Runner Process

Runner Process

Certified

Run tasks as local subprocesses on the worker.

Executes task commands using the host OS process APIs. The working directory is exposed as the {{workingDir}} template variable and the WORKING_DIR environment variable; input files and namespace files are materialized there before execution, and outputFiles must be written there to be captured.

When a task enables output directory support, the {{outputDir}} template variable and OUTPUT_DIR environment variable are also available as a dedicated location for output files — this is a separate mechanism from outputFiles.

Platform-agnostic (Linux/macOS/Windows). If the worker is interrupted, the process and all its descendants are killed. Kestra will re-queue the task execution when the worker restarts.

yaml
type: io.kestra.plugin.core.runner.Process

Execute a Shell command.

yaml
id: new_shell
namespace: company.team

tasks:
  - id: shell
    type: io.kestra.plugin.scripts.shell.Commands
    taskRunner:
      type: io.kestra.plugin.core.runner.Process
    commands:
      - echo "Hello World"

Install custom Python packages before executing a Python script. Note how we use the --break-system-packages flag to avoid conflicts with the system packages. Make sure to use this flag if you see errors similar to error: externally-managed-environment.

yaml
id: before_commands_example
namespace: company.team

inputs:
  - id: url
    type: URI
    defaults: https://jsonplaceholder.typicode.com/todos/1

tasks:
  - id: transform
    type: io.kestra.plugin.scripts.python.Script
    taskRunner:
      type: io.kestra.plugin.core.runner.Process
    beforeCommands:
      - pip install kestra requests --break-system-packages
    script: |
      import requests
      from kestra import Kestra

      url = "{{ inputs.url }}"

      response = requests.get(url)
      print('Status Code:', response.status_code)
      Kestra.outputs(response.json())

Pass input files to the task, execute a Shell command, then retrieve output files.

yaml
id: new_shell_with_file
namespace: company.team

inputs:
  - id: file
    type: FILE

tasks:
  - id: shell
    type: io.kestra.plugin.scripts.shell.Commands
    inputFiles:
      data.txt: "{{inputs.file}}"
    outputFiles:
      - out.txt
    taskRunner:
      type: io.kestra.plugin.core.runner.Process
    commands:
      - cp {{workingDir}}/data.txt {{workingDir}}/out.txt
Properties

Plugin Version

Defines the version of the plugin to use.

The version must follow the Semantic Versioning (SemVer) specification:

  • A single-digit MAJOR version (e.g., 1).
  • A MAJOR.MINOR version (e.g., 1.1).
  • A MAJOR.MINOR.PATCH version, optionally with any qualifier (e.g., 1.1.2, 1.1.0-SNAPSHOT).