Example #1
0
// This probably shouldn't be called ServeHTTP anymore
func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request, addrs []string) {

	pr := &ProxyRequest{
		ResponseWriter: rw,
		Request:        req,
		Backends:       addrs,
	}

	for _, f := range p.OnRequest {
		cont := f(pr)
		if !cont {
			return
		}
	}

	pr.StartTime = time.Now()
	res, err := p.doRequest(pr)

	pr.Response = res
	pr.ProxyError = err
	pr.FinishTime = time.Now()

	if err != nil {
		log.Errorf("ERROR: HTTP proxy error - %v", err)

		// We want to ensure that we have a non-nil response even on error for
		// the OnResponse callbacks. If the Callback chain completes, this will
		// be written to the client.
		res = &http.Response{
			Header:     make(map[string][]string),
			StatusCode: http.StatusBadGateway,
			Status:     http.StatusText(http.StatusBadGateway),
			// this ensures Body isn't nil
			Body: ioutil.NopCloser(bytes.NewReader(nil)),
		}
		pr.Response = res
	}

	for _, h := range hopHeaders {
		res.Header.Del(h)
	}

	copyHeader(rw.Header(), res.Header)

	for _, f := range p.OnResponse {
		cont := f(pr)
		if !cont {
			return
		}
	}

	// calls all completed with true, write the Response back to the client.
	defer res.Body.Close()
	rw.WriteHeader(res.StatusCode)
	_, err = p.copyResponse(rw, res.Body)
	if err != nil {
		log.Warnf("WARN: id=%s transfer error: %s", req.Header.Get("X-Request-Id"), err)
	}
}
Example #2
0
func (b *Backend) check() {
	if b.CheckAddr == "" {
		return
	}

	up := true
	if c, e := net.DialTimeout("tcp", b.CheckAddr, b.dialTimeout); e == nil {
		c.(*net.TCPConn).SetLinger(0)
		c.Close()
	} else {
		log.Warnf("WARN: Backend check for %s failed with error:", e)
		up = false
	}

	b.Lock()
	defer b.Unlock()
	if up {
		log.Debugf("DEBUG: Check OK for %s/%s", b.Name, b.CheckAddr)
		b.fallCount = 0
		b.riseCount++
		b.checkOK++
		if b.riseCount >= b.rise {
			if !b.up {
				log.Warnf("WARN: Marking backend %s Up", b.Name)
			}
			b.up = true
		}
	} else {
		log.Debugf("DEBUG: Check failed for %s/%s", b.Name, b.CheckAddr)
		b.riseCount = 0
		b.fallCount++
		b.checkFail++
		if b.fallCount >= b.fall {
			if b.up {
				log.Warnf("WARN: Marking backend %s Down", b.Name)
			}
			b.up = false
		}
	}
}
Example #3
0
// Return a *Service for this VirtualHost
func (v *VirtualHost) Service() *Service {
	v.Lock()
	defer v.Unlock()

	if len(v.services) == 0 {
		log.Warnf("WARN: No Services registered for VirtualHost %s", v.Name)
		return nil
	}

	// start cycling through the services in case one has no backends available
	for i := 1; i <= len(v.services); i++ {
		idx := (v.last + i) % len(v.services)
		if v.services[idx].Available() > 0 {
			v.last = idx
			return v.services[idx]
		}
	}

	// even if all backends are down, return a service so that the request can
	// be processed normally (we may have a custom 502 error page for this)
	return v.services[v.last]
}
Example #4
0
// Replace the service's configuration, or update its list of backends.
// Replacing a configuration will shutdown the existing service, and start a
// new one, which will cause the listening socket to be temporarily
// unavailable.
func (s *ServiceRegistry) UpdateService(newCfg client.ServiceConfig) error {
	s.Lock()
	defer s.Unlock()

	log.Debug("DEBUG: Updating Service:", newCfg.Name)
	service, ok := s.svcs[newCfg.Name]
	if !ok {
		log.Debug("DEBUG: Service not found:", newCfg.Name)
		return ErrNoService
	}

	currentCfg := service.Config()
	newCfg = currentCfg.Merge(newCfg)

	if err := service.UpdateConfig(newCfg); err != nil {
		return err
	}

	// Lots of looping here (including fetching the Config, but the cardinality
	// of Backends shouldn't be very large, and the default RoundRobin balancing
	// is much simpler with a slice.

	// we're going to update just the backends for this config
	// get a map of what's already running
	currentBackends := make(map[string]client.BackendConfig)
	for _, backendCfg := range currentCfg.Backends {
		currentBackends[backendCfg.Name] = backendCfg
	}

	// Keep existing backends when they have equivalent config.
	// Update changed backends, and add new ones.
	for _, newBackend := range newCfg.Backends {
		current, ok := currentBackends[newBackend.Name]
		if ok && current.Equal(newBackend) {
			log.Debugf("DEBUG: Backend %s/%s unchanged", service.Name, current.Name)
			// no change for this one
			delete(currentBackends, current.Name)
			continue
		}

		// we need to remove and re-add this backend
		log.Warnf("WARN: Updating Backend %s/%s", service.Name, newBackend.Name)
		service.remove(newBackend.Name)
		service.add(NewBackend(newBackend))

		delete(currentBackends, newBackend.Name)
	}

	// remove any left over backends
	for name := range currentBackends {
		log.Debugf("DEBUG: Removing Backend %s/%s", service.Name, name)
		service.remove(name)
	}

	if currentCfg.Equal(newCfg) {
		log.Debugf("DEBUG: Service Unchanged %s", service.Name)
		return nil
	}

	// replace error pages if there's any change
	if !reflect.DeepEqual(service.errPagesCfg, newCfg.ErrorPages) {
		log.Debugf("DEBUG: Updating ErrorPages")
		service.errPagesCfg = newCfg.ErrorPages
		service.errorPages.Update(newCfg.ErrorPages)
	}

	s.updateVHosts(service, filterEmpty(newCfg.VirtualHosts))

	return nil
}