digitalocean

README

Cluster Autoscaler for DigitalOcean

The cluster autoscaler for DigitalOcean scales worker nodes within any specified DigitalOcean Kubernetes cluster's node pool. This is part of the DOKS offering which can be enabled/disable dynamically for an existing cluster.

Configuration

Cloud config file

The (JSON) configuration file of the DigitalOcean cloud provider supports the following values:

• cluster_id: the ID of the cluster (a UUID)
• token: the DigitalOcean access token literally defined
• token_file: a file path containing the DigitalOcean access token
• url: the DigitalOcean URL (optional; defaults to https://api.digitalocean.com/)

Exactly one of token or token_file must be provided.

Behavior

Parameters of the autoscaler (such as whether it is on or off, and the minimum/maximum values) are configured through the public DOKS API and subsequently reflected by the node pool objects. The cloud provider periodically picks up the configuration from the API and adjusts the behavior accordingly.

Development

Make sure you're inside the root path of the autoscaler repository

1.) Build the cluster-autoscaler binary:

make build-in-docker

2.) Build the docker image:

docker build -t digitalocean/cluster-autoscaler:dev .

3.) Push the docker image to Docker hub:

docker push digitalocean/cluster-autoscaler:dev

Documentation

Index

• Constants
• Variables
• func BuildDigitalOcean(opts config.AutoscalingOptions, do cloudprovider.NodeGroupDiscoveryOptions, ...) cloudprovider.CloudProvider
• type Config
• type Manager
  • func (m *Manager) Refresh() error
• type NodeGroup
  • func (n *NodeGroup) AtomicIncreaseSize(delta int) error
  • func (n *NodeGroup) Autoprovisioned() bool
  • func (n *NodeGroup) Create() (cloudprovider.NodeGroup, error)
  • func (n *NodeGroup) Debug() string
  • func (n *NodeGroup) DecreaseTargetSize(delta int) error
  • func (n *NodeGroup) Delete() error
  • func (n *NodeGroup) DeleteNodes(nodes []*apiv1.Node) error
  • func (n *NodeGroup) Exist() bool
  • func (n *NodeGroup) ForceDeleteNodes(nodes []*apiv1.Node) error
  • func (n *NodeGroup) GetOptions(defaults config.NodeGroupAutoscalingOptions) (*config.NodeGroupAutoscalingOptions, error)
  • func (n *NodeGroup) Id() string
  • func (n *NodeGroup) IncreaseSize(delta int) error
  • func (n *NodeGroup) MaxSize() int
  • func (n *NodeGroup) MinSize() int
  • func (n *NodeGroup) Nodes() ([]cloudprovider.Instance, error)
  • func (n *NodeGroup) TargetSize() (int, error)
  • func (n *NodeGroup) TemplateNodeInfo() (*framework.NodeInfo, error)

Constants

const (
	// GPULabel is the label added to nodes with GPU resource.
	GPULabel = "cloud.digitalocean.com/gpu-node"
)

Variables

var (
	// ErrNodePoolNotExist is return if no node pool exists for a given cluster ID
	ErrNodePoolNotExist = errors.New("node pool does not exist")
)

Functions

func BuildDigitalOcean

func BuildDigitalOcean(
	opts config.AutoscalingOptions,
	do cloudprovider.NodeGroupDiscoveryOptions,
	rl *cloudprovider.ResourceLimiter,
) cloudprovider.CloudProvider

BuildDigitalOcean builds the DigitalOcean cloud provider.

Types

type Config

type Config struct {
	// ClusterID is the id associated with the cluster where DigitalOcean
	// Cluster Autoscaler is running.
	ClusterID string `json:"cluster_id"`

	// Token is the User's Access Token associated with the cluster where
	// DigitalOcean Cluster Autoscaler is running.
	Token string `json:"token"`

	// TokenFile references the token from the given file. It cannot be specified
	// together with Token.
	TokenFile string `json:"token_file"`

	// URL points to DigitalOcean API. If empty, defaults to
	// https://api.digitalocean.com/
	URL string `json:"url"`
}

Config is the configuration of the DigitalOcean cloud provider

type Manager

type Manager struct {
	// contains filtered or unexported fields
}

Manager handles DigitalOcean communication and data caching of node groups (node pools in DOKS)

func (*Manager) Refresh

func (m *Manager) Refresh() error

Refresh refreshes the cache holding the nodegroups. This is called by the CA based on the `--scan-interval`. By default it's 10 seconds.

type NodeGroup

type NodeGroup struct {
	// contains filtered or unexported fields
}

NodeGroup implements cloudprovider.NodeGroup interface. NodeGroup contains configuration info and functions to control a set of nodes that have the same capacity and set of labels.

func (*NodeGroup) AtomicIncreaseSize

func (n *NodeGroup) AtomicIncreaseSize(delta int) error

AtomicIncreaseSize is not implemented.

func (*NodeGroup) Autoprovisioned

func (n *NodeGroup) Autoprovisioned() bool

Autoprovisioned returns true if the node group is autoprovisioned. An autoprovisioned group was created by CA and can be deleted when scaled to 0.

func (*NodeGroup) Create

func (n *NodeGroup) Create() (cloudprovider.NodeGroup, error)

Create creates the node group on the cloud provider side. Implementation optional.

func (*NodeGroup) Debug

func (n *NodeGroup) Debug() string

Debug returns a string containing all information regarding this node group.

func (*NodeGroup) DecreaseTargetSize

func (n *NodeGroup) DecreaseTargetSize(delta int) error

DecreaseTargetSize decreases the target size of the node group. This function doesn't permit to delete any existing node and can be used only to reduce the request for new nodes that have not been yet fulfilled. Delta should be negative. It is assumed that cloud provider will not delete the existing nodes when there is an option to just decrease the target. Implementation required.

func (*NodeGroup) Delete

func (n *NodeGroup) Delete() error

Delete deletes the node group on the cloud provider side. This will be executed only for autoprovisioned node groups, once their size drops to 0. Implementation optional.

func (*NodeGroup) DeleteNodes

func (n *NodeGroup) DeleteNodes(nodes []*apiv1.Node) error

DeleteNodes deletes nodes from this node group (and also increasing the size of the node group with that). Error is returned either on failure or if the given node doesn't belong to this node group. This function should wait until node group size is updated. Implementation required.

func (*NodeGroup) Exist

func (n *NodeGroup) Exist() bool

Exist checks if the node group really exists on the cloud provider side. Allows to tell the theoretical node group from the real one. Implementation required.

func (*NodeGroup) ForceDeleteNodes

func (n *NodeGroup) ForceDeleteNodes(nodes []*apiv1.Node) error

ForceDeleteNodes deletes nodes from the group regardless of constraints.

func (*NodeGroup) GetOptions

func (n *NodeGroup) GetOptions(defaults config.NodeGroupAutoscalingOptions) (*config.NodeGroupAutoscalingOptions, error)

GetOptions returns NodeGroupAutoscalingOptions that should be used for this particular NodeGroup. Returning a nil will result in using default options.

func (*NodeGroup) Id

func (n *NodeGroup) Id() string

Id returns an unique identifier of the node group.

func (*NodeGroup) IncreaseSize

func (n *NodeGroup) IncreaseSize(delta int) error

IncreaseSize increases the size of the node group. To delete a node you need to explicitly name it and use DeleteNode. This function should wait until node group size is updated. Implementation required.

func (*NodeGroup) MaxSize

func (n *NodeGroup) MaxSize() int

MaxSize returns maximum size of the node group.

func (*NodeGroup) MinSize

func (n *NodeGroup) MinSize() int

MinSize returns minimum size of the node group.

func (*NodeGroup) Nodes

func (n *NodeGroup) Nodes() ([]cloudprovider.Instance, error)

Nodes returns a list of all nodes that belong to this node group. It is required that Instance objects returned by this method have Id field set. Other fields are optional.

func (*NodeGroup) TargetSize

func (n *NodeGroup) TargetSize() (int, error)

TargetSize returns the current target size of the node group. It is possible that the number of nodes in Kubernetes is different at the moment but should be equal to Size() once everything stabilizes (new nodes finish startup and registration or removed nodes are deleted completely). Implementation required.

func (*NodeGroup) TemplateNodeInfo

func (n *NodeGroup) TemplateNodeInfo() (*framework.NodeInfo, error)

TemplateNodeInfo returns a framework.NodeInfo structure of an empty (as if just started) node. This will be used in scale-up simulations to predict what would a new node look like if a node group was expanded. The returned NodeInfo is expected to have a fully populated Node object, with all of the labels, capacity and allocatable information as well as all pods that are started on the node by default, using manifest (most likely only kube-proxy). Implementation optional.