Method forward

tools/portforward/portforward.go:204–237

forward dials the remote host specific in req, upgrades the request, starts listeners for each port specified in ports, and forwards local connections to the remote host via streams.

()

// listeners for each port specified in ports, and forwards local connections
// to the remote host via streams.
func (pf *PortForwarder) forward() error {
	var err error

	listenSuccess := false
	for i := range pf.ports {
		port := &pf.ports[i]
		err = pf.listenOnPort(port)
		switch {
		case err == nil:
			listenSuccess = true
		default:
			if pf.errOut != nil {
				fmt.Fprintf(pf.errOut, "Unable to listen on port %d: %v\n", port.Local, err)
			}
		}
	}

	if !listenSuccess {
		return fmt.Errorf("Unable to listen on any of the requested ports: %v", pf.ports)
	}

	if pf.Ready != nil {
		close(pf.Ready)
	}

	// wait for interrupt or conn closure
	select {
	case <-pf.stopChan:
	case <-pf.streamConn.CloseChan():
		runtime.HandleError(errors.New("lost connection to pod"))
	}

	return nil
}

// listenOnPort delegates listener creation and waits for connections on requested bind addresses.
// An error is raised based on address groups (default and localhost) and their failure modes