Write Keptn Tasks

Keptn Task Definition

A KeptnTaskDefinition is a CRD used to define tasks that can be run by the Keptn Lifecycle Toolkit as part of pre- and post-deployment phases of a deployment. The task definition is a Deno script. In the future, we also intend to support other runtimes, especially running a container image directly.

A task definition can be configured in three different ways:

• inline
• referring to an HTTP script
• referring to another KeptnTaskDefinition

An inline task definition looks like the following:

apiVersion: lifecycle.keptn.sh/v1alpha2
kind: KeptnTaskDefinition
metadata:
  name: deployment-hello
spec:
  function:
    inline:
      code: |
        console.log("Deployment Task has been executed");        

In the code section, it is possible to define a full-fletched Deno script.

The runtime can also fetch the script on the fly from a remote webserver. For this, the CRD should look like the following:

apiVersion: lifecycle.keptn.sh/v1alpha2
kind: KeptnTaskDefinition
metadata:
  name: hello-keptn-http
spec:
  function:
    httpRef:
      url: <url>

Finally, KeptnTaskDefinition can build on top of other KeptnTaskDefinitions. This is a common use case where a general function can be re-used in multiple places with different parameters.

apiVersion: lifecycle.keptn.sh/v1alpha2
kind: KeptnTaskDefinition
metadata:
  name: slack-notification-dev
spec:
  function:
    functionRef:
      name: slack-notification
    parameters:
      map:
        textMessage: "This is my configuration"
    secureParameters:
      secret: slack-token

As you might have noticed, Task Definitions also have the possibility to use input parameters. The Lifecycle Toolkit passes the values defined inside the map field as a JSON object. At the moment, multi-level maps are not supported. The JSON object can be read through the environment variable DATA using Deno.env.get("DATA");. Kubernetes secrets can also be passed to the function using the secureParameters field. Here, the secret value is the K8s secret name that will be mounted into the runtime and made available to the function via the environment variable SECURE_DATA.