Expose more info: current context, is in kluster, is dev env

README.md

@@ -18,7 +18,7 @@ The main aspect of this is around saving and cleaning the code for in-cluster an
 Run `go get` to get the *k8s-discovery* module as follows.
 
 ```
-go get github.com/gkarthiks/k8s-discovery
+go get github.com/sysbind/k8s-discovery
 ```
 
 Declare a variable as `var k8s *discovery.K8s` and initialize it as `k8s, _ = discovery.NewK8s()`. Now the **k8s** will hold the interface that will provide the clientset for Kubernetes communication that is pulled either via `in-cluster` or via `kubeconfig` file.

discovery.go

@@ -9,6 +9,7 @@ import (
 	log "github.com/sirupsen/logrus"
 	coreClient "k8s.io/client-go/kubernetes"
 	restClient "k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
 	cmdClient "k8s.io/client-go/tools/clientcmd"
 	metricsClient "k8s.io/metrics/pkg/client/clientset/versioned"
 )
@@ -18,8 +19,31 @@ type K8s struct {
 	Clientset        coreClient.Interface
 	MetricsClientSet *metricsClient.Clientset
 	RestConfig       *restClient.Config
+	inKluster        bool
+	isDevEnv         bool
+	currentContext   string // only for out-of-kluster config
 }
 
+// dev/production env detection, copied from Tilt
+type Env string
+
+const (
+	EnvUnknown       Env = "unknown"
+	EnvGKE           Env = "gke"
+	EnvMinikube      Env = "minikube"
+	EnvDockerDesktop Env = "docker-for-desktop"
+	EnvMicroK8s      Env = "microk8s"
+	EnvCRC           Env = "crc"
+	EnvKrucible      Env = "krucible"
+	// Kind v0.6 substantially changed the protocol for detecting and pulling,
+	// so we represent them as two separate envs.
+	EnvKIND5          Env = "kind-0.5-"
+	EnvKIND6          Env = "kind-0.6+"
+	EnvK3D            Env = "k3d"
+	EnvRancherDesktop Env = "rancher-desktop"
+	EnvNone           Env = "none" // k8s not running (not neces. a problem, e.g. if using Tilt x Docker Compose)
+)
+
 var logEnabled bool
 
 // NewK8s will provide a new k8s client interface
@@ -28,16 +52,26 @@ var logEnabled bool
 // While running inside the cluster resolved via pod environment uses the in-cluster config
 func NewK8s() (*K8s, error) {
 	client := K8s{}
+
 	_, logEnabled = os.LookupEnv("CLIENTSET_LOG")
 
+	client.inKluster = true
+	client.isDevEnv = false
 	config, err := restClient.InClusterConfig()
 	if err != nil {
+		client.inKluster = false
 		kubeConfig :=
 			cmdClient.NewDefaultClientConfigLoadingRules().GetDefaultFilename()
 		config, err = cmdClient.BuildConfigFromFlags("", kubeConfig)
 		if err != nil {
 			return nil, err
 		}
+
+		err = client.addContextInfo(kubeConfig)
+		if err != nil {
+			return nil, err
+		}
+
 		if logEnabled {
 			log.Info("Program running from outside of the cluster")
 		}
@@ -80,3 +114,43 @@ func (o *K8s) GetNamespace() (string, error) {
 	}
 	return "", nil
 }
+
+func (o *K8s) IsInKluster() bool {
+	return o.inKluster
+}
+
+func (o *K8s) IsDevEnv() bool {
+	return o.isDevEnv
+}
+
+func (o *K8s) CurrentContext() string {
+	return o.currentContext
+}
+
+func (e Env) isDevCluster() bool {
+	return e == EnvMinikube ||
+		e == EnvDockerDesktop ||
+		e == EnvMicroK8s ||
+		e == EnvCRC ||
+		e == EnvKIND5 ||
+		e == EnvKIND6 ||
+		e == EnvK3D ||
+		e == EnvKrucible ||
+		e == EnvRancherDesktop
+}
+
+func (o *K8s) addContextInfo(kubeConfig string) (err error) {
+	// write down current context
+	rawconfig, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
+		&clientcmd.ClientConfigLoadingRules{ExplicitPath: kubeConfig},
+		&clientcmd.ConfigOverrides{
+			CurrentContext: "",
+		}).RawConfig()
+	if err != nil {
+		return
+	}
+	o.currentContext = rawconfig.CurrentContext
+	env := Env(o.currentContext)
+	o.isDevEnv = env.isDevCluster()
+	return
+}

go.mod

@@ -1,4 +1,4 @@
-module github.com/gkarthiks/k8s-discovery
+module github.com/sysbind/k8s-discovery
 
 go 1.19