Managing Directories

  • This example uses a k8s directory.

    • Inside are the following yaml files:

      • api-depl.yaml
      • api-service.yaml
      • db-depl.yaml
      • db-service.yaml

  • We can manage Kubernetes manifests spread across multiple directories.

  • Usually we go into the k8s directory and run a kubectl apply to the manifests there.

  • For example, over time the amount of yaml files grows.

  • Over time however, we move yaml files into sub directories. For example all of the db files go into the db directory and api files go into the api directory.

  • To deploy manifests in particular directories, you would use the below command as an example: 
    kubectl apply -f k8s/api/
kubectl apply -f k8s/db/

  • Every time we apply or delete configs, we’d have to run the above commands in each directory and the CI/CD pipelines become murky.

  • Therefore a good way is to add a kustomization.yaml file just under the k8s directory.

  • The kustomization.yaml file would look like the following in this example: ``` apiVersion: kustomize.config.k8s.io/v1beta1 kind: Kustomization

kubernetes resources to be managed by kustomize

resources:

  • api/api-depl.yaml
  • api/api-service.yaml
  • db/db-depl.yaml

  • db/db-service.yaml ```

  • Now kustomize is aware and we’d just need to run this command: 
    kustomize build k8s/ | kubectl apply -f -
    • We run the above in the root of the k8s directory.

  • Can apply this natively with Kubernetes using kubectl apply -k k8s

  • What happens if the amount of directories grows - we now have a cache directory as well as a kafka directory.

    • That means all of the kustomization resources will be pulled in from the above directories.

      • Can also add a kustomization.yaml file within each of the sub-directories. The configs will only be imported for that single directory.

        • Within the sub-directory kustomization.yaml files, we add the following:
  • Example below for the db directory:
k8s/db/kustomization.yaml

resources:
  - db-depl.yaml
  - db-service.yaml
  • Then in the root k8s directory, you would have (each of the above directories listed) ``` resources:
    • api/
    • db/
    • cache/

    • kafka/ ```

    • It will go into the sub-directory and look for a kustomization.yaml file.

  • Keeps everything clean and neat.

  • Then as before, to apply the manifests: ``` kustomize build k8s/ | kutcle apply -f -
or

kubectl apply -k k8s/ ```

Updated: