package connection import ( "fmt" "net/url" "strings" tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs" "github.com/rs/zerolog" ) const ( LogFieldLocation = "location" observerChannelBufferSize = 16 ) type Observer struct { log *zerolog.Logger metrics *tunnelMetrics tunnelEventChan chan Event uiEnabled bool addSinkChan chan EventSink } type EventSink interface { OnTunnelEvent(event Event) } func NewObserver(log *zerolog.Logger, uiEnabled bool) *Observer { o := &Observer{ log: log, metrics: newTunnelMetrics(), uiEnabled: uiEnabled, tunnelEventChan: make(chan Event, observerChannelBufferSize), addSinkChan: make(chan EventSink, observerChannelBufferSize), } go o.dispatchEvents() return o } func (o *Observer) RegisterSink(sink EventSink) { o.addSinkChan <- sink } func (o *Observer) logServerInfo(connIndex uint8, location, msg string) { o.sendEvent(Event{Index: connIndex, EventType: Connected, Location: location}) o.log.Info(). Uint8(LogFieldConnIndex, connIndex). Str(LogFieldLocation, location). Msg(msg) o.metrics.registerServerLocation(uint8ToString(connIndex), location) } func (o *Observer) logTrialHostname(registration *tunnelpogs.TunnelRegistration) error { // Print out the user's trial zone URL in a nice box (if they requested and got one and UI flag is not set) if !o.uiEnabled { if registrationURL, err := url.Parse(registration.Url); err == nil { for _, line := range asciiBox(trialZoneMsg(registrationURL.String()), 2) { o.log.Info().Msg(line) } } else { o.log.Error().Msg("Failed to connect tunnel, please try again.") return fmt.Errorf("empty URL in response from Cloudflare edge") } } return nil } // Print out the given lines in a nice ASCII box. func asciiBox(lines []string, padding int) (box []string) { maxLen := maxLen(lines) spacer := strings.Repeat(" ", padding) border := "+" + strings.Repeat("-", maxLen+(padding*2)) + "+" box = append(box, border) for _, line := range lines { box = append(box, "|"+spacer+line+strings.Repeat(" ", maxLen-len(line))+spacer+"|") } box = append(box, border) return } func maxLen(lines []string) int { max := 0 for _, line := range lines { if len(line) > max { max = len(line) } } return max } func trialZoneMsg(url string) []string { return []string{ "Your free tunnel has started! Visit it:", " " + url, } } func (o *Observer) sendRegisteringEvent() { o.sendEvent(Event{EventType: RegisteringTunnel}) } func (o *Observer) sendConnectedEvent(connIndex uint8, location string) { o.sendEvent(Event{Index: connIndex, EventType: Connected, Location: location}) } func (o *Observer) sendURL(url string) { o.sendEvent(Event{EventType: SetURL, URL: url}) } func (o *Observer) SendReconnect(connIndex uint8) { o.sendEvent(Event{Index: connIndex, EventType: Reconnecting}) } func (o *Observer) SendDisconnect(connIndex uint8) { o.sendEvent(Event{Index: connIndex, EventType: Disconnected}) } func (o *Observer) sendEvent(e Event) { select { case o.tunnelEventChan <- e: break default: o.log.Warn().Msg("observer channel buffer is full") } } func (o *Observer) dispatchEvents() { var sinks []EventSink for { select { case sink := <-o.addSinkChan: sinks = append(sinks, sink) case evt := <-o.tunnelEventChan: for _, sink := range sinks { sink.OnTunnelEvent(evt) } } } } type EventSinkFunc func(event Event) func (f EventSinkFunc) OnTunnelEvent(event Event) { f(event) }