This project is a collection of actions and probes, gathered as an extension to the Chaos Toolkit.
Please NOTE This extension is in the early stages of development. Please feel free to create an issue in case of needed ehancement or misfunctioning.
This package requires Python 3.6+
To be used from your experiment, this package must be installed in the Python environment where chaostoolkit already lives.
$ pip install -U chaostoolkit-ansible
This chaos toolkit driver provides you an easy way to execute probe and/or actions using ansible modules. By using it, you can execute tasks, gather facts, ... on remote systems
To use the probes from this package, add the following to your experiment file:
In JSON:
"steady-state-hypothesis": {
"title": "Tests",
"probes": [
{
"type": "probe",
"name": "test-current-directory",
"tolerance": {
"type": "jsonpath",
"path": "$.*.task",
"expect": "/home/me"
},
"provider": {
"type": "python",
"module": "chaosansible.probes",
"func": "chaosansible_probe",
"arguments": {
"host_list": ["myserver1", "myserver2"],
"facts": "yes",
"ansible": {
"module": "shell",
"args": "pwd"
}
}
}
}
]
}In YAML:
---
steady-state-hypothesis:
title: The current working directory must be /home/me
probes:
- type: probe
name: test-current-directory
tolerance:
type: jsonpath
target: "$.*.task"
pattern: /home/me
provider:
type: python
module: chaosansible.probes
func: chaosansible_probe
arguments:
host_list: ["myserver1", "myserver2"]
facts: True
ansible:
module: shell
args: pwdThat's it!
Probes can be gathered by using the stdout of an ansible task or through the ansible gather_facts module. Each time chaostoolkit-ansible runs, it returns a json that can be used in tolerance (using jsonpath, regex, ...)
This json is always formatted the same way (Exemple for a two targets host_list):
{
"target1": {
"fact": " -> JSON result of the ansible gather_facts",
"task": " -> String result containing the stdout value of the task result - Empty when ansible task do not return stdout"
},
"target2": {
"fact": "...",
"task": "..."
}
}To use the actions from this package, add the following to your experiment file:
In JSON:
"method": [
{
"type": "action",
"name": "delete-etc-hosts-file",
"provider": {
"type": "python",
"module": "chaosansible.actions",
"func": "chaosansible_run",
"arguments": {
"host_list": ["server1", "server2"],
"become": true,
"ansible": {
"module": "file",
"args": {
"path": "/etc/hosts",
"state": "absent"
}
}
}
}
}
]In YAML:
---
method:
- type: action
name: delete-etc-hosts-file
provider:
type: python
module: chaosansible.actions
func: chaosansible_run
arguments:
host_list: ["server1", "server2"]
become: True
ansible:
module: file
args:
path: /etc/hosts
state: absentThe configuration block can be used to specify specific parameters to use. This block can be omit unless you really need to change default ansible parameters to run your exeperiment
Configuration variables that can be used by this driver are:
- ansible_module_path: Path of your ansible library
- ansible_become_user: Privileged user used when you call privilege escalation (root by default)
- ansible_ssh_private_key: Your ssh private key used to connect to targets (~/.ssh/id_rsa by default)
- ansible_user: User on target host used by ansible (current username by default)
- become_ask_pass: Password to escalate privileged when sudo needs one
- ansible_extra_ssh_args: SSH extra args
In case you need to change one/or many default configuration(s), you can specify your value using the configuration block
Please feel free to ask, if you need access to other ansible configuration parameters
In JSON:
"configuration": {
"ansible_ssh_private_key": "/home/me/.ssh/mykey"
}In YAML:
configuration:
ansible_ssh_private_key: "/home/me/.ssh/mykey"chaosansible_run and chaosansible_probes use arguements (Most argument are classical ansible parameters):
| Argument | Type | Required | Default value | Description |
|---|---|---|---|---|
| host_list | Array | localhost | List of host to use | |
| facts | bool | false | Gather_facts | |
| become | bool | false | Escalate privilege to run task | |
| run_once | bool | false | Run the task only once on one target | |
| num_target | str | all | "all" or "x" where x is an integer. Run the task to only x target among the host_list. Ideal to create random event | |
| ansible | dict | {} | Execute ansible task. Cf ansible dict format. If ansible is not set, no task except ansible gather_facts (if facts set to True) |
Ansible dict format:
Classic ansible task are in the form:
name: task name
ansible-module-name:
module-parameter1: value1
module-parameter2: value2This is translate into chaos experiment file like this: In JSON
"ansible": {
"module": "ansible-module-name",
"args": {
"module-parameter1": "value1",
"module-parameter2": "value2"
}
}In YAML
ansible:
module: ansible-module-name
args:
module-parameter1: value1
module-parameter2: value2Example with the ansible mount module (Umount a filesystem):
In JSON
"ansible": {
"module": "mount",
"args": {
"path": "/data",
"state": "unmounted"
}
}In YAML
ansible:
module: mount
args:
path: /data
state: unmountedIn JSON
"method": [
{
"type": "action",
"name": "delete-etc-hosts-file",
"provider": {
"type": "python",
"module": "chaosansible.actions",
"func": "chaosansible_run",
"arguments": {
"host_list": ["server1","server2","server3","server4","server5"],
"num_target": "2",
"become": true,
"ansible": {
"module": "file",
"args": {
"path": "/etc/hosts",
"state": "absent"
}
}
}
}
}
]In YAML
method:
- type: action
name: delete-etc-hosts-file
provider:
type: python
module: chaosansible.actions
func: chaosansible_run
arguments:
host_list: ["server1","server2","server3","server4","server5"]
become: True
num_target: "2"
ansible:
module: file
args:
path: /etc/hosts
state: absentIn JSON
"method": [
{
"type": "action",
"name": "delete-etc-hosts-file",
"provider": {
"type": "python",
"module": "chaosansible.actions",
"func": "chaosansible_run",
"arguments": {
"host_list": ["server1","server2","server3","server4","server5"],
"num_target": "3",
"ansible": {
"module": "shell",
"args": {
"cmd": "stress-ng --cpu 0 --cpu-method matrixprod -t 60s",
}
}
}
}
}
]In YAML
method:
- type: action
name: delete-etc-hosts-file
provider:
type: python
module: chaosansible.actions
func: chaosansible_run
arguments:
host_list: ["server1","server2","server3","server4","server5"]
become: True
num_target: "3"
ansible:
module: shell
args:
cmd: stress-ng --cpu 0 --cpu-method matrixprod -t 60sIf you wish to contribute more functions to this package, you are more than welcome to do so. Please, fork this project, make your changes following the usual PEP 8 code style, sprinkling with tests and submit a PR for review.
The Chaos Toolkit projects require all contributors must sign a Developer Certificate of Origin on each commit they would like to merge into the master branch of the repository. Please, make sure you can abide by the rules of the DCO before submitting a PR.
If you wish to develop on this project, make sure to install the development dependencies. But first, create a virtual environment and then install those dependencies.
$ pip install -r requirements-dev.txt -r requirements.txtThen, point your environment to this directory:
$ pip install -e .Now, you can edit the files and they will be automatically be seen by your
environment, even when running from the chaos command locally.
To run the tests for the project execute the following:
$ pytest