Warn about things that we strongly recommend avoiding

[DirectXMan12]

317 introduces support for a pattern we generally don't recommend: pointers as map values. This is mainly for a few legacy use cases that folks want to support, but I think we generally want to warn people that this isn't a pattern that we/the kube API conventions generally suggest/support.

We probably want something that looks a lot like our error reporting system, but works adds a "non-fatal" warning instead of a semi-fatal error. I'd expect something like:

pkg.AddWarning(loader.ErrorFromNode(...))

and then print out warnings at the end.

317 is the only case I know of off the top of my head, but having this infra would prob be useful in the future.

/help /good-first-issue /kind feature /priority important-soon

[k8s-ci-robot]

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In response to [this](https://github.com/kubernetes-sigs/controller-tools/issues/434): >#317 introduces support for a pattern we generally don't recommend: pointers as map values. This is mainly for a few legacy use cases that folks want to support, but I think we generally want to warn people that this isn't a pattern that we/the kube API conventions generally suggest/support. > >We probably want something that looks a lot like our error reporting system, but works adds a "non-fatal" warning instead of a semi-fatal error. I'd expect something like: > >```go >pkg.AddWarning(loader.ErrorFromNode(...)) >``` > >and then print out warnings at the end. > >#317 is the only case I know of off the top of my head, but having this infra would prob be useful in the future. > >/help >/good-first-issue >/kind feature >/priority important-soon Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes/test-infra](https://github.com/kubernetes/test-infra/issues/new?title=Prow%20issue:) repository.

[ksaritek]

I would like to give it a try :) /assign

[ksaritek]

I created a guestbook kubebuilder init project and added a *ast.StarExpr to guestbook struct

type Env struct {
    A int    `json:"a"`
    B string `json:"b"`
}

// Guestbook is the Schema for the guestbooks API
type Guestbook struct {
    metav1.TypeMeta   `json:",inline"`
    metav1.ObjectMeta `json:"metadata,omitempty"`

    Spec   GuestbookSpec   `json:"spec,omitempty"`
    Status GuestbookStatus `json:"status,omitempty"`
    Envs   map[string]*Env `json:"envs,omitempty"`
}

my patch:

./controller-gen crd object:headerFile="hack/boilerplate.go.txt" paths="./..." output:crd:stdout

---
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
  annotations:
    controller-gen.kubebuilder.io/version: (devel)
  creationTimestamp: null
  name: guestbooks.webapp.my.domain
spec:
  group: webapp.my.domain
  names:
    kind: Guestbook
    listKind: GuestbookList
    plural: guestbooks
    singular: guestbook
  scope: Namespaced
  validation:
    openAPIV3Schema:
      description: Guestbook is the Schema for the guestbooks API
      properties:
        apiVersion:
          description: 'APIVersion defines the versioned schema of this representation
            of an object. Servers should convert recognized schemas to the latest
            internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources'
          type: string
        envs:
          additionalProperties:
            properties:
              a:
                type: integer
              b:
                type: string
            required:
            - a
            - b
            type: object
          type: object
        kind:
          description: 'Kind is a string value representing the REST resource this
            object represents. Servers may infer this from the endpoint the client
            submits requests to. Cannot be updated. In CamelCase. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds'
          type: string
        metadata:
          type: object
        spec:
          description: GuestbookSpec defines the desired state of Guestbook
          properties:
            foo:
              description: Foo is an example field of Guestbook. Edit Guestbook_types.go
                to remove/update
              type: string
          type: object
        status:
          description: GuestbookStatus defines the observed state of Guestbook
          type: object
      type: object
  version: v1
  versions:
  - name: v1
    served: true
    storage: true
status:
  acceptedNames:
    kind: ""
    plural: ""
  conditions: null
  storedVersions: null
/go/src/example/api/v1/guestbook_types.go:55:20: map values should be a named type, not *ast.StarExpr

controller-gen prints warning at the end like /go/src/example/api/v1/guestbook_types.go:55:20: map values should be a named type, not *ast.StarExpr. @DirectXMan12 , it that right?

[ksaritek]

pull request: https://github.com/kubernetes-sigs/controller-tools/pull/443

[fejta-bot]

Issues go stale after 90d of inactivity. Mark the issue as fresh with /remove-lifecycle stale. Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta. /lifecycle stale

[ksaritek]

/remove-lifecycle stale

[fejta-bot]

Issues go stale after 90d of inactivity. Mark the issue as fresh with /remove-lifecycle stale. Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta. /lifecycle stale

[DirectXMan12]

/remove-lifecycle stale /lifecycle frozen