helm/cmd/helm/init.go

/*
Copyright 2016 The Kubernetes Authors All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package main

import (
	"errors"
	"fmt"
	"io"
	"os"

	"github.com/spf13/cobra"

	"k8s.io/helm/pkg/getter"
	"k8s.io/helm/pkg/helm/helmpath"
	"k8s.io/helm/pkg/repo"
)

const initDesc = `
This command sets up local configuration in $HELM_HOME (default ~/.helm/).
`

const stableRepository = "stable"

var stableRepositoryURL = "https://kubernetes-charts.storage.googleapis.com"

type initCmd struct {
	skipRefresh bool
	home        helmpath.Home
}

func newInitCmd(out io.Writer) *cobra.Command {
	i := &initCmd{}

	cmd := &cobra.Command{
		Use:   "init",
		Short: "initialize Helm client",
		Long:  initDesc,
		RunE: func(cmd *cobra.Command, args []string) error {
			if len(args) != 0 {
				return errors.New("This command does not accept arguments")
			}
			i.home = settings.Home
			return i.run(out)
		},
	}

	f := cmd.Flags()
	f.BoolVar(&i.skipRefresh, "skip-refresh", false, "do not refresh (download) the local repository cache")
	f.StringVar(&stableRepositoryURL, "stable-repo-url", stableRepositoryURL, "URL for stable repository")

	return cmd
}

// run initializes local config and installs Tiller to Kubernetes cluster.
func (i *initCmd) run(out io.Writer) error {
	if err := ensureDirectories(i.home, out); err != nil {
		return err
	}
	if err := ensureDefaultRepos(i.home, out, i.skipRefresh); err != nil {
		return err
	}
	if err := ensureRepoFileFormat(i.home.RepositoryFile(), out); err != nil {
		return err
	}
	fmt.Fprintf(out, "$HELM_HOME has been configured at %s.\n", settings.Home)
	fmt.Fprintln(out, "Happy Helming!")
	return nil
}

// ensureDirectories checks to see if $HELM_HOME exists.
//
// If $HELM_HOME does not exist, this function will create it.
func ensureDirectories(home helmpath.Home, out io.Writer) error {
	configDirectories := []string{
		home.String(),
		home.Repository(),
		home.Cache(),
		home.Plugins(),
		home.Starters(),
		home.Archive(),
	}
	for _, p := range configDirectories {
		if fi, err := os.Stat(p); err != nil {
			fmt.Fprintf(out, "Creating %s \n", p)
			if err := os.MkdirAll