Cache kubeconfig used for kubectl commands

cmd/common.go

@@ -34,11 +34,13 @@ import (
 	managementClient "github.com/rancher/types/client/management/v3"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli"
+	"k8s.io/client-go/tools/clientcmd/api"
 )
 
 const (
 	letters             = "abcdefghijklmnopqrstuvwxyz0123456789"
 	cfgFile             = "cli2.json"
+	kubeConfigKeyFormat = "%s-%s"
 )
 
 var (
@@ -143,6 +145,31 @@ func listRoleTemplateBindings(ctx *cli.Context, b []RoleTemplateBinding) error {
 	return writer.Err()
 }
 
+func getKubeConfigForUser(ctx *cli.Context, user string) (*api.Config, error) {
+	cf, err := loadConfig(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	focusedServer := cf.FocusedServer()
+	kubeConfig, _ := focusedServer.KubeConfigs[fmt.Sprintf(kubeConfigKeyFormat, user, focusedServer.FocusedCluster())]
+	return kubeConfig, nil
+}
+
+func setKubeConfigForUser(ctx *cli.Context, user string, kubeConfig *api.Config) error {
+	cf, err := loadConfig(ctx)
+	if err != nil {
+		return err
+	}
+
+	if cf.FocusedServer().KubeConfigs == nil {
+		cf.FocusedServer().KubeConfigs = make(map[string]*api.Config)
+	}
+	focusedServer := cf.FocusedServer()
+	focusedServer.KubeConfigs[fmt.Sprintf(kubeConfigKeyFormat, user, focusedServer.FocusedCluster())] = kubeConfig
+	return cf.Write()
+}
+
 func usersToNameMapping(u []managementClient.User) map[string]string {
 	userMapping := make(map[string]string)
 	for _, user := range u {

cmd/kubectl.go

@@ -5,8 +5,13 @@ import (
 	"io/ioutil"
 	"os"
 	"os/exec"
+	"strings"
 
+	"github.com/rancher/norman/clientbase"
+	client "github.com/rancher/types/client/management/v3"
 	"github.com/urfave/cli"
+	"k8s.io/client-go/tools/clientcmd"
+	"k8s.io/client-go/tools/clientcmd/api"
 )
 
 func KubectlCommand() cli.Command {
@@ -37,6 +42,41 @@ func runKubectl(ctx *cli.Context) error {
 		return err
 	}
 
+	config, err := loadConfig(ctx)
+	if err != nil {
+		return err
+	}
+
+	currentRancherServer := config.FocusedServer()
+	if currentRancherServer == nil {
+		return fmt.Errorf("no focused server")
+	}
+
+	currentToken := currentRancherServer.AccessKey
+	t, err := c.ManagementClient.Token.ByID(currentToken)
+	if err != nil {
+		return err
+	}
+
+	currentUser := t.UserID
+	kubeConfig, err := getKubeConfigForUser(ctx, currentUser)
+	if err != nil {
+		return err
+	}
+
+	var isTokenValid bool
+	if kubeConfig != nil {
+		tokenID, err := extractKubeconfigTokenID(*kubeConfig)
+		if err != nil {
+			return err
+		}
+		isTokenValid, err = validateToken(tokenID, c.ManagementClient.Token)
+		if err != nil {
+			return err
+		}
+	}
+
+	if kubeConfig == nil || !isTokenValid {
 		cluster, err := getClusterByID(c, c.UserConfig.FocusedCluster())
 		if err != nil {
 			return err
@@ -47,19 +87,27 @@ func runKubectl(ctx *cli.Context) error {
 			return err
 		}
 
+		kubeConfigBytes := []byte(config.Config)
+		kubeConfig, err = clientcmd.Load(kubeConfigBytes)
+		if err != nil {
+			return err
+		}
+
+		if err := setKubeConfigForUser(ctx, currentUser, kubeConfig); err != nil {
+			return err
+		}
+	}
+
 	tmpfile, err := ioutil.TempFile("", "rancher-")
 	if err != nil {
 		return err
 	}
 	defer os.Remove(tmpfile.Name())
 
-	_, err = tmpfile.Write([]byte(config.Config))
-	if err != nil {
+	if err := clientcmd.WriteToFile(*kubeConfig, tmpfile.Name()); err != nil {
 		return err
 	}
-
-	err = tmpfile.Close()
-	if err != nil {
+	if err := tmpfile.Close(); err != nil {
 		return err
 	}
 
@@ -74,3 +122,29 @@ func runKubectl(ctx *cli.Context) error {
 	}
 	return nil
 }
+
+func extractKubeconfigTokenID(kubeconfig api.Config) (string, error) {
+	if len(kubeconfig.AuthInfos) != 1 {
+		return "", fmt.Errorf("invalid kubeconfig, expected to contain exactly 1 user")
+	}
+	var parts []string
+	for _, val := range kubeconfig.AuthInfos {
+		parts = strings.Split(val.Token, ":")
+		if len(parts) != 2 {
+			return "", fmt.Errorf("failed to parse kubeconfig token")
+		}
+	}
+
+	return parts[0], nil
+}
+
+func validateToken(tokenID string, tokenClient client.TokenOperations) (bool, error) {
+	token, err := tokenClient.ByID(tokenID)
+	if err != nil {
+		if !clientbase.IsNotFound(err) {
+			return false, err
+		}
+		return false, nil
+	}
+	return !token.Expired, nil
+}

config/config.go

@@ -8,6 +8,7 @@ import (
 	"strings"
 
 	"github.com/sirupsen/logrus"
+	"k8s.io/client-go/tools/clientcmd/api"
 )
 
 // Config holds the main config for the user
@@ -28,6 +29,7 @@ type ServerConfig struct {
 	Project         string                     `json:"project"`
 	CACerts         string                     `json:"cacert"`
 	KubeCredentials map[string]*ExecCredential `json:"kubeCredentials"`
+	KubeConfigs     map[string]*api.Config     `json:"kubeConfigs"`
 }
 
 func (c Config) Write() error {

go.mod

@@ -24,4 +24,5 @@ require (
 	golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15
 	gopkg.in/yaml.v2 v2.2.8
+	k8s.io/client-go v12.0.0+incompatible
 )