client-go/testing: Can't list deployments after scaling

[lynx-coding]

What happened:
I wanted to test my method to scale deployments. But after changing the replicas by using updateScale I was not able to list deployments anymore.

What you expected to happen:

• create fake api
• create mock deployment
• scale it
• list it

How to reproduce it (as minimally and precisely as possible):

• create fake api
• create a mock deployment
• scale the deployment
• list the deployment

Anything else we need to know?:

package scaling

import (
    "testing"

    v1api "k8s.io/api/apps/v1"
    autoscalingv1 "k8s.io/api/autoscaling/v1"
    metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/client-go/kubernetes/fake"

    "github.com/stretchr/testify/require"
)

func TestScaling(t *testing.T) {
    initialReplicas := int32(3)
    cs := fake.NewSimpleClientset()
    _, err := cs.AppsV1().Deployments("test-namespace").Create(&v1api.Deployment{
        ObjectMeta: metav1.ObjectMeta{
            Name: "test-deployment",
            Labels: map[string]string{
                "app": "test-app",
            },
        },
        Spec: v1api.DeploymentSpec{
            Replicas: &initialReplicas,
        },
    })
    require.NoError(t, err)
    scale := &autoscalingv1.Scale{
        ObjectMeta: metav1.ObjectMeta{
            Name:      "test-deployment",
            Namespace: "test-namespace",
        },
        Spec: autoscalingv1.ScaleSpec{
            Replicas: 5,
        },
    }
    _, err = cs.AppsV1().Deployments("test-namespace").UpdateScale("test-deployment", scale)
    require.NoError(t, err)
    _, err = cs.AppsV1().Deployments("test-namespace").List(metav1.ListOptions{FieldSelector: "app=test-app"})
    require.NoError(t, err)
}

Run like this:

go test -run TestScaling ./scaling

This will lead to an error like the following:

item[0]: can't assign or convert v1.Scale into v1.Deployment

Environment:

• go version: go1.13.5 linux/amd64
• client-go version: k8s.io/client-go@v0.16.4
• related issue(s)/pr(s):
  • 80354
  • 410
  • 579

[chrisseto]

I'm also encountering this issue with Statefulsets.

@lynx-coding have you had any luck with tracking down a fix or work around?

From digging around a bit, it looks like Scale is a psuedo resource rather than a true subresource which may be the cause for issues?

[fejta-bot]

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

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/lifecycle stale

[fejta-bot]

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/lifecycle rotten

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[k8s-ci-robot]

@fejta-bot: Closing this issue.

In response to this:

Rotten issues close after 30d of inactivity.
Reopen the issue with /reopen.
Mark the issue as fresh with /remove-lifecycle rotten.

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

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