| /* |
| Copyright 2017 The Kubernetes Authors. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| package main |
| |
| import ( |
| "flag" |
| "fmt" |
| "os" |
| "strconv" |
| "strings" |
| "time" |
| |
| metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" |
| restclient "k8s.io/client-go/rest" |
| "k8s.io/client-go/tools/clientcmd" |
| clientapi "k8s.io/client-go/tools/clientcmd/api" |
| "k8s.io/klog" |
| api "k8s.io/kubernetes/pkg/apis/core" |
| clientset "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset" |
| ) |
| |
| func buildConfigFromEnvs(masterURL, kubeconfigPath string) (*restclient.Config, error) { |
| if kubeconfigPath == "" && masterURL == "" { |
| kubeconfig, err := restclient.InClusterConfig() |
| if err != nil { |
| return nil, err |
| } |
| |
| return kubeconfig, nil |
| } |
| |
| return clientcmd.NewNonInteractiveDeferredLoadingClientConfig( |
| &clientcmd.ClientConfigLoadingRules{ExplicitPath: kubeconfigPath}, |
| &clientcmd.ConfigOverrides{ClusterInfo: clientapi.Cluster{Server: masterURL}}).ClientConfig() |
| } |
| |
| func flattenSubsets(subsets []api.EndpointSubset) []string { |
| ips := []string{} |
| for _, ss := range subsets { |
| for _, addr := range ss.Addresses { |
| ips = append(ips, fmt.Sprintf(`"%s"`, addr.IP)) |
| } |
| } |
| return ips |
| } |
| |
| func main() { |
| flag.Parse() |
| |
| klog.Info("Kubernetes Elasticsearch logging discovery") |
| |
| cc, err := buildConfigFromEnvs(os.Getenv("APISERVER_HOST"), os.Getenv("KUBE_CONFIG_FILE")) |
| if err != nil { |
| klog.Fatalf("Failed to make client: %v", err) |
| } |
| client, err := clientset.NewForConfig(cc) |
| |
| if err != nil { |
| klog.Fatalf("Failed to make client: %v", err) |
| } |
| namespace := metav1.NamespaceSystem |
| envNamespace := os.Getenv("NAMESPACE") |
| if envNamespace != "" { |
| if _, err := client.Core().Namespaces().Get(envNamespace, metav1.GetOptions{}); err != nil { |
| klog.Fatalf("%s namespace doesn't exist: %v", envNamespace, err) |
| } |
| namespace = envNamespace |
| } |
| |
| var elasticsearch *api.Service |
| serviceName := os.Getenv("ELASTICSEARCH_SERVICE_NAME") |
| if serviceName == "" { |
| serviceName = "elasticsearch-logging" |
| } |
| |
| // Look for endpoints associated with the Elasticsearch logging service. |
| // First wait for the service to become available. |
| for t := time.Now(); time.Since(t) < 5*time.Minute; time.Sleep(10 * time.Second) { |
| elasticsearch, err = client.Core().Services(namespace).Get(serviceName, metav1.GetOptions{}) |
| if err == nil { |
| break |
| } |
| } |
| // If we did not find an elasticsearch logging service then log a warning |
| // and return without adding any unicast hosts. |
| if elasticsearch == nil { |
| klog.Warningf("Failed to find the elasticsearch-logging service: %v", err) |
| return |
| } |
| |
| var endpoints *api.Endpoints |
| addrs := []string{} |
| // Wait for some endpoints. |
| count, _ := strconv.Atoi(os.Getenv("MINIMUM_MASTER_NODES")) |
| for t := time.Now(); time.Since(t) < 5*time.Minute; time.Sleep(10 * time.Second) { |
| endpoints, err = client.Core().Endpoints(namespace).Get(serviceName, metav1.GetOptions{}) |
| if err != nil { |
| continue |
| } |
| addrs = flattenSubsets(endpoints.Subsets) |
| klog.Infof("Found %s", addrs) |
| if len(addrs) > 0 && len(addrs) >= count { |
| break |
| } |
| } |
| // If there was an error finding endpoints then log a warning and quit. |
| if err != nil { |
| klog.Warningf("Error finding endpoints: %v", err) |
| return |
| } |
| |
| klog.Infof("Endpoints = %s", addrs) |
| fmt.Printf("discovery.zen.ping.unicast.hosts: [%s]\n", strings.Join(addrs, ", ")) |
| } |