Custom MONGODB_REPO_URL doesn't take MDB_IMAGE_TYPE into account

[Jaybee18]

What did you do to encounter the bug?
Steps to reproduce the behavior:

1. Configure the mongodb community operator with helm and the values.yaml (provided at https://raw.githubusercontent.com/mongodb/helm-charts/refs/heads/main/charts/community-operator/values.yaml). Notice that this is pretty much unaltered except that mongodb.repo is a custom repo:
   (I did not test this exact file, but the error should still occur as I explained further down; if not, i can provide more information)

## Reference to one or more secrets to be used when pulling images
## ref: https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/
imagePullSecrets:
 - name: "image-pull-secret-for-my-custom-repo"
## Operator
operator:
  # Name that will be assigned to most of internal Kubernetes objects like
  # Deployment, ServiceAccount, Role etc.
  name: mongodb-kubernetes-operator

  # Name of the operator image
  operatorImageName: mongodb-kubernetes-operator

  # Name of the deployment of the operator pod
  deploymentName: mongodb-kubernetes-operator

  # Version of mongodb-kubernetes-operator
  version: 0.11.0

  # Uncomment this line to watch all namespaces
  watchNamespace: "*"

  # Resources allocated to Operator Pod
  resources:
    limits:
      cpu: 1100m
      memory: 1Gi
    requests:
      cpu: 500m
      memory: 200Mi

  # PriorityClass configuration for operator
  # ref: https://kubernetes.io/docs/concepts/scheduling-eviction/pod-priority-preemption/#priorityclass
  priorityClassName: ''

  # replicas deployed for the operator pod. Running 1 is optimal and suggested.
  replicas: 1

  # Additional environment variables
  extraEnvs: []
  # environment:
  # - name: CLUSTER_DOMAIN
  #   value: my-cluster.domain

  podSecurityContext:
    runAsNonRoot: true
    runAsUser: 2000

  securityContext: {}

## Operator's database
database:
  name: mongodb-database
  # set this to the namespace where you would like
  # to deploy the MongoDB database,
  # Note if the database namespace is not same
  # as the operator namespace,
  # make sure to set "watchNamespace" to "*"
  # to ensure that the operator has the
  # permission to reconcile resources in other namespaces
  # namespace: mongodb-database

agent:
  name: mongodb-agent-ubi
  version: 107.0.7.8596-1
versionUpgradeHook:
  name: mongodb-kubernetes-operator-version-upgrade-post-start-hook
  version: 1.0.9
readinessProbe:
  name: mongodb-kubernetes-readinessprobe
  version: 1.0.20
mongodb:
  name: mongodb-community-server
  repo: my.custom.repo/folder/docker.io/mongodb # <-- custom repo
  imageType: ubi8

registry:
  agent: quay.io/mongodb
  versionUpgradeHook: quay.io/mongodb
  readinessProbe: quay.io/mongodb
  operator: quay.io/mongodb
  pullPolicy: Always

# Set to false if CRDs have been installed already. The CRDs can be installed
# manually from the code repo: github.com/mongodb/mongodb-kubernetes-operator or
# using the `community-operator-crds` Helm chart.
community-operator-crds:
  enabled: true

2. apply the configuration

What did you expect?
When not using a custom repo for the mongodb-community-server image, the image in the StatefulSet will be docker.io/mongodb/mongodb-community-server:4.4.29-ubi8. So I expect the StatefulSet to be configured to pull my.custom.repo/folder/docker.io/mongodb/mongodb-community-server:4.4.29-ubi8 when using a custom repo.

What happened instead?
The StatefulSet will be configured to pull my.custom.repo/folder/docker.io/mongodb/mongodb-community-server:4.4.29 instead of my.custom.repo/folder/docker.io/mongodb/mongodb-community-server:4.4.29-ubi8, missing the -ubi8 suffix and therefore making the container unable to start. That is because I pull the ubi8-image from the official repo and upload it, as it is, into my own repo with the same name. That way the image doesn't exist without the -ubi8 suffix.

Operator Information

• Operator Version: 0.11.0
• MongoDB Image used: docker.io/mongodb/mongodb-community-server:4.4.29-ubi8

Kubernetes Cluster Information

• Distribution: k3d?
• Version: v1.29.9+k3s1
• Image Registry location (quay, or an internal registry): internal

Additional context
I think the issue lies in mongodb-kubernetes-operator/controllers/construct/mongodbstatefulset.go in the function at line 367:

...

func getMongoDBImage(version string) string {
	repoUrl := os.Getenv(MongodbRepoUrl)
	imageType := envvar.GetEnvOrDefault(MongoDBImageType, DefaultImageType)

	if strings.HasSuffix(repoUrl, "/") {
		repoUrl = strings.TrimRight(repoUrl, "/")
	}
	mongoImageName := os.Getenv(MongodbImageEnv)
	for _, officialUrl := range OfficialMongodbRepoUrls {
		if repoUrl == officialUrl {
			return fmt.Sprintf("%s/%s:%s-%s", repoUrl, mongoImageName, version, imageType)
		}
	}

	// This is the old images backwards compatibility code path.
	return fmt.Sprintf("%s/%s:%s", repoUrl, mongoImageName, version)
}

...

https://github.com/mongodb/mongodb-kubernetes-operator/blob/master/controllers/construct/mongodbstatefulset.go#L367

The mongodb image gets constructed without the imageType suffix when not using one the of the official repos. I don't really understand the comment at the bottom of the function, so I can't tell if this is intentional or not.

(I removed all yaml definition stuff from the issue template here, because I don't think it is necessary in this case; If they are needed anyway, I can provide them)