* Superset
** Required software
  - Helm: v3.13.2-linux-amd64
  - Kubernetes ($ kubectl version):
    - Client Version: v1.28.4
    - Kustomize Version: v5.0.4-0.20230601165947-6ce0bf390ce3
    - Server Version: v1.28.4
  - OS: Red Hat Enterprise Linux Server release 7.9 (Maipo)
    - Kernel: 3.10.0-1160.102.1.el7.x86_64
  - Helm charts:
    - superset-0.10.15
    - redis-17.9.4
    - postgresql-12.1.6
  - Superset (installed using Helm chart): 2.1.2
  - PostgreSQL (installed using Helm chart): 14.6.0
  - Redis (installed using Helm chart): redis: 7.0.10

** Networking
   - Service port accessible on the node: 3054

** Prerequisites
   1. In Kubernetes, local-storage storage class should be default. If
      it isn't then PVs may not bind to the PVC. To fix this, run:
      $ kubectl patch storageclass local-storage -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'

** Template generation using Helm
   1. helm repo add superset https://apache.github.io/superset
   2. kubectl create namespace superset
   3. helm -n superset show values superset/superset > values_orig.yaml
   4. If the file values.yaml doesn't exist:
      - cp -n values_orig.yaml values.yaml
   5. Modify values.yaml for required configuration.
      - To see the configuration differences between the original and
        the modified version of values.yaml, do:
        $ diff -u values_orig.yaml values.yaml
   6. helm template --name-template=superset -f values.yaml -n superset superset superset/superset > superset_template_orig.yaml
   7. In the current setup, superset_template_orig.yaml is templatized into
      superset_template.yaml.j2 by modifying certain variables. See
      constants.in for variables that have been templatized.
      - Variables inside superset_template.yaml.j2 are replaced
        with values stored inside `constants.in` and
        `../global-constants.in` files, and then saved into
        superset_template.yaml by running the ./setup_template.sh script.
      - To view the differences between the original template
        (superset_template_orig.yaml) and the generated template
        (superset_template.yaml) run the script using the
        `online` argument:
        $ ./setup_template.sh online
   8. Edit superset_volume.yaml.j2 for modifying the Persistent Volume
      (PV) properties for Superset, and constants.in for modifying the
      size and host path.

** Install Superset on Kubernetes
   1. mkdir -p /var/superset/postgresql
   2. Copy all the files from 'superset' directory.
   3. Upload the following images to the local private container
      registry:
      1. apache/superset:dockerize
      2. apache/superset:2.1.2
      3. docker.io/bitnami/postgresql:14.6.0-debian-11-r13
      4. docker.io/bitnami/redis:7.0.10-debian-11-r4
   4. Make sure global-constants.in contains correct information for
      the following variables:
      1. LOCAL_REGISTRY: Put in the correct URL of local container
         registry for offline installation (client-side).
      2. LOCAL_DOWNLOAD_REPO: Put in the correct URL of the local
         download file server for offline installation
         (client-side).
      3. For online (ec2) installation do not change these two variables.
      4. Run setup_template.sh:
         - If on client-side, run: `./setup_template.sh offline`
         - If on EC2 server, run: `./setup_template.sh online`
      5. kubectl create namespace superset
      6. kubectl -n superset apply -f superset_template.yaml
      7. kubectl apply -f superset_volume.yaml