Fixes Readiness Check for statefulsets using partitioned rolling update.

[amannijhawan]

Fixes #11773

What this PR does / why we need it:
This change updates readiness check in ready.go to correctly account for statefulsets that are utilizing a partitioned upgrade. These statefulsets only upgrade a subset of the managed pods with each call to helm upgrade. This causes the upgrade to legitimately hit the condition where sts.status.CurrentRevision != sts.Status.UpdateRevision which causes helm to mark the upgrade has failed when in fact it is successful.

This change fixes that behavior to only check when partition is unspecified or 0.

Special notes for your reviewer:

If applicable:

• [*] this PR contains unit tests
• [*] this PR has been tested for backwards compatibility

[bhavin192]

Note: I'm not a maintainer, but I have modified a line from this code in past, so thought of reviewing this PR.

Can you add test cases for this scenario here

helm/pkg/kube/ready_test.go

Line 127 in 76157c6

func Test_ReadyChecker_statefulSetReady(t *testing.T) {

Also, follow:

• https://github.com/helm/helm/blob/main/CONTRIBUTING.md#sign-your-work

[gjenkins8]

+1 to @bhavin192 suggestion to add a test

[amannijhawan]

Thanks @gjenkins8 @bhavin192 , I will rework the PR to add a test.

[amannijhawan]

Thanks added tests and sign off comments.

[amannijhawan]

Hi Helm Maintainers,
We are currently blocked on upgrading our packaged version of helm with yugabyte because of this issue and the existing version 3.8 has open CVEs that are fixed with 3.11.x releases.

Would it be possible to expedite the review so that we can get this into the next patch release.

Thanks
Aman

[amannijhawan]

Gentle Bump for this PR.

[gjenkins8]

LGTMe (non-maintainer; will add to helm dev weekly agenda)

[gjenkins8]

Couple of extra notes for additional reviewers. Issue #11773 Has additional details too.

Was broken by: #10622
Kubectl logic: https://github.com/kubernetes/kubectl/blob/3ec401449e5821ad954942c7ecec9d2c90ecaaa1/pkg/polymorphichelpers/rollout_status.go#L136-L145

[amannijhawan]

Thanks for the help @TerryHowe @gjenkins8 .

[amannijhawan]

Gentle bump again for this PR.

[amannijhawan]

As discussed verified on kubernetes 1.18 using minikube

[centos@dev-server-anijhawan-4 example]$ ~/helm/bin/helm version
version.BuildInfo{Version:"v3.11+unreleased", GitCommit:"ca9ba308040a27c2a23b9a9efd2325d5b849961c", GitTreeState:"clean", GoVersion:"go1.18.3"}
[centos@dev-server-anijhawan-4 example]$ kubectl version
WARNING: This version information is deprecated and will be replaced with the output from kubectl version --short.  Use --output=yaml|json to get the full version.
Client Version: version.Info{Major:"1", Minor:"26", GitVersion:"v1.26.3", GitCommit:"9e644106593f3f4aa98f8a84b23db5fa378900bd", GitTreeState:"clean", BuildDate:"2023-03-15T13:40:17Z", GoVersion:"go1.19.7", Compiler:"gc", Platform:"linux/amd64"}
Kustomize Version: v4.5.7
Server Version: version.Info{Major:"1", Minor:"18", GitVersion:"v1.18.0", GitCommit:"9e991415386e4cf155a24b1da15becaa390438d8", GitTreeState:"clean", BuildDate:"2020-03-25T14:50:46Z", GoVersion:"go1.13.8", Compiler:"gc", Platform:"linux/amd64"}
WARNING: version difference between client (1.26) and server (1.18) exceeds the supported minor version skew of +/-1

Repro of the bug

[centos@dev-server-anijhawan-4 example]$ kubectl get pods -n repro
NAME  READY  STATUS  RESTARTS  AGE
web-0  1/1   Running  0     79s
web-1  1/1   Running  0     78s
web-2  1/1   Running  0     77s

[centos@dev-server-anijhawan-4 example]$ helm upgrade helm-test ./ --debug --timeout=100s --wait --values=upgrade.yaml -n repro
upgrade.go:144: [debug] preparing upgrade for helm-test
upgrade.go:152: [debug] performing update for helm-test
upgrade.go:324: [debug] creating upgraded release for helm-test
client.go:396: [debug] checking 2 resources for changes
client.go:675: [debug] Looks like there are no changes for Service "nginx"
client.go:684: [debug] Patch StatefulSet "web" in namespace repro
upgrade.go:396: [debug] waiting for release helm-test resources (created: 0 updated: 2 deleted: 0)
wait.go:48: [debug] beginning wait for 2 resources with timeout of 1m40s
ready.go:362: [debug] StatefulSet is not ready: repro/web. update has not yet been observed
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:398: [debug] StatefulSet is not ready: repro/web. currentRevision web-6b4fd5c9f6 does not yet match updateRevision web-98b6f67cf
ready.go:398: [debug] StatefulSet is not ready: repro/web. currentRevision web-6b4fd5c9f6 does not yet match updateRevision web-98b6f67cf
ready.go:398: [debug] StatefulSet is not ready: repro/web. currentRevision web-6b4fd5c9f6 does not yet match updateRevision

