From 1ff59e3c1f9d9d3a3a7da9528f2cb4e05db53a39 Mon Sep 17 00:00:00 2001
From: Catherine Fang <yinghongfang@google.com>
Date: Tue, 26 Sep 2023 17:41:23 -0400
Subject: [PATCH] move to util.go

---
 pkg/app/server.go | 39 ---------------------------------------
 pkg/app/util.go   | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 39 deletions(-)
 create mode 100644 pkg/app/util.go

diff --git a/pkg/app/server.go b/pkg/app/server.go
index 3588648b07..279c032fed 100644
--- a/pkg/app/server.go
+++ b/pkg/app/server.go
@@ -26,13 +26,10 @@ import (
 	"net/http/pprof"
 	"os"
 	"path/filepath"
-	"runtime"
 	"strconv"
 	"strings"
 	"time"
 
-	"k8s.io/client-go/rest"
-
 	"github.com/oklog/run"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/collectors"
@@ -41,7 +38,6 @@ import (
 	"github.com/prometheus/common/version"
 	"github.com/prometheus/exporter-toolkit/web"
 	"gopkg.in/yaml.v3"
-	clientset "k8s.io/client-go/kubernetes"
 	_ "k8s.io/client-go/plugin/pkg/client/auth" // Initialize common client auth plugins.
 	"k8s.io/client-go/tools/clientcmd"
 	"k8s.io/klog/v2"
@@ -457,38 +453,3 @@ func resolveCustomResourceConfig(opts *options.Options) (customresourcestate.Con
 	}
 	return nil, nil
 }
-
-func createKubeClient(apiserver string, kubeconfig string) (clientset.Interface, error) {
-	var config *rest.Config
-
-	var err error
-
-	if config == nil {
-		config, err = clientcmd.BuildConfigFromFlags(apiserver, kubeconfig)
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	config.UserAgent = fmt.Sprintf("%s/%s (%s/%s) kubernetes/%s", "kube-state-metrics", version.Version, runtime.GOOS, runtime.GOARCH, version.Revision)
-	config.AcceptContentTypes = "application/vnd.kubernetes.protobuf,application/json"
-	config.ContentType = "application/vnd.kubernetes.protobuf"
-
-	kubeClient, err := clientset.NewForConfig(config)
-	if err != nil {
-		return nil, err
-	}
-
-	// Informers don't seem to do a good job logging error messages when it
-	// can't reach the server, making debugging hard. This makes it easier to
-	// figure out if apiserver is configured incorrectly.
-	klog.InfoS("Tested communication with server")
-	v, err := kubeClient.Discovery().ServerVersion()
-	if err != nil {
-		return nil, fmt.Errorf("error while trying to communicate with apiserver: %w", err)
-	}
-	klog.InfoS("Run with Kubernetes cluster version", "major", v.Major, "minor", v.Minor, "gitVersion", v.GitVersion, "gitTreeState", v.GitTreeState, "gitCommit", v.GitCommit, "platform", v.Platform)
-	klog.InfoS("Communication with server successful")
-
-	return kubeClient, nil
-}
diff --git a/pkg/app/util.go b/pkg/app/util.go
new file mode 100644
index 0000000000..082ea1d4ce
--- /dev/null
+++ b/pkg/app/util.go
@@ -0,0 +1,47 @@
+package app
+
+import (
+	"fmt"
+	"runtime"
+
+	"github.com/prometheus/common/version"
+	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+	"k8s.io/klog/v2"
+)
+
+func createKubeClient(apiserver string, kubeconfig string) (clientset.Interface, error) {
+	var config *rest.Config
+
+	var err error
+
+	if config == nil {
+		config, err = clientcmd.BuildConfigFromFlags(apiserver, kubeconfig)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	config.UserAgent = fmt.Sprintf("%s/%s (%s/%s) kubernetes/%s", "kube-state-metrics", version.Version, runtime.GOOS, runtime.GOARCH, version.Revision)
+	config.AcceptContentTypes = "application/vnd.kubernetes.protobuf,application/json"
+	config.ContentType = "application/vnd.kubernetes.protobuf"
+
+	kubeClient, err := clientset.NewForConfig(config)
+	if err != nil {
+		return nil, err
+	}
+
+	// Informers don't seem to do a good job logging error messages when it
+	// can't reach the server, making debugging hard. This makes it easier to
+	// figure out if apiserver is configured incorrectly.
+	klog.InfoS("Tested communication with server")
+	v, err := kubeClient.Discovery().ServerVersion()
+	if err != nil {
+		return nil, fmt.Errorf("error while trying to communicate with apiserver: %w", err)
+	}
+	klog.InfoS("Run with Kubernetes cluster version", "major", v.Major, "minor", v.Minor, "gitVersion", v.GitVersion, "gitTreeState", v.GitTreeState, "gitCommit", v.GitCommit, "platform", v.Platform)
+	klog.InfoS("Communication with server successful")
+
+	return kubeClient, nil
+}