1 files changed, 64 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/modules/k8s_state/client.go b/src/go/collectors/go.d.plugin/modules/k8s_state/client.go
new file mode 100644
index 000000000..315e823fe
--- /dev/null
+++ b/src/go/collectors/go.d.plugin/modules/k8s_state/client.go
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package k8s_state
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+
+	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
+
+	"github.com/mattn/go-isatty"
+)
+
+const (
+	envKubeServiceHost = "KUBERNETES_SERVICE_HOST"
+	envKubeServicePort = "KUBERNETES_SERVICE_PORT"
+)
+
+func newKubeClient() (kubernetes.Interface, error) {
+	if os.Getenv(envKubeServiceHost) != "" && os.Getenv(envKubeServicePort) != "" {
+		return newKubeClientInCluster()
+	}
+	if isatty.IsTerminal(os.Stdout.Fd()) {
+		return newKubeClientOutOfCluster()
+	}
+	return nil, errors.New("can not create Kubernetes client: not inside a cluster")
+}
+
+func newKubeClientInCluster() (*kubernetes.Clientset, error) {
+	config, err := rest.InClusterConfig()
+	if err != nil {
+		return nil, err
+	}
+	config.UserAgent = "Netdata/kube-state"
+	return kubernetes.NewForConfig(config)
+}
+
+func newKubeClientOutOfCluster() (*kubernetes.Clientset, error) {
+	home := homeDir()
+	if home == "" {
+		return nil, errors.New("couldn't find home directory")
+	}
+
+	configPath := filepath.Join(home, ".kube", "config")
+	config, err := clientcmd.BuildConfigFromFlags("", configPath)
+	if err != nil {
+		return nil, err
+	}
+
+	config.UserAgent = "Netdata/kube-state"
+	return kubernetes.NewForConfig(config)
+}
+
+func homeDir() string {
+	if h := os.Getenv("HOME"); h != "" {
+		return h
+	}
+	return os.Getenv("USERPROFILE") // windows
+}