upgrade.go:436: [debug] warning: Upgrade "helm-test" failed: timed out waiting for the condition
Error: UPGRADE FAILED: timed out waiting for the condition
helm.go:84: [debug] timed out waiting for the condition
UPGRADE FAILED
main.newUpgradeCmd.func2
	helm.sh/helm/v3/cmd/helm/upgrade.go:203
github.com/spf13/cobra.(*Command).execute
	github.com/spf13/cobra@v1.6.1/command.go:916
github.com/spf13/cobra.(*Command).ExecuteC
	github.com/spf13/cobra@v1.6.1/command.go:1044
github.com/spf13/cobra.(*Command).Execute
	github.com/spf13/cobra@v1.6.1/command.go:968
main.main
	helm.sh/helm/v3/cmd/helm/helm.go:83
runtime.main
	runtime/proc.go:250
runtime.goexit
	runtime/asm_386.s:1326

Verifying the patch

[centos@dev-server-anijhawan-4 example]$ ~/helm/bin/helm upgrade helm-test ./ --debug --timeout=100s --wait --values=upgrade.yaml -n repro
upgrade.go:142: [debug] preparing upgrade for helm-test
upgrade.go:150: [debug] performing update for helm-test
upgrade.go:322: [debug] creating upgraded release for helm-test
client.go:396: [debug] checking 2 resources for changes
client.go:675: [debug] Looks like there are no changes for Service "nginx"
client.go:684: [debug] Patch StatefulSet "web" in namespace repro
upgrade.go:394: [debug] waiting for release helm-test resources (created: 0 updated: 2 deleted: 0)
wait.go:48: [debug] beginning wait for 2 resources with timeout of 1m40s
ready.go:362: [debug] StatefulSet is not ready: repro/web. update has not yet been observed
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:388: [debug] StatefulSet is not ready: repro/web. 0 out of 1 expected pods have been scheduled
ready.go:404: [debug] StatefulSet is ready: repro/web. 3 out of 3 expected pods are ready
upgrade.go:157: [debug] updating status for upgraded release for helm-test
Release "helm-test" has been upgraded. Happy Helming!
NAME: helm-test
LAST DEPLOYED: Wed Mar 22 23:19:48 2023
NAMESPACE: repro
STATUS: deployed
REVISION: 3
TEST SUITE: None
USER-SUPPLIED VALUES:
replicaCount: 3
resources:
 requests:
  cpu: 100m
  memory: 512Mi
  storage: 2Gi
rollingUpdate:
 partition: 2

COMPUTED VALUES:
replicaCount: 3
resources:
 requests:
  cpu: 100m
  memory: 512Mi
  storage: 2Gi
rollingUpdate:
 partition: 2

HOOKS:
MANIFEST:
---
# Source: example/templates/sts.yaml
apiVersion: v1
kind: Service
metadata:
 name: nginx
 labels:
  app: nginx
spec:
 ports:
 - port: 80
  name: web
 clusterIP: None
 selector:
  app: nginx
---
# Source: example/templates/sts.yaml
apiVersion: apps/v1 # for k8s versions before 1.9.0 use apps/v1beta2 and before 1.8.0 use extensions/v1beta1
kind: StatefulSet
metadata:
 name: web
 labels:
  app: nginx
spec:
 updateStrategy:
  type: "RollingUpdate"
  rollingUpdate:
   partition: 2 
 serviceName: "nginx"
 selector:
  matchLabels:
   app: nginx
 replicas: 3 
 template:
  metadata:
   labels:
    app: nginx
  spec:
   containers:
   - name: nginx
    image: k8s.gcr.io/nginx-slim:0.8
    resources:
     requests:
      memory: 512Mi 
    ports:
    - containerPort: 80
     name: web
    volumeMounts:
    - name: www
     mountPath: /usr/share/nginx/html
 volumeClaimTemplates:
 - metadata:
   name: www
  spec:
   accessModes: [ "ReadWriteOnce" ]
   resources:
    requests:
     storage: 2Gi

[centos@dev-server-anijhawan-4 example]$ kubectl get pods -n repro
NAME  READY  STATUS  RESTARTS  AGE
web-0  1/1   Running  0     79s
web-1  1/1   Running  0     78s
web-2  1/1   Running  0     10s

[amannijhawan]

Thank you all for your help in getting this issue reviewed and merged.