Manage a workload using a YAML file

This topic tells you how to use the Tanzu Apps CLI to manage a workload using a yaml file.

Changing clusters

The Tanzu Apps CLI refers to the default kubeconfig file to access a Kubernetes cluster. When a tanzu apps command is run, the Tanzu Apps CLI uses the default context that is defined in that kubeconfig file (located by default at $HOME/.kube/config).

There are two ways to change the target cluster:

Use kubectl config use-context <context-name> to change the default context. All subsequent tanzu apps commands target the cluster defined in the new default kubeconfig context.
Include the --context <context-name> flag when running any tanzu apps command. All subsequent tanzu apps commands without the --context <context-name> flag continues to use the default context set in the kubeconfig.

There are also two ways to override the default kubeconfig:

Set the environment KUBECONFIG=<path> to change the kubeconfig the Apps CLI plug-in references. All subsequent tanzu apps commands reference the non-default kubeconfig assigned to the environment.
Include the --kubeconfig <path> flag when running any tanzu apps command. All subsequent tanzu apps commands without the --kubeconfig <path> flag continues to use the default kubeconfig.

For more information about kubeconfig, see Configure Access to Multiple Clusters Kubernetes documentation.

Checking update status

You can use the Tanzu Apps CLI to create or update a workload. After you’ve submitted your changes to the platform, the CLI command exits. Depending on the changes you submitted, it might take time for them to be executed on the platform. Run tanzu apps workload get to verify the status of your changes. For more information about this command, see Tanzu Apps Workload Get.

Working with YAML files

In many cases, you can manage workload life cycles through CLI commands. However, you might find cases where you want to manage a workload by using a yaml file. The Tanzu Apps CLI supports using yaml files.

The Tanzu Apps CLI manages one workload at a time. When you manage a workload using a yaml file, that file must contain a single workload definition. Tanzu Apps CLI commands support only one file per command.

For example:

---
apiVersion: carto.run/v1alpha1
kind: Workload
metadata:
  name: tanzu-java-web-app
  labels:
    app.kubernetes.io/part-of: tanzu-java-web-app
    apps.tanzu.vmware.com/workload-type: web
spec:
  source:
    git:
      url: https://github.com/vmware-tanzu/application-accelerator-samples
      ref:
        tag: tap-1.3
    subPath: tanzu-java-web-app

To create a workload from a file like the previous one, run:

tanzu apps workload create -f my-workload-file.yaml

Another way to create a workload from yaml is passing the definition through stdin. For example, run:

tanzu apps workload create -f - --yes

The console waits for input, and the content with a valid yaml definition for a workload is either written or pasted. Then click ctrl+D three times to start workload creation. This can also be done with workload update and workload apply commands.

Note to pass workload through stdin, --yes flag is needed. If not used, command fails.

Autocompletion

To enable command autocompletion, the Tanzu CLI offers the tanzu completion command.

Run:

Bash

tanzu completion bash >  $HOME/.tanzu/completion.bash.inc

Zsh

echo "autoload -U compinit; compinit" >> ~/.zshrc
tanzu completion zsh > "${fpath[1]}/_tanzu"