When removing fields from the yaml body, they are not removed from the applied manifest

[svanharmelen]

When using the kubectl_manifest resource it only seems to update existing fields or add new fields to a deployed/applied manifest, but when you remove a field, the field is not removed from the manifest.

Is that by design or am I doing something wrong? I tried using server side applies but that didn't seem to make any differences.

[alekc]

Can you provide an example?

…

On Tue, 24 Sept 2024, 11:04 Sander van Harmelen, ***@***.***> wrote: When using the kubectl_manifest resource it only seems to update existing fields or add new fields to a deployed/applied manifest, but when you remove a field, the field is not removed from the manifest. Is that by design or am I doing something wrong? I tried using server side applies but that didn't seem to make any differences. — Reply to this email directly, view it on GitHub <#174>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACJ5VZGV4JRPLCSSTUFYPDZYE2MNAVCNFSM6AAAAABOX5URTGVHI2DSMVQWIX3LMV43ASLTON2WKOZSGU2DIOJVGAZTSMI> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[svanharmelen]

I think so, will see if I can create a simple test case that I can share...

[svanharmelen]

Didn't forget this one, but need to find some time. Maybe I can make some time this weekend. Will update when I have something you can test with...

[svanharmelen]

Sorry for taking so long! I just encountered this again today and will try to make a simple example in the coming days!

[svanharmelen]

When trying to make a custom example it turns out I cannot reproduce it. So I'm assuming that whatever I saw, was not due to this resource but probably due to an operator also touching the same resource. Going to dig into that one further and will close this issue...

[svanharmelen]

Well, maybe it's still a bug in this resource 😏

If I apply this CRD:

apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  name: removals.stable.example.com
spec:
  group: stable.example.com
  versions:
    - name: v1
      served: true
      storage: true
      schema:
        openAPIV3Schema:
          type: object
          properties:
            spec:
              type: object
              properties:
                config:
                  type: object
                  x-kubernetes-preserve-unknown-fields: true
  scope: Namespaced
  names:
    plural: removals
    singular: removal
    kind: Removal
    shortNames:
    - rms

And then apply a TF config like this:

resource "kubectl_manifest" "test" {
  yaml_body = yamlencode({
    apiVersion = "stable.example.com/v1"
    kind       = "Removal"
    metadata = {
      name      = "test"
      namespace = "default"
    }
    spec = {
      config = {
        key1 = "value1"
        key2 = "value2"
      }
    }
  })
}

I have a resource like I would expect:

apiVersion: stable.example.com/v1
kind: Removal
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"stable.example.com/v1","kind":"Removal","metadata":{"annotations":{},"name":"test","namespace":"default"},"spec":{"config":{"key1":"value1","key2":"value2"}}}
  creationTimestamp: "2024-10-29T17:55:11Z"
  generation: 11
  name: test
  namespace: default
  resourceVersion: "68102"
  uid: bf3b6028-3860-48f9-b7d6-a62134c38cf8
spec:
  config:
    key1: value1
    key2: value2

But if I then manually edit the resource directly in k8s (I understand this is something you should not do, but in this case there is a (reasonable complex) reason why one of our k8s operators sometimes needs to do this) giving it an additional field like this:

apiVersion: stable.example.com/v1
kind: Removal
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"stable.example.com/v1","kind":"Removal","metadata":{"annotations":{},"name":"test","namespace":"default"},"spec":{"config":{"key1":"value1","key2":"value2"}}}
  creationTimestamp: "2024-10-29T17:55:11Z"
  generation: 11
  name: test
  namespace: default
  resourceVersion: "68102"
  uid: bf3b6028-3860-48f9-b7d6-a62134c38cf8
spec:
  config:
    key1: value1
    key2: value2
    some: thing # <- this one is added

And then refresh and apply the existing TF config, it says there are no changes. And if I update the config to something like this:

resource "kubectl_manifest" "test" {
  yaml_body = yamlencode({
    apiVersion = "stable.example.com/v1"
    kind       = "Removal"
    metadata = {
      name      = "test"
      namespace = "default"
    }
    spec = {
      config = {
        key1 = "value1"
        key3 = "value3" # <= this changed from 'key2 = "value2"'
      }
    }
  })
}

It only sees that change, but ignores (doesn't even show) the value that was manually added:

So is this a bug, or is there a setting that can be used to "fix" this?