heartbeat

Documentation

Index

• Variables
• func NewHeartbeatStatusTracker(client MemorystoreClient[v2.HeartbeatMessage]) *heartbeatStatusTracker
• type Locator
  • func NewServerLocator(tracker StatusTracker) *Locator
  • func (l *Locator) Nearest(service, typ string, lat, lon float64) ([]v2.Target, []url.URL, error)
• type MemorystoreClient
• type StatusTracker

Variables

var (
	// ErrNoAvailableServers is returned when there are no available servers
	ErrNoAvailableServers = errors.New("no available M-Lab servers")
)

Functions

func NewHeartbeatStatusTracker

func NewHeartbeatStatusTracker(client MemorystoreClient[v2.HeartbeatMessage]) *heartbeatStatusTracker

NewHeartbeatStatusTracker returns a new StatusTracker implementation that uses a Memorystore client to cache (and later import) instance data from the Heartbeat Service. StopImport() must be called to release resources.

Types

type Locator

type Locator struct {
	StatusTracker
}

Locator manages requests to "locate" mlab-ns servers.

func NewServerLocator

func NewServerLocator(tracker StatusTracker) *Locator

NewServerLocator creates a new Locator instance.

func (*Locator) Nearest

func (l *Locator) Nearest(service, typ string, lat, lon float64) ([]v2.Target, []url.URL, error)

Nearest discovers the nearest machines for the target service, using an exponentially distributed function based on distance.

type MemorystoreClient

type MemorystoreClient[V any] interface {
	Put(key string, field string, value redis.Scanner, expire bool) error
	GetAll() (map[string]V, error)
}

MemorystoreClient is a client for reading and writing data in Memorystore. The interface takes in a type argument which specifies the types of values that are stored and can be retrived.

type StatusTracker

type StatusTracker interface {
	RegisterInstance(rm v2.Registration) error
	UpdateHealth(hostname string, hm v2.Health) error
	UpdatePrometheus(hostnames, machines map[string]bool) error
	Instances() map[string]v2.HeartbeatMessage
	StopImport()
}

StatusTracker defines the interface for tracking the status of experiment instances.