in which when skaffold attempts to redeploy manifests with nested objects and "immutable" fields, skaffold fails as it will attempt to override the label/image when doing so will result in a deployment error.

Minimal repro:

Skaffold.yaml

apiVersion: skaffold/v2beta12
kind: Config
deploy:
  kubectl:
    manifests:
      - k8-*

k8-pod.yaml:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  selector:
    matchLabels:
      app: echoserver # has to match .spec.template.metadata.labels
  serviceName: "echoserver"
  replicas: 3 # by default is 1
  template:
    metadata:
      labels:
        app: echoserver 
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - image: k8s.gcr.io/echoserver:1.4
        name: echoserver
        volumeMounts:
        - name: www
          mountPath: /usr/share/nginx/html
  volumeClaimTemplates:
  - metadata:
      name: www
    spec:
      accessModes: [ "ReadWriteOnce" ]
      resources:
        requests:
          storage: 1Gi

run "skaffold deploy" twice w/o this PR fails with:

aprindle@aprindle ~/repro-6416 $ skaffold deploy
Tags used in deployment:
Starting deploy...
 - The StatefulSet "web" is invalid: spec: Forbidden: updates to statefulset spec for fields other than 'replicas', 'template', 'updateStrategy' and 'minReadySeconds' are forbidden
kubectl apply: exit status 1[

works w/ this change.

A more extensible/robust approach to fixing this issue is in progress as well that will implement something similar to the proposed idea from - #6236 (found here - https://github.com/GoogleContainerTools/skaffold/blob/main/docs/design_proposals/configurable-transformable-allowlist.md)

[codecov]

Codecov Report

Merging #7011 (31df8c8) into main (290280e) will decrease coverage by 1.71%.
The diff coverage is 56.96%.

@@            Coverage Diff             @@
##             main    #7011      +/-   ##
==========================================
- Coverage   70.48%   68.77%   -1.72%     
==========================================
  Files         515      554      +39     
  Lines       23150    25695    +2545     
==========================================
+ Hits        16317    17671    +1354     
- Misses       5776     6822    +1046     
- Partials     1057     1202     +145     

Impacted Files	Coverage Δ
cmd/skaffold/app/cmd/deploy.go	52.00% <ø> (-1.85%)	⬇️
cmd/skaffold/app/cmd/dev.go	84.61% <0.00%> (ø)
cmd/skaffold/app/cmd/render.go	36.66% <0.00%> (-4.72%)	⬇️
cmd/skaffold/skaffold.go	0.00% <0.00%> (ø)
cmd/skaffold/app/cmd/inspect_tests.go	62.50% <14.28%> (-1.14%)	⬇️
cmd/skaffold/app/cmd/lsp.go	28.12% <28.12%> (ø)
cmd/skaffold/app/cmd/fix.go	68.85% <40.00%> (-7.62%)	⬇️
cmd/skaffold/app/cmd/lint.go	42.85% <42.85%> (ø)
cmd/skaffold/app/cmd/find_configs.go	48.88% <50.00%> (+0.24%)	⬆️
cmd/skaffold/app/skaffold.go	76.19% <70.00%> (-8.43%)	⬇️
... and 181 more

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[briandealwis]

LGTM with one caveat/question: is jsonpath a valid JSONPath string? If not, could you rename jsonpath to navpath or something similar to avoid any confusion that this the contents is actually a JSONPath string?

[aaron-prindle]

LGTM with one caveat/question: is jsonpath a valid JSONPath string? If not, could you rename jsonpath to navpath or something similar to avoid any confusion that this the contents is actually a JSONPath string?

Good idea. No I don't believe it is a valid JSONPath string as we cannot get the array index values which I believe is part of that spec. I have renamed the field "navpath"