Remove Hardcoded `kube-system` Namespace for `ingress-uid` ConfigMap

[vishalanarase]

Description:

Currently, the Ingress Controller stores the ingress-uid ConfigMap in the kube-system namespace by default. This behavior is hardcoded, limiting deployment flexibility and namespace isolation.

To align with best practices and enhance controller deployment flexibility, the namespace for ingress-uid should be configurable based on the namespace where the controller is running or explicitly provided via a flag (e.g., --ingress-configmap-namespace).

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Current Behavior:

• ingress-uid ConfigMap is always created in the kube-system namespace, even if the controller is running in a different namespace.

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Expected Behavior:

• The ingress-uid ConfigMap should be created in the namespace where the controller is running.
• Alternatively, provide a flag such as --ingress-configmap-namespace to override the namespace.
• If not specified, the controller's own namespace should be the default.

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Proposed Solution:

1. Introduce a flag:

   --ingress-configmap-namespace=<namespace>

2. Fallback logic:

   • If the flag is not set, default to the controller's namespace (POD_NAMESPACE).
   • If that is not set, fallback to kube-system.

3. Controller logic change (I'm assuming, It's doing something like):
   Replace hardcoded namespace in:

   client.CoreV1().ConfigMaps("kube-system").Create(...)

   With:

   namespace := os.Getenv("POD_NAMESPACE")
   if namespace == "" {
       namespace = "kube-system"
   }
   client.CoreV1().ConfigMaps(namespace).Create(...)

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Impact:

• Enhanced flexibility for running the controller in different namespaces.
• Better alignment with namespace isolation and multi-tenant Kubernetes clusters.

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