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Usage¶

Docker Scaler is controlled by sending HTTP requests to [SCALER_IP]:[SCALER_PORT]

Scaling Services¶

Scaling Services - Alertmanager Webhook¶

This request queries docker service labels: com.df.scaleMin, com.df.scaleMax, com.df.scaleDownBy, com.df.scaleUpBy to determine how much to scale the service by. The request body conforms to the alertmanager notifications so that Docker Scaler can be used as a webhook.

URL: /v1/scale-service
Method: POST
Request Body:

{
    "groupLabels": {
        "scale": "up",
        "service": "example_web"
    }
}

The service value is the name of the service to scale. The scale value accepts up for scaling up and down for scaling down.

Service Label	Description
`com.df.scaleMin`	Minimum number of replicas
`com.df.scaleMax`	Maximum number of replicas
`com.df.scaleDownBy`	Number of replicas to scale down by
`com.df.scaleUpBy`	Number of replicas to scale up by

Scaling Services - User Friendly Endpoint¶

The whole scaling event can be place in the url:

URL: /v1/scale-service
Method: POST
Query Parameters:

Query	Description	Required
service	Name of service to reschedule	yes
scale	Direction to scale (`up` or `down`)	yes
by	Number of replicas to scale by	yes

The com.df.scaleMax and com.df.scaleMin will still be used to bound the number of replicas for the service.

Rescheduling All Services¶

This request only reschedule services with label: com.df.reschedule=true. See Configuration to change this default.

URL: /v1/reschedule-services
Method: POST

Rescheduling One Service¶

This request only reschedule target service with label: com.df.reschedule=true. See Configuration to change this default.

URL: /v1/reschedule-service
Method: POST
Query Parameters:

Query	Description	Required
service	Name of service to reschedule	yes

Scaling Nodes¶

The node scaling feature is activated by setting NODE_SCALER_BACKEND to a backend.

Scaling Nodes - AlertManager Webhook¶

The request body conforms to the alertmanager notifications so that Docker Scaler can be used as a webhook.

URL: /v1/scale-nodes
Method: POST
Request Body:

{
    "groupLabels": {
        "scale": "down",
        "service": "node_exporter",
    }
}

The scale value accepts up for scaling up and down for scaling down. When Docker Scaler it setup to send the service name that trigger the alert, the service parameter can be passed on to Docker Scaler as a group label. Docker Scaler will use the following labels on the service to configure how to scale nodes:

Service Label	Description
`com.df.scaleManagerNodeMin`	Minimum number of managers
`com.df.scaleManagerNodeMax`	Maximum number of managers
`com.df.scaleManagerNodeDownBy`	Number of nodes to scale managers down by
`com.df.scaleManagerNodeUpBy`	Number of nodes to scale managers up by
`com.df.scaleWorkerNodeMin`	Minimum number of workers
`com.df.scaleWorkerNodeMax`	Maximum number of workers
`com.df.scaleWorkerNodeDownBy`	Number of nodes to scale workers down by
`com.df.scaleWorkerNodeUpBy`	Number of nodes to scale workers up by

Scaling Nodes - User Friendly Endpoint¶

The whole node scaling event can be place in the url:

URL: /v1/scale-nodes
Method: POST
Query Parameters:

Query	Description	Required
by	The number of nodes to scale up or down by	yes
scale	Direction to scale (`up` or `down`)	yes
type	Type of node to scale (`manager` or `worker`)	yes