Merge branch 'master' into k8_upgrade

kubernetes/kubernetes.go

@@ -1,6 +1,9 @@
 package kubernetes
 
 import (
+	"fmt"
+	"os"
+
 	"github.com/golang/glog"
 
 	cfg "github.com/asobti/kube-monkey/config"
@@ -9,8 +12,49 @@ import (
 	"k8s.io/client-go/rest"
 )
 
+// Check if running in a cluster with service accounts
+// Use case: firewall based/only cluster 
+func RunningInCluster() (bool)  {
+        if _, err := os.Stat("/var/run/secrets/kubernetes.io/serviceaccount/token"); err == nil {
+                return true;
+        } else {
+                return false;
+        }
+}
+
+func GetConfig() (*rest.Config, error) {
+        var kubeConfig rest.Config
+
+        // Set the Kubernetes configuration based on the environment
+        if RunningInCluster() {
+                config, err := rest.InClusterConfig()
+
+                if err != nil {
+                        return nil, fmt.Errorf("Failed to create in-cluster config: %v.", err)
+                }
+
+                kubeConfig = *config
+        } else {
+                loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
+                configOverrides := &clientcmd.ConfigOverrides{}
+                config := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, configOverrides)
+                tmpKubeConfig, err := config.ClientConfig()
+                if err != nil {
+                        return nil, fmt.Errorf("Failed to load local kube config: %v", err)
+                }
+                kubeConfig = *tmpKubeConfig;
+        }
+
+	if apiserverHost, override := cfg.ClusterAPIServerHost(); override {
+		glog.V(3).Infof("API server host overriden to: %s\n", apiserverHost)
+		kubeConfig.Host = apiserverHost
+	}
+
+        return &kubeConfig, nil
+}
+
 func NewInClusterClient() (*kube.Clientset, error) {
-	config, err := rest.InClusterConfig()
+	config, err := GetConfig()
 	if err != nil {
 		glog.Errorf("failed to obtain config from InClusterConfig: %v", err)
 		return nil, err