kouneli

Kubernetes autoscaler based on rabbit queue length written in node.

Configuration

Queues

To set the queues to be watched and the resources to be scaled you have these variables:

• queue: name of the queue to watched
• minCount: minimun number of the resource that need to be deployed always
• maxCount: maximun number of the resource kouneli will scale to
• maxNew: maximun number of new resources kouneli will create when scaling up
• interval: time interval in seconds between kouneli checks the queue status
• namespace: namespace where the resource is deployed
• targetKind: kind of the resource (at this momment only Deployment is allowed)
• targetName: name of the deployed resource

You can configure kouneli using two different methods (both can work at the same time):

• Setting a config.json file. You can find an example at config.json.example. The downside of this method is that you will have to build the image each time you want to change the configuration.

• Setting the environment variable named CONFIG. You can find an example at autoscaler-deployment.yaml. You can use ; as separator of different queues config and | as separator of each queue config parameters. The sintaxis is the following:

queue|minCount|maxCount|maxNew|interval|namespace|targetKind|targetName

The downside of this method is that you cannot watch queues with | or ; in its names.

K8s

If you are deploying kouneli in the same cluster as the resources you want to watch, you have to set the environment variable INCLUSTER to true. Otherwise kouneli will take the configuration from your kubeconfig file.

Rabbit

To configure rabbit connection you can use these variables:

• KUBERNETES_RABBITMQ_SERVICE_NAME: name of the rabbitmq service if you have it deployed in the same cluster as kouneli
• RABBITMQ_HOST: hostname for rabbitmq

NOTE: you can provide one of these. If you provide both, RABBITMQ_HOST will prevail over KUBERNETES_RABBITMQ_SERVICE_NAME. If you provide none, the defalt value is localhost

• RABBITMQ_PORT: port for rabbitmq admin (default: 15672)
• RABBITMQ_USER: user for rabbitmq
• RABBITMQ_PASS: password for rabbitmq