Task Types

A task is one node in a DAG. kiok runs three task types; all three are authored the same way in YAML, Python, or Java.

shell

Runs an inline shell script. The script body is written to a file, made executable, and run by the Worker; stdout and stderr are captured and streamed back.

- id: extract
  type: shell
  script: |
    #!/bin/bash
    set -e
    echo "extracting"

python

Runs an inline Python script with the Worker's python3 (kiok.python.path). Useful for data manipulation without a shell wrapper.

- id: transform
  type: python
  requires: [extract]
  script: |
    print("rows:", sum(range(100)))

http

Performs an HTTP call — useful for triggering external systems or webhooks. The URL and options come from the task config:

- id: notify
  type: http
  requires: [transform]
  config:
    url: https://example.internal/webhook
    method: POST
    body: '{"status":"done"}'

Common task fields

Field	Meaning
id	Task identifier, unique within the DAG
type	shell, python, or http
script	Inline body for shell / python tasks
requires	List of upstream task ids that must succeed first
timeout	Per-task execution timeout; overrides the DAG / cluster default
config	Type-specific settings (e.g. url, method, body for http)

Referencing credentials

Task bodies must never embed secrets. Reference a stored credential indirectly — ${conn.<id>.<key>} for a connection field, ${secret.<name>} for a named secret — and kiok resolves it at execution time from the encrypted connection store. The DAG definition stays safe to commit to a public git repository.