How to get namespace from current-context set in .kube/config
I found a solution using NewDefaultClientConfigLoadingRules
and then loading the rules. This works if your config is loadable with the default client config loading rules.
Example:
package main
import (
"github.com/davecgh/go-spew/spew"
"k8s.io/client-go/tools/clientcmd"
)
func main() {
clientCfg, err := clientcmd.NewDefaultClientConfigLoadingRules().Load()
spew.Dump(clientCfg, err)
}
Gives you a https://godoc.org/k8s.io/client-go/tools/clientcmd/api#Config which contains the current context including its namespace.
Contexts: (map[string]*api.Context) (len=1) {
(string) (len=17) "xxx.xxxxx.xxx": (*api.Context)(0xc0001b2b40)({
LocationOfOrigin: (string) (len=30) "/path/to/.kube/config",
Cluster: (string) (len=17) "xxx.xxxxx.xxx",
AuthInfo: (string) (len=29) "[email protected]",
Namespace: (string) (len=7) "default",
Extensions: (map[string]runtime.Object) {
}
})
},
CurrentContext: (string) (len=17) "xxx.xxxxx.xxx",
For your information, ClientConfigLoadingRules
is a structure with different properties to tell the client where to load the config from. The default one will use the path in your KUBECONFIG
environment variable in the Precedence
field.
(*clientcmd.ClientConfigLoadingRules)(0xc0000a31d0)({
ExplicitPath: (string) "",
Precedence: ([]string) (len=1 cap=1) {
(string) (len=30) "/path/to/.kube/config"
},
MigrationRules: (map[string]string) (len=1) {
(string) (len=30) "/path/to/.kube/config": (string) (len=35) "/path/to/.kube/.kubeconfig"
},
DoNotResolvePaths: (bool) false,
DefaultClientConfig: (clientcmd.ClientConfig) <nil>
})
This code, based on answer https://stackoverflow.com/a/55315895/2784039, returns the namespace set in the current context of the kubeconfig
file. In addition, it sets namespace
to default
if namespace
is not defined in the kubeconfig
current context:
package main
import (
"fmt"
"k8s.io/client-go/tools/clientcmd"
)
func main() {
clientCfg, _ := clientcmd.NewDefaultClientConfigLoadingRules().Load()
namespace := clientCfg.Contexts[clientCfg.CurrentContext].Namespace
if namespace == "" {
namespace = "default"
}
fmt.Printf(namespace)
}
This code works fine on user side, it it is run outside the cluster. Check comments below to retrieve namespace
for a pod inside the cluster.
import "k8s.io/client-go/tools/clientcmd"
loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
configOverrides := &clientcmd.ConfigOverrides{}
kubeConfig := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules,
configOverrides)
namespace, _, err = kubeConfig.Namespace()