proxy

Documentation

Overview

Among other files, this directory contains functionality for two stream proxies: streamtranslator.go and streamtunnel.go. Both of these proxies allow the inter-connection of WebSocket and SPDY streaming connections.

The stream translator proxy is used for the RemoteCommand subprotocol (e.g. kubectl exec, cp, and attach), and it connects the output streams of a WebSocket connection (e.g. STDIN, STDOUT, STDERR, TTY resize, and error streams) to the input streams of a SPDY connection.

The stream tunnel proxy tunnels SPDY frames through a WebSocket connection, and it is used for the PortForward subprotocol (e.g. kubectl port-forward). This proxy implements tunneling by transparently encoding and decoding SPDY framed data into and out of the payload of a WebSocket data frame. The primary structure for this tunneling is the TunnelingConnection. A lot of the other code in streamtunnel.go is for properly upgrading both the upstream SPDY connection and the downstream WebSocket connection before streaming begins.

Index

• func NewRequestForProxy(location *url.URL, req *http.Request) (*http.Request, context.CancelFunc)
• func NewTranslatingHandler(delegate http.Handler, translator http.Handler, ...) http.Handler
• func ResolveCluster(services listersv1.ServiceLister, namespace, id string, port int32) (*url.URL, error)
• func ResolveEndpoint(services listersv1.ServiceLister, endpoints listersv1.EndpointsLister, ...) (*url.URL, error)
• type Options
• type StreamTranslatorHandler
  • func NewStreamTranslatorHandler(location *url.URL, transport http.RoundTripper, maxBytesPerSec int64, ...) *StreamTranslatorHandler
  • func (h *StreamTranslatorHandler) ServeHTTP(w http.ResponseWriter, req *http.Request)
• type TunnelingHandler
  • func NewTunnelingHandler(upgradeHandler http.Handler) *TunnelingHandler
  • func (h *TunnelingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request)

Functions

func NewRequestForProxy

func NewRequestForProxy(location *url.URL, req *http.Request) (*http.Request, context.CancelFunc)

NewRequestForProxy returns a shallow copy of the original request with a context that may include a timeout for discovery requests

func NewTranslatingHandler

func NewTranslatingHandler(delegate http.Handler, translator http.Handler, shouldTranslate func(*http.Request) bool) http.Handler

func ResolveCluster

func ResolveCluster(services listersv1.ServiceLister, namespace, id string, port int32) (*url.URL, error)

func ResolveEndpoint

func ResolveEndpoint(services listersv1.ServiceLister, endpoints listersv1.EndpointsLister, namespace, id string, port int32) (*url.URL, error)

ResolveEndpoint returns a URL to which one can send traffic for the specified service.

Types

type Options

type Options struct {
	Stdin  bool
	Stdout bool
	Stderr bool
	Tty    bool
}

Options contains details about which streams are required for remote command execution.

type StreamTranslatorHandler

type StreamTranslatorHandler struct {
	// Location is the location of the upstream proxy. It is used as the location to Dial on the upstream server
	// for upgrade requests.
	Location *url.URL
	// Transport provides an optional round tripper to use to proxy. If nil, the default proxy transport is used
	Transport http.RoundTripper
	// MaxBytesPerSec throttles stream Reader/Writer if necessary
	MaxBytesPerSec int64
	// Options define the requested streams (e.g. stdin, stdout).
	Options Options
}

StreamTranslatorHandler is a handler which translates WebSocket stream data to SPDY to proxy to kubelet (and ContainerRuntime).

func NewStreamTranslatorHandler

func NewStreamTranslatorHandler(location *url.URL, transport http.RoundTripper, maxBytesPerSec int64, opts Options) *StreamTranslatorHandler

NewStreamTranslatorHandler creates a new proxy handler. Responder is required for returning errors to the caller.

func (*StreamTranslatorHandler) ServeHTTP

func (h *StreamTranslatorHandler) ServeHTTP(w http.ResponseWriter, req *http.Request)

type TunnelingHandler

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

TunnelingHandler is a handler which tunnels SPDY through WebSockets.

func NewTunnelingHandler

func NewTunnelingHandler(upgradeHandler http.Handler) *TunnelingHandler

NewTunnelingHandler is used to create the tunnel between an upstream SPDY connection and a downstream tunneling connection through the stored UpgradeAwareProxy.

func (*TunnelingHandler) ServeHTTP

func (h *TunnelingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request)

ServeHTTP uses the upgradeHandler to tunnel between a downstream tunneling connection and an upstream SPDY connection. The tunneling connection is a wrapped WebSockets connection which communicates SPDY framed data. In the case the upstream upgrade fails, we delegate communication to the passed in "w" ResponseWriter.