Skip to content

The chaos init command

You use the chaos init command to take a discovery report, usually created by the chaos discover command, to then create an experiment based upon what has been discovered about the integration extension and, if applicable, the target environment.

You can see the options available to you by executing:

chaos init --help
Usage: chaos init [OPTIONS]

  Initialize a new experiment from discovered capabilities.

Options:
  --discovery-path PATH   Path to the discovery outcome.  [default:
                          ./discovery.json]
  --experiment-path PATH  Path where to save the experiment (.yaml or .json)
                          [default: ./experiment.json]
  --help                  Show this message and exit.

A tutorial on how to use the chaos init command is available as part of the Chaos Toolkit’s Getting Started tutorials.

Initialise a new experiment

To initialise a new experiment based on what has been discovered you simply need to execute the chaos init command:

chaos init
The following is a capture of the output after running chaos init and following the interactive prompts: [2018-01-30 15:54:50 INFO] Let's build a new experiment Experiment's title: My new experiment Add an activity to your method Activity (0 to escape): 1 Kill a microservice by `name` in the namespace `ns`. The microservice is killed by deleting the deployment for it without a graceful period to trigger an abrupt termination. The selected resources are matched by the given `label_selector`. Do you want to use this action? [y/N]: y Argument's value for 'name': Argument's value for 'ns' [default]: Argument's value for 'label_selector' [name in ({name})]: app=webapp-app Do you want to select another activity? [y/N]: N [2018-01-30 15:55:21 INFO] Experiment created and saved in './experiment.json'

By default, the chaos init command will look for a ./discovery.json file and use that as the basis of a new experiment’s initialisation.

You can specify another file to be used by suppling the --discovery-report-path option.

In addition the default output from the init command will be a new Chaos Toolkit experiment definition in a ./experiment.json file. If you would prefer a different filename then this can be specified using the --experiment-path option.