simpledns

Documentation

Overview

Package simpledns discovers config API servers by performing simple DNS queries.

It is not a DNS-SD implementation. It requires all API servers to listen on the same port.

Index

• Constants
• type Discoverer
  • func (d *Discoverer) Run(ctx context.Context) error
• type Resolver

Constants

const (
	// DefaultInterval is the default interval at which DNS queries are performed.
	DefaultInterval = 10 * time.Second

	// DefaultServerPort is the default server TCP port.
	DefaultServerPort = "https"
)

const (
	// QueryHostKey is the target meta-data key for the hostname used in the DNS
	// query that discovered the target.
	QueryHostKey key = "simpledns.query-host"
)

Types

type Discoverer

type Discoverer struct {
	QueryHost  string
	ServerPort string
	Observer   discovery.TargetObserver
	Interval   time.Duration
	Resolver   Resolver
	// contains filtered or unexported fields
}

Discoverer periodically performs a DNS query to discover API servers and notifies a target observer.

func (*Discoverer) Run

func (d *Discoverer) Run(ctx context.Context) error

Run performs discovery until ctx is canceled or an error occurs.

type Resolver

type Resolver interface {
	LookupHost(ctx context.Context, host string) ([]string, error)
}

Resolver is an interface for the subset of net.Resolver used by the discoverer.