almanach/doc/source/index.rst

Welcome to the Almanach documentation!

Almanach stores the utilization of OpenStack resources (instances and volumes) for each tenant.

What is Almanach?

The main purpose of this software is to bill customers based on their usage of the cloud infrastructure.

Almanach is composed of two parts:

• Collector: Listen for OpenStack events and store the relevant information in the database.
• REST API: Expose the information collected to external systems.

Requirements

• OpenStack infrastructure installed (Nova, Cinder...)
• MongoDB
• Python 2.7

Command line usage

Usage:

usage: almanach [-h] [--logging LOGGING] {api,collector} config_file

Start the API daemon:

almanach api /path/to/almanach.cfg

Start the collector:

almanach collector /path/to/almanach.cfg

Custom logging configuration:

almanach collector /path/to/almanach.cfg --logging /path/to/logging.cfg

The syntax of the logging configuration file is available in the official [Python documentation](https://docs.python.org/2/library/logging.config.html).

Authentication

Protocol

The authentication mechanism use the HTTP header X-Auth-Token to send a token. This token is validated through Keystone or with the config file (private secret key).

GET /volume_types HTTP/1.1
X-Auth-Token: secret
Content-Type: application/json

{}

If the token is not valid, you will receive a 401 Not Authorized response.

Private Key Authentication

The private secret key authentication is the default method. In your config file, you have to define your private key in the field auth_token:

[ALMANACH]
auth_token=my secret token

Keystone Authentication

The token will be validated with Keystone. To use this authentication backend you have to define the authentication strategy to keystone.

[ALMANACH]
auth_strategy=keystone

[KEYSTONE]
username=my_service_username
password=my_service_password
tenant_name=my_service_tenant_name
auth_url=http://keystone_url:5000/v2.0

Environment variables

You can override the configuration parameters by using environment variables:

export RABBITMQ_URL="amqp://openstack:openstack@hostname:5672"
almanach collector /path/to/almanach.cfg

Running Almanach with Docker

The actual Docker configuration assume that you already have RabbitMQ (mandatory for Openstack) and MongoDB configured for Almanach.

export RABBITMQ_URL="amqp://guest:guest@messaging:5672/"
export MONGODB_URL="mongodb://almanach:almanach@database:27017/almanach"

docker-compose build
docker-compose up

The command docker-compose up starts 2 containers: the collector and the API server. The environment variables RABBITMQ_URL and MONGODB_URL are mandatory.

RabbitMQ configuration

Each OpenStack services (Nova, Cinder, Neutron) need to be configured to send notifications to the Almanach queue.

For example with Nova, add the topic "almanach" in the config file /etc/nova.conf:

notification_topics=almanach

Database configuration

Almanach requires a specific user to connect to the database. To create a new user, open a new MongoDB shell:

m = new Mongo()
m.getDB("almanach").createUser({user: "almanach", pwd: "almanach", roles: [{role: "readWrite", db: "almanach"}]})

Devstack configuration

[[local|localrc]]
ADMIN_PASSWORD=secret
DATABASE_PASSWORD=$ADMIN_PASSWORD
RABBIT_PASSWORD=$ADMIN_PASSWORD
SERVICE_PASSWORD=$ADMIN_PASSWORD

enable_plugin almanach https://git.openstack.org/openstack/almanach

[[post-config|$NOVA_CONF]]
[DEFAULT]
notification_topics=almanach,notifications

[[post-config|$CINDER_CONF]]
[DEFAULT]
notification_topics=almanach,notifications

Database entities

Each entity have at least these properties:

• entity_id: Unique id for the entity (UUID)
• entity_type: "instance" or "volume"
• project_id: Tenant unique ID (UUID)
• start: Start date of the resource usage
• end: End date of the resource usage or null if the resource still in use by the tenant
• name: Resource name

Compute Object

{
    "entity_id": "UUID",
    "entity_type": "instance",
    "project_id": "UUID",
    "start": "2014-01-01T06:00:00.000Z",
    "end": null,
    "last_event": "2014-01-01T06:00:00.000Z",
    "flavor": "MyFlavor1",
    "os": {
        "distro": "ubuntu",
        "version": "14.04"
    },
    "name": "my-virtual-machine.domain.tld"
}

Block Storage Object

{
    "entity_id": "UUID",
    "entity_type": "volume",
    "project_id": "UUID",
    "start": "2014-01-01T06:00:00.000Z",
    "end": null,
    "last_event": "2014-01-01T06:00:00.000Z",
    "volume_type": "MyVolumeType",
    "size": 50,
    "name": "my-virtual-machine.domain.tld-volume",
    "attached_to": "UUID"
}

List of events handled

Almanach will process those events:

• compute.instance.create.end
• compute.instance.delete.end
• compute.instance.resize.confirm.end
• compute.instance.rebuild.end
• volume.create.end
• volume.delete.end
• volume.resize.end
• volume.attach.end
• volume.detach.end
• volume.update.end
• volume.exists
• volume_type.create

API documentation

almanach.api:app