コード例 #1
0
ファイル: frontend.go プロジェクト: vnadgir-ef/vulcand
func (f *frontend) rebuild() error {
	settings := f.frontend.HTTPSettings()

	// set up forwarder
	fwd, err := forward.New(
		forward.Logger(f.log),
		forward.RoundTripper(f.backend.transport),
		forward.Rewriter(
			&forward.HeaderRewriter{
				Hostname:           settings.Hostname,
				TrustForwardHeader: settings.TrustForwardHeader,
			}),
		forward.PassHostHeader(settings.PassHostHeader))

	// rtwatcher will be observing and aggregating metrics
	watcher, err := NewWatcher(fwd)
	if err != nil {
		return err
	}

	// Create a load balancer
	rr, err := roundrobin.New(watcher)
	if err != nil {
		return err
	}

	// Rebalancer will readjust load balancer weights based on error ratios
	rb, err := roundrobin.NewRebalancer(rr, roundrobin.RebalancerLogger(f.log))
	if err != nil {
		return err
	}

	// create middlewares sorted by priority and chain them
	middlewares := f.sortedMiddlewares()
	handlers := make([]http.Handler, len(middlewares))
	for i, m := range middlewares {
		var prev http.Handler
		if i == 0 {
			prev = rb
		} else {
			prev = handlers[i-1]
		}
		h, err := m.Middleware.NewHandler(prev)
		if err != nil {
			return err
		}
		handlers[i] = h
	}

	var next http.Handler
	if len(handlers) != 0 {
		next = handlers[len(handlers)-1]
	} else {
		next = rb
	}

	// stream will retry and replay requests, fix encodings
	if settings.FailoverPredicate == "" {
		settings.FailoverPredicate = `IsNetworkError() && RequestMethod() == "GET" && Attempts() < 2`
	}
	str, err := stream.New(next,
		stream.Logger(f.log),
		stream.Retry(settings.FailoverPredicate),
		stream.MaxRequestBodyBytes(settings.Limits.MaxBodyBytes),
		stream.MemRequestBodyBytes(settings.Limits.MaxMemBodyBytes))
	if err != nil {
		return err
	}

	if err := syncServers(f.mux, rb, f.backend, watcher); err != nil {
		return err
	}

	// Add the frontend to the router
	if err := f.mux.router.Handle(f.frontend.Route, str); err != nil {
		return err
	}

	f.lb = rb
	f.handler = str
	f.watcher = watcher
	return nil
}
コード例 #2
0
ファイル: server.go プロジェクト: vdemeester/traefik
// LoadConfig returns a new gorilla.mux Route from the specified global configuration and the dynamic
// provider configurations.
func (server *Server) loadConfig(configurations configs, globalConfiguration GlobalConfiguration) (map[string]*serverEntryPoint, error) {
	serverEntryPoints := server.buildEntryPoints(globalConfiguration)
	redirectHandlers := make(map[string]http.Handler)

	backends := map[string]http.Handler{}
	backend2FrontendMap := map[string]string{}
	for _, configuration := range configurations {
		frontendNames := sortedFrontendNamesForConfig(configuration)
	frontend:
		for _, frontendName := range frontendNames {
			frontend := configuration.Frontends[frontendName]

			log.Debugf("Creating frontend %s", frontendName)

			fwd, err := forward.New(forward.Logger(oxyLogger), forward.PassHostHeader(frontend.PassHostHeader))
			if err != nil {
				log.Errorf("Error creating forwarder for frontend %s: %v", frontendName, err)
				log.Errorf("Skipping frontend %s...", frontendName)
				continue frontend
			}
			saveBackend := middlewares.NewSaveBackend(fwd)
			if len(frontend.EntryPoints) == 0 {
				log.Errorf("No entrypoint defined for frontend %s, defaultEntryPoints:%s", frontendName, globalConfiguration.DefaultEntryPoints)
				log.Errorf("Skipping frontend %s...", frontendName)
				continue frontend
			}
			for _, entryPointName := range frontend.EntryPoints {
				log.Debugf("Wiring frontend %s to entryPoint %s", frontendName, entryPointName)
				if _, ok := serverEntryPoints[entryPointName]; !ok {
					log.Errorf("Undefined entrypoint '%s' for frontend %s", entryPointName, frontendName)
					log.Errorf("Skipping frontend %s...", frontendName)
					continue frontend
				}
				newServerRoute := &serverRoute{route: serverEntryPoints[entryPointName].httpRouter.GetHandler().NewRoute().Name(frontendName)}
				for routeName, route := range frontend.Routes {
					err := getRoute(newServerRoute, &route)
					if err != nil {
						log.Errorf("Error creating route for frontend %s: %v", frontendName, err)
						log.Errorf("Skipping frontend %s...", frontendName)
						continue frontend
					}
					log.Debugf("Creating route %s %s", routeName, route.Rule)
				}
				entryPoint := globalConfiguration.EntryPoints[entryPointName]
				if entryPoint.Redirect != nil {
					if redirectHandlers[entryPointName] != nil {
						newServerRoute.route.Handler(redirectHandlers[entryPointName])
					} else if handler, err := server.loadEntryPointConfig(entryPointName, entryPoint); err != nil {
						log.Errorf("Error loading entrypoint configuration for frontend %s: %v", frontendName, err)
						log.Errorf("Skipping frontend %s...", frontendName)
						continue frontend
					} else {
						newServerRoute.route.Handler(handler)
						redirectHandlers[entryPointName] = handler
					}
				} else {
					if backends[frontend.Backend] == nil {
						log.Debugf("Creating backend %s", frontend.Backend)
						var lb http.Handler
						rr, _ := roundrobin.New(saveBackend)
						if configuration.Backends[frontend.Backend] == nil {
							log.Errorf("Undefined backend '%s' for frontend %s", frontend.Backend, frontendName)
							log.Errorf("Skipping frontend %s...", frontendName)
							continue frontend
						}

						lbMethod, err := types.NewLoadBalancerMethod(configuration.Backends[frontend.Backend].LoadBalancer)
						if err != nil {
							log.Errorf("Error loading load balancer method '%+v' for frontend %s: %v", configuration.Backends[frontend.Backend].LoadBalancer, frontendName, err)
							log.Errorf("Skipping frontend %s...", frontendName)
							continue frontend
						}

						stickysession := configuration.Backends[frontend.Backend].LoadBalancer.Sticky
						cookiename := "_TRAEFIK_BACKEND"
						var sticky *roundrobin.StickySession

						if stickysession {
							sticky = roundrobin.NewStickySession(cookiename)
						}

						switch lbMethod {
						case types.Drr:
							log.Debugf("Creating load-balancer drr")
							rebalancer, _ := roundrobin.NewRebalancer(rr, roundrobin.RebalancerLogger(oxyLogger))
							if stickysession {
								log.Debugf("Sticky session with cookie %v", cookiename)
								rebalancer, _ = roundrobin.NewRebalancer(rr, roundrobin.RebalancerLogger(oxyLogger), roundrobin.RebalancerStickySession(sticky))
							}
							lb = rebalancer
							for serverName, server := range configuration.Backends[frontend.Backend].Servers {
								url, err := url.Parse(server.URL)
								if err != nil {
									log.Errorf("Error parsing server URL %s: %v", server.URL, err)
									log.Errorf("Skipping frontend %s...", frontendName)
									continue frontend
								}
								backend2FrontendMap[url.String()] = frontendName
								log.Debugf("Creating server %s at %s with weight %d", serverName, url.String(), server.Weight)
								if err := rebalancer.UpsertServer(url, roundrobin.Weight(server.Weight)); err != nil {
									log.Errorf("Error adding server %s to load balancer: %v", server.URL, err)
									log.Errorf("Skipping frontend %s...", frontendName)
									continue frontend
								}
							}
						case types.Wrr:
							log.Debugf("Creating load-balancer wrr")
							if stickysession {
								log.Debugf("Sticky session with cookie %v", cookiename)
								rr, _ = roundrobin.New(saveBackend, roundrobin.EnableStickySession(sticky))
							}
							lb = rr
							for serverName, server := range configuration.Backends[frontend.Backend].Servers {
								url, err := url.Parse(server.URL)
								if err != nil {
									log.Errorf("Error parsing server URL %s: %v", server.URL, err)
									log.Errorf("Skipping frontend %s...", frontendName)
									continue frontend
								}
								backend2FrontendMap[url.String()] = frontendName
								log.Debugf("Creating server %s at %s with weight %d", serverName, url.String(), server.Weight)
								if err := rr.UpsertServer(url, roundrobin.Weight(server.Weight)); err != nil {
									log.Errorf("Error adding server %s to load balancer: %v", server.URL, err)
									log.Errorf("Skipping frontend %s...", frontendName)
									continue frontend
								}
							}
						}
						maxConns := configuration.Backends[frontend.Backend].MaxConn
						if maxConns != nil && maxConns.Amount != 0 {
							extractFunc, err := utils.NewExtractor(maxConns.ExtractorFunc)
							if err != nil {
								log.Errorf("Error creating connlimit: %v", err)
								log.Errorf("Skipping frontend %s...", frontendName)
								continue frontend
							}
							log.Debugf("Creating loadd-balancer connlimit")
							lb, err = connlimit.New(lb, extractFunc, maxConns.Amount, connlimit.Logger(oxyLogger))
							if err != nil {
								log.Errorf("Error creating connlimit: %v", err)
								log.Errorf("Skipping frontend %s...", frontendName)
								continue frontend
							}
						}
						// retry ?
						if globalConfiguration.Retry != nil {
							retries := len(configuration.Backends[frontend.Backend].Servers)
							if globalConfiguration.Retry.Attempts > 0 {
								retries = globalConfiguration.Retry.Attempts
							}
							lb = middlewares.NewRetry(retries, lb)
							log.Debugf("Creating retries max attempts %d", retries)
						}

						var negroni = negroni.New()
						if configuration.Backends[frontend.Backend].CircuitBreaker != nil {
							log.Debugf("Creating circuit breaker %s", configuration.Backends[frontend.Backend].CircuitBreaker.Expression)
							cbreaker, err := middlewares.NewCircuitBreaker(lb, configuration.Backends[frontend.Backend].CircuitBreaker.Expression, cbreaker.Logger(oxyLogger))
							if err != nil {
								log.Errorf("Error creating circuit breaker: %v", err)
								log.Errorf("Skipping frontend %s...", frontendName)
								continue frontend
							}
							negroni.Use(cbreaker)
						} else {
							negroni.UseHandler(lb)
						}
						backends[frontend.Backend] = negroni
					} else {
						log.Debugf("Reusing backend %s", frontend.Backend)
					}
					if frontend.Priority > 0 {
						newServerRoute.route.Priority(frontend.Priority)
					}
					server.wireFrontendBackend(newServerRoute, backends[frontend.Backend])
				}
				err := newServerRoute.route.GetError()
				if err != nil {
					log.Errorf("Error building route: %s", err)
				}
			}
		}
	}
	middlewares.SetBackend2FrontendMap(&backend2FrontendMap)
	//sort routes
	for _, serverEntryPoint := range serverEntryPoints {
		serverEntryPoint.httpRouter.GetHandler().SortRoutes()
	}
	return serverEntryPoints, nil
}