bandit

Documentation

Index

• Constants
• type BanditDialer
  • func New(opts Options) (*BanditDialer, error)
  • func (o *BanditDialer) Close()
  • func (o *BanditDialer) DialContext(ctx context.Context, network, addr string) (net.Conn, error)
• type Dialer
• type Options

Constants

const (
	// NetworkConnect is a pseudo network name to instruct the dialer to establish
	// a CONNECT tunnel to the proxy.
	NetworkConnect = "connect"
	// NetworkPersistent is a pseudo network name to instruct the dialer to
	// signal the proxy to establish a persistent HTTP connection over which
	// one or more HTTP requests can be sent directly.
	NetworkPersistent = "persistent"
)

Types

type BanditDialer

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

BanditDialer is responsible for continually choosing the optimized dialer.

func New

func New(opts Options) (*BanditDialer, error)

New creates a new bandit given the available dialers and options with callbacks to be called when a dialer is selected, an error occurs, etc.

func (*BanditDialer) Close

func (o *BanditDialer) Close()

func (*BanditDialer) DialContext

func (o *BanditDialer) DialContext(ctx context.Context, network, addr string) (net.Conn, error)

type Dialer

type Dialer interface {

	// DialProxy dials the proxy but does not yet dial the origin.
	DialProxy(ctx context.Context) (net.Conn, error)

	// SupportsAddr indicates whether this Dialer supports the given addr. If it does not, the
	// balancer will not attempt to dial that addr with this Dialer.
	SupportsAddr(network, addr string) bool

	// DialContext dials out to the given origin. failedUpstream indicates whether
	// this was an upstream error (as opposed to errors connecting to the proxy).
	DialContext(ctx context.Context, network, addr string) (conn net.Conn, failedUpstream bool, err error)

	// Name returns the name for this Dialer
	Name() string

	// Label returns a label for this Dialer (includes Name plus more).
	Label() string

	// JustifiedLabel is like Label() but with elements justified for line-by
	// -line display.
	JustifiedLabel() string

	// Location returns the country code, country name and city name of the
	// dialer, in this order.
	Location() (string, string, string)

	// Protocol returns a string representation of the protocol used by this
	// Dialer.
	Protocol() string

	// Addr returns the address for this Dialer
	Addr() string

	// Trusted indicates whether or not this dialer is trusted
	Trusted() bool

	// NumPreconnecting returns the number of pending preconnect requests.
	NumPreconnecting() int

	// NumPreconnected returns the number of preconnected connections.
	NumPreconnected() int

	// MarkFailure marks a dial failure on this dialer.
	MarkFailure()

	// EstRTT provides a round trip delay time estimate, similar to how RTT is
	// estimated in TCP (https://tools.ietf.org/html/rfc6298)
	EstRTT() time.Duration

	// EstBandwidth provides the estimated bandwidth in Mbps
	EstBandwidth() float64

	// EstSuccessRate returns the estimated success rate dialing this dialer.
	EstSuccessRate() float64

	// Attempts returns the total number of dial attempts
	Attempts() int64

	// Successes returns the total number of dial successes
	Successes() int64

	// ConsecSuccesses returns the number of consecutive dial successes
	ConsecSuccesses() int64

	// Failures returns the total number of dial failures
	Failures() int64

	// ConsecFailures returns the number of consecutive dial failures
	ConsecFailures() int64

	// Succeeding indicates whether or not this dialer is currently good to use
	Succeeding() bool

	// DataSent returns total bytes of application data sent to connections
	// created via this dialer.
	DataSent() uint64
	// DataRecv returns total bytes of application data received from
	// connections created via this dialer.
	DataRecv() uint64

	// Stop stops background processing for this Dialer.
	Stop()

	WriteStats(w io.Writer)
}

Dialer provides the ability to dial a proxy and obtain information needed to effectively load balance between dialers.

type Options

type Options struct {
	// The available dialers to use when creating a new bandit
	Dialers []Dialer

	// OnError is the onError callback that is called when bandit encounters a dial error
	OnError func(error, bool)

	// OnSuccess is the callback that is called by bandit after a successful dial.
	OnSuccess func(Dialer)

	// StatsTracker is a stats.Tracker bandit should be configured to use (a callback that is called
	// when a dialer is selected)
	StatsTracker stats.Tracker
}

Options are the options used to create a new bandit