cmd_export_kubeconfig.go

package main

import (
	"fmt"
	"os"

	"github.com/MusicDin/kubitect/pkg/app"
	"github.com/MusicDin/kubitect/pkg/utils/file"

	"github.com/spf13/cobra"
)

var (
	exportKcShort = "Export cluster kubeconfig file"
	exportKcLong  = LongDesc(`
		Command export kubeconfig outputs cluster's kubeconfig file to standard output.`)

	exportKcExample = Example(`
		To save a kubeconfig to the specific file, redirect command output to that file:
		> kubitect export kubeconfig --cluster lake > lake.yaml

		Use kubeconfig with kubectl to access cluster:
		> kubectl --kubeconfig lake.yaml get nodes`)
)

type ExportKcOptions struct {
	ClusterName string

	app.AppContextOptions
}

func NewExportKcCmd() *cobra.Command {
	var o ExportKcOptions

	cmd := &cobra.Command{
		SuggestFor: []string{"kubecfg", "kube", "kc"},
		Use:        "kubeconfig",
		GroupID:    "main",
		Short:      exportKcShort,
		Long:       exportKcLong,
		Example:    exportKcExample,
		RunE: func(cmd *cobra.Command, args []string) error {
			return o.Run()
		},
	}

	cmd.PersistentFlags().StringVar(&o.ClusterName, "cluster", "", "specify the cluster to be used")
	cmd.MarkPersistentFlagRequired("cluster")

	cmd.RegisterFlagCompletionFunc("cluster", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
		var names []string

		clusters, err := AllClusters(o.AppContext())

		if err != nil {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		for _, c := range clusters {
			if c.ContainsKubeconfig() {
				names = append(names, c.Name)
			}
		}

		return names, cobra.ShellCompDirectiveNoFileComp
	})

	return cmd
}

func (o *ExportKcOptions) Run() error {
	cs, err := AllClusters(o.AppContext())

	c := cs.FindByName(o.ClusterName)

	if c == nil {
		return fmt.Errorf("cluster '%s' does not exist", o.ClusterName)
	}

	count := cs.CountByName(o.ClusterName)

	if count > 1 {
		return fmt.Errorf("multiple clusters (%d) have been found with the name '%s'", count, o.ClusterName)
	}

	if !c.ContainsKubeconfig() {
		return fmt.Errorf("cluster '%s' does not have a Kubeconfig file", o.ClusterName)
	}

	kc, err := file.Read(c.KubeconfigPath())

	if err != nil {
		return err
	}

	fmt.Fprint(os.Stdout, kc)

	return nil
}