package server import ( "context" "encoding/json" "net/http" "os" "os/signal" "sync" "time" "github.com/containous/traefik/v2/pkg/config/dynamic" "github.com/containous/traefik/v2/pkg/config/runtime" "github.com/containous/traefik/v2/pkg/config/static" "github.com/containous/traefik/v2/pkg/log" "github.com/containous/traefik/v2/pkg/metrics" "github.com/containous/traefik/v2/pkg/middlewares/accesslog" "github.com/containous/traefik/v2/pkg/middlewares/requestdecorator" "github.com/containous/traefik/v2/pkg/provider" "github.com/containous/traefik/v2/pkg/safe" "github.com/containous/traefik/v2/pkg/server/middleware" "github.com/containous/traefik/v2/pkg/tls" "github.com/containous/traefik/v2/pkg/tracing" "github.com/containous/traefik/v2/pkg/tracing/jaeger" "github.com/containous/traefik/v2/pkg/types" ) // Server is the reverse-proxy/load-balancer engine type Server struct { entryPointsTCP TCPEntryPoints configurationChan chan dynamic.Message configurationValidatedChan chan dynamic.Message signals chan os.Signal stopChan chan bool currentConfigurations safe.Safe providerConfigUpdateMap map[string]chan dynamic.Message accessLoggerMiddleware *accesslog.Handler tracer *tracing.Tracing routinesPool *safe.Pool defaultRoundTripper http.RoundTripper metricsRegistry metrics.Registry provider provider.Provider configurationListeners []func(dynamic.Configuration) requestDecorator *requestdecorator.RequestDecorator providersThrottleDuration time.Duration tlsManager *tls.Manager } // RouteAppenderFactory the route appender factory interface type RouteAppenderFactory interface { NewAppender(ctx context.Context, middlewaresBuilder *middleware.Builder, runtimeConfiguration *runtime.Configuration) types.RouteAppender } func setupTracing(conf *static.Tracing) tracing.Backend { var backend tracing.Backend if conf.Jaeger != nil { backend = conf.Jaeger } if conf.Zipkin != nil { if backend != nil { log.WithoutContext().Error("Multiple tracing backend are not supported: cannot create Zipkin backend.") } else { backend = conf.Zipkin } } if conf.DataDog != nil { if backend != nil { log.WithoutContext().Error("Multiple tracing backend are not supported: cannot create DataDog backend.") } else { backend = conf.DataDog } } if conf.Instana != nil { if backend != nil { log.WithoutContext().Error("Multiple tracing backend are not supported: cannot create Instana backend.") } else { backend = conf.Instana } } if conf.Haystack != nil { if backend != nil { log.WithoutContext().Error("Multiple tracing backend are not supported: cannot create Haystack backend.") } else { backend = conf.Haystack } } if backend == nil { log.WithoutContext().Debug("Could not initialize tracing, use Jaeger by default") backend := &jaeger.Config{} backend.SetDefaults() } return backend } // NewServer returns an initialized Server. func NewServer(staticConfiguration static.Configuration, provider provider.Provider, entryPoints TCPEntryPoints, tlsManager *tls.Manager) *Server { server := &Server{} server.provider = provider server.entryPointsTCP = entryPoints server.configurationChan = make(chan dynamic.Message, 100) server.configurationValidatedChan = make(chan dynamic.Message, 100) server.signals = make(chan os.Signal, 1) server.stopChan = make(chan bool, 1) server.configureSignals() currentConfigurations := make(dynamic.Configurations) server.currentConfigurations.Set(currentConfigurations) server.providerConfigUpdateMap = make(map[string]chan dynamic.Message) server.tlsManager = tlsManager if staticConfiguration.Providers != nil { server.providersThrottleDuration = time.Duration(staticConfiguration.Providers.ProvidersThrottleDuration) } transport, err := createHTTPTransport(staticConfiguration.ServersTransport) if err != nil { log.WithoutContext().Errorf("Could not configure HTTP Transport, fallbacking on default transport: %v", err) server.defaultRoundTripper = http.DefaultTransport } else { server.defaultRoundTripper = transport } server.routinesPool = safe.NewPool(context.Background()) if staticConfiguration.Tracing != nil { tracingBackend := setupTracing(staticConfiguration.Tracing) if tracingBackend != nil { server.tracer, err = tracing.NewTracing(staticConfiguration.Tracing.ServiceName, staticConfiguration.Tracing.SpanNameLimit, tracingBackend) if err != nil { log.WithoutContext().Warnf("Unable to create tracer: %v", err) } } } server.requestDecorator = requestdecorator.New(staticConfiguration.HostResolver) server.metricsRegistry = registerMetricClients(staticConfiguration.Metrics) if staticConfiguration.AccessLog != nil { var err error server.accessLoggerMiddleware, err = accesslog.NewHandler(staticConfiguration.AccessLog) if err != nil { log.WithoutContext().Warnf("Unable to create access logger : %v", err) } } return server } // Start starts the server and Stop/Close it when context is Done func (s *Server) Start(ctx context.Context) { go func() { defer s.Close() <-ctx.Done() logger := log.FromContext(ctx) logger.Info("I have to go...") logger.Info("Stopping server gracefully") s.Stop() }() s.startTCPServers() s.routinesPool.Go(func(stop chan bool) { s.listenProviders(stop) }) s.routinesPool.Go(func(stop chan bool) { s.listenConfigurations(stop) }) s.startProvider() s.routinesPool.Go(func(stop chan bool) { s.listenSignals(stop) }) } // Wait blocks until server is shutted down. func (s *Server) Wait() { <-s.stopChan } // Stop stops the server func (s *Server) Stop() { defer log.WithoutContext().Info("Server stopped") var wg sync.WaitGroup for epn, ep := range s.entryPointsTCP { wg.Add(1) go func(entryPointName string, entryPoint *TCPEntryPoint) { ctx := log.With(context.Background(), log.Str(log.EntryPointName, entryPointName)) defer wg.Done() entryPoint.Shutdown(ctx) log.FromContext(ctx).Debugf("Entry point %s closed", entryPointName) }(epn, ep) } wg.Wait() s.stopChan <- true } // Close destroys the server func (s *Server) Close() { ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second) go func(ctx context.Context) { <-ctx.Done() if ctx.Err() == context.Canceled { return } else if ctx.Err() == context.DeadlineExceeded { panic("Timeout while stopping traefik, killing instance ✝") } }(ctx) stopMetricsClients() s.routinesPool.Cleanup() close(s.configurationChan) close(s.configurationValidatedChan) signal.Stop(s.signals) close(s.signals) close(s.stopChan) if s.accessLoggerMiddleware != nil { if err := s.accessLoggerMiddleware.Close(); err != nil { log.WithoutContext().Errorf("Could not close the access log file: %s", err) } } if s.tracer != nil { s.tracer.Close() } cancel() } func (s *Server) startTCPServers() { // Use an empty configuration in order to initialize the default handlers with internal routes routers := s.loadConfigurationTCP(dynamic.Configurations{}) for entryPointName, router := range routers { s.entryPointsTCP[entryPointName].switchRouter(router) } for entryPointName, serverEntryPoint := range s.entryPointsTCP { ctx := log.With(context.Background(), log.Str(log.EntryPointName, entryPointName)) go serverEntryPoint.startTCP(ctx) } } func (s *Server) listenProviders(stop chan bool) { for { select { case <-stop: return case configMsg, ok := <-s.configurationChan: if !ok { return } if configMsg.Configuration != nil { s.preLoadConfiguration(configMsg) } else { log.Debugf("Received nil configuration from provider %q, skipping.", configMsg.ProviderName) } } } } // AddListener adds a new listener function used when new configuration is provided func (s *Server) AddListener(listener func(dynamic.Configuration)) { if s.configurationListeners == nil { s.configurationListeners = make([]func(dynamic.Configuration), 0) } s.configurationListeners = append(s.configurationListeners, listener) } func (s *Server) startProvider() { jsonConf, err := json.Marshal(s.provider) if err != nil { log.WithoutContext().Debugf("Unable to marshal provider configuration %T: %v", s.provider, err) } log.WithoutContext().Infof("Starting provider %T %s", s.provider, jsonConf) currentProvider := s.provider safe.Go(func() { err := currentProvider.Provide(s.configurationChan, s.routinesPool) if err != nil { log.WithoutContext().Errorf("Error starting provider %T: %s", s.provider, err) } }) } func registerMetricClients(metricsConfig *types.Metrics) metrics.Registry { if metricsConfig == nil { return metrics.NewVoidRegistry() } var registries []metrics.Registry if metricsConfig.Prometheus != nil { ctx := log.With(context.Background(), log.Str(log.MetricsProviderName, "prometheus")) prometheusRegister := metrics.RegisterPrometheus(ctx, metricsConfig.Prometheus) if prometheusRegister != nil { registries = append(registries, prometheusRegister) log.FromContext(ctx).Debug("Configured Prometheus metrics") } } if metricsConfig.DataDog != nil { ctx := log.With(context.Background(), log.Str(log.MetricsProviderName, "datadog")) registries = append(registries, metrics.RegisterDatadog(ctx, metricsConfig.DataDog)) log.FromContext(ctx).Debugf("Configured DataDog metrics: pushing to %s once every %s", metricsConfig.DataDog.Address, metricsConfig.DataDog.PushInterval) } if metricsConfig.StatsD != nil { ctx := log.With(context.Background(), log.Str(log.MetricsProviderName, "statsd")) registries = append(registries, metrics.RegisterStatsd(ctx, metricsConfig.StatsD)) log.FromContext(ctx).Debugf("Configured StatsD metrics: pushing to %s once every %s", metricsConfig.StatsD.Address, metricsConfig.StatsD.PushInterval) } if metricsConfig.InfluxDB != nil { ctx := log.With(context.Background(), log.Str(log.MetricsProviderName, "influxdb")) registries = append(registries, metrics.RegisterInfluxDB(ctx, metricsConfig.InfluxDB)) log.FromContext(ctx).Debugf("Configured InfluxDB metrics: pushing to %s once every %s", metricsConfig.InfluxDB.Address, metricsConfig.InfluxDB.PushInterval) } return metrics.NewMultiRegistry(registries) } func stopMetricsClients() { metrics.StopDatadog() metrics.StopStatsd() metrics.StopInfluxDB() }