update gcs storage solution design

[ighosh98]

Add support to allow customers to use already existing gcs buckets by leveraging existing_gcs_bucket_name and link it to Persistent Volume. In case gcs bucket isn't given as an input, we create a new one for the customer.

Testing Details

• Created gcs bucket(cluster-toolkit-gcs-test)
• Updated storage-gke.yaml to include existing bucket details

 - id: data-bucket
    source: community/modules/file-system/cloud-storage-bucket
    settings:
      local_mount: /data
      random_suffix: true
      force_destroy: true
      existing_gcs_bucket_name: "cluster-toolkit-gcs-test"

• Deployed the storage-gke blueprint
• Ran kubectl get pv. Output:

NAME                          CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                                  STORAGECLASS   VOLUMEATTRIBUTESCLASS   REASON   AGE
cluster-toolkit-gcs-test-pv   5000Gi     RWX            Retain           Bound    default/cluster-toolkit-gcs-test-pvc                  <unset>                          20m
storage-gke-01-b32ed75c-pv    1Ti        RWX            Retain           Bound    default/storage-gke-01-b32ed75c-pvc                   <unset>                          20m

• Ran kubectl describe pv cluster-toolkit-gcs-test-pv. Output:

Name:            cluster-toolkit-gcs-test-pv
Labels:          ghpc_blueprint=storage-gke
                 ghpc_deployment=storage-gke-01
                 ghpc_module=gke-persistent-volume
                 ghpc_role=file-system
Annotations:     pv.kubernetes.io/bound-by-controller: yes
Finalizers:      [kubernetes.io/pv-protection]
StorageClass:    
Status:          Bound
Claim:           default/cluster-toolkit-gcs-test-pvc
Reclaim Policy:  Retain
Access Modes:    RWX
VolumeMode:      Filesystem
Capacity:        5000Gi
Node Affinity:   <none>
Message:         
Source:
    Type:              CSI (a Container Storage Interface (CSI) volume source)
    Driver:            gcsfuse.csi.storage.gke.io
    FSType:            
    VolumeHandle:      cluster-toolkit-gcs-test
    ReadOnly:          false
    VolumeAttributes:  <none>
Events:                <none>

On provisioning without gcs_bucket. A new bucket gets created. Output of pv describe:

Name:            storage-gke-01-6960df25-pv
Labels:          ghpc_blueprint=storage-gke
                 ghpc_deployment=storage-gke-01
                 ghpc_module=gke-persistent-volume
                 ghpc_role=file-system
Annotations:     pv.kubernetes.io/bound-by-controller: yes
Finalizers:      [kubernetes.io/pv-protection]
StorageClass:    
Status:          Bound
Claim:           default/storage-gke-01-6960df25-pvc
Reclaim Policy:  Retain
Access Modes:    RWX
VolumeMode:      Filesystem
Capacity:        5000Gi
Node Affinity:   <none>
Message:         
Source:
    Type:              CSI (a Container Storage Interface (CSI) volume source)
    Driver:            gcsfuse.csi.storage.gke.io
    FSType:            
    VolumeHandle:      storage-gke-01-6960df25
    ReadOnly:          false
    VolumeAttributes:  <none>
Events:                <none>

[ankitkinra]

Still debating whether this is the right strategy or instead should we have a different module with only option to import a gcs bucket rather than reusing this module.