chaostoolkit-gremlin

Gremlin, Inc support for the Chaos Toolkit.

Install

To be used from your experiment, this package must be installed in the Python environment where chaostoolkit already lives.

$ pip install chaostoolkit-gremlin

Usage

To use this package, you must create an account with Gremlin, Inc. Once registered, create a new organisation (formerly known as team). You may have to ask your Gremlin administrator to do this for you.

Once this is done, you must set the following environmental variables so the Chaos Toolkit can pick up them:

• GREMLIN_EMAIL: the email used to register to Gremlin and associated to that organisation
• GREMLIN_PWD: your password
• GREMLIN_ORG_NAME: the organisation's name you created

Note that 2FA is not yet implemented in this package.

Next you need to specify to load those variables and inject them into this package's activities. At the top of the experiment file, add the following object:

{
    "secrets": {
        "gremlin": {
            "email": {
                "type": "env",
                "key": "GREMLIN_EMAIL"
            },
            "password": {
                "type": "env",
                "key": "GREMLIN_PWD"
            },
            "org_name": {
                "type": "env",
                "key": "GREMLIN_ORG_NAME"
            }
        }
    }
}

Finally, in all activities where you call a function from this package, make sure to add the following property:

"secrets": ["gremlin"]

Here is a full example of running a CPU attack experiment:

{
    "title": "Can our system handle a node being CPU-busy?",
    "description": "CPU-usage may be impactful on our response time",
    "secrets": {
        "gremlin": {
            "email": {
                "type": "env",
                "key": "GREMLIN_EMAIL"
            },
            "password": {
                "type": "env",
                "key": "GREMLIN_PWD"
            },
            "org_name": {
                "type": "env",
                "key": "GREMLIN_ORG_NAME"
            }
        }
    },
    "method": [
        {
            "name": "attack-on-cpu",
            "type": "action",
            "background": true,
            "provider": {
                "type": "python",
                "module": "chaosgremlin.actions",
                "func": "attack",
                "secrets": ["gremlin"],
                "arguments": {
                    "command": {
                        "type": "cpu"
                    },
                    "target": {
                        "type": "Random"
                    }
                }
            }
        }
    ]
}

API Key Authentication

In order to use an API Key as your method of authentication, you'll have to set it as an environment variable: $GREMLIN_API_KEY. You can construct your experiments the same as before, but with the secrets section omitted. When secrets is not present, chaostoolkit-gremlin will grab your pre-registered Gremlin API Key and bundle it with your experiment at runtime. Here's an example of the above CPU attack, with API Key authentication:

{
    "title": "Can our system handle a node being CPU-busy?",
    "description": "CPU-usage may be impactful on our response time",
    "method": [
        {
            "name": "attack-on-cpu",
            "type": "action",
            "background": true,
            "provider": {
                "type": "python",
                "module": "chaosgremlin.actions",
                "func": "attack",
                "arguments": {
                    "command": {
                        "type": "cpu"
                    },
                    "target": {
                        "type": "Random"
                    }
                }
            }
        }
    ]
}

Note: When using API Key authentication, your Team ID must also be set as an environment variable: $GREMLIN_TEAM_ID. When using email/password authentication and you do not set a specific Team ID, the first Team ID associated with your authenticated session will be used.

Contribute

If 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.