package provider import ( log "github.com/Sirupsen/logrus" "github.com/cenkalti/backoff" "github.com/containous/traefik/provider/k8s" "github.com/containous/traefik/safe" "github.com/containous/traefik/types" "io" "io/ioutil" "os" "strings" "text/template" "time" ) const ( serviceAccountToken = "/var/run/secrets/kubernetes.io/serviceaccount/token" serviceAccountCACert = "/var/run/secrets/kubernetes.io/serviceaccount/ca.crt" ) // Kubernetes holds configurations of the Kubernetes provider. type Kubernetes struct { BaseProvider `mapstructure:",squash"` Endpoint string } func (provider *Kubernetes) createClient() (k8s.Client, error) { var token string tokenBytes, err := ioutil.ReadFile(serviceAccountToken) if err == nil { token = string(tokenBytes) log.Debugf("Kubernetes token: %s", token) } else { log.Errorf("Kubernetes load token error: %s", err) } caCert, err := ioutil.ReadFile(serviceAccountCACert) if err == nil { log.Debugf("Kubernetes CA cert: %s", serviceAccountCACert) } else { log.Errorf("Kubernetes load token error: %s", err) } kubernetesHost := os.Getenv("KUBERNETES_SERVICE_HOST") kubernetesPort := os.Getenv("KUBERNETES_SERVICE_PORT_HTTPS") if len(kubernetesPort) > 0 && len(kubernetesHost) > 0 { provider.Endpoint = "https://" + kubernetesHost + ":" + kubernetesPort } log.Debugf("Kubernetes endpoint: %s", provider.Endpoint) return k8s.NewClient(provider.Endpoint, caCert, token) } // Provide allows the provider to provide configurations to traefik // using the given configuration channel. func (provider *Kubernetes) Provide(configurationChan chan<- types.ConfigMessage, pool *safe.Pool) error { k8sClient, err := provider.createClient() if err != nil { return err } backOff := backoff.NewExponentialBackOff() pool.Go(func(stop chan bool) { stopWatch := make(chan bool) defer close(stopWatch) operation := func() error { select { case <-stop: return nil default: } for { eventsChan, errEventsChan, err := k8sClient.WatchAll(stopWatch) if err != nil { log.Errorf("Error watching kubernetes events: %v", err) return err } Watch: for { select { case <-stop: stopWatch <- true return nil case err := <-errEventsChan: if strings.Contains(err.Error(), io.EOF.Error()) { // edge case, kubernetes long-polling disconnection break Watch } return err case event := <-eventsChan: log.Debugf("Received event from kubenetes %+v", event) templateObjects, err := provider.loadIngresses(k8sClient) if err != nil { return err } configurationChan <- types.ConfigMessage{ ProviderName: "kubernetes", Configuration: provider.loadConfig(*templateObjects), } } } } } notify := func(err error, time time.Duration) { log.Errorf("Kubernetes connection error %+v, retrying in %s", err, time) } err := backoff.RetryNotify(operation, backOff, notify) if err != nil { log.Fatalf("Cannot connect to Kubernetes server %+v", err) } }) templateObjects, err := provider.loadIngresses(k8sClient) if err != nil { return err } configurationChan <- types.ConfigMessage{ ProviderName: "kubernetes", Configuration: provider.loadConfig(*templateObjects), } return nil } func (provider *Kubernetes) loadIngresses(k8sClient k8s.Client) (*types.Configuration, error) { ingresses, err := k8sClient.GetIngresses(func(ingress k8s.Ingress) bool { return true }) if err != nil { log.Errorf("Error retrieving ingresses: %+v", err) return nil, err } templateObjects := types.Configuration{ map[string]*types.Backend{}, map[string]*types.Frontend{}, } for _, i := range ingresses { for _, r := range i.Spec.Rules { for _, pa := range r.HTTP.Paths { if _, exists := templateObjects.Backends[r.Host+pa.Path]; !exists { templateObjects.Backends[r.Host+pa.Path] = &types.Backend{ Servers: make(map[string]types.Server), } } if _, exists := templateObjects.Frontends[r.Host+pa.Path]; !exists { templateObjects.Frontends[r.Host+pa.Path] = &types.Frontend{ Backend: r.Host + pa.Path, Routes: make(map[string]types.Route), } } if _, exists := templateObjects.Frontends[r.Host+pa.Path].Routes[r.Host]; !exists { templateObjects.Frontends[r.Host+pa.Path].Routes[r.Host] = types.Route{ Rule: "Host:" + r.Host, } } if len(pa.Path) > 0 { templateObjects.Frontends[r.Host+pa.Path].Routes[pa.Path] = types.Route{ Rule: "PathPrefixStrip:" + pa.Path, } } services, err := k8sClient.GetServices(func(service k8s.Service) bool { return service.Name == pa.Backend.ServiceName }) if err != nil { log.Errorf("Error retrieving services: %v", err) continue } if len(services) == 0 { // no backends found, delete frontend... delete(templateObjects.Frontends, r.Host+pa.Path) log.Errorf("Error retrieving services %s", pa.Backend.ServiceName) } for _, service := range services { var protocol string for _, port := range service.Spec.Ports { if port.Port == pa.Backend.ServicePort.IntValue() { protocol = port.Name templateObjects.Backends[r.Host+pa.Path].Servers[string(service.UID)] = types.Server{ URL: protocol + "://" + service.Spec.ClusterIP + ":" + pa.Backend.ServicePort.String(), Weight: 1, } break } } } } } } return &templateObjects, nil } func (provider *Kubernetes) loadConfig(templateObjects types.Configuration) *types.Configuration { var FuncMap = template.FuncMap{} configuration, err := provider.getConfiguration("templates/kubernetes.tmpl", FuncMap, templateObjects) if err != nil { log.Error(err) } return configuration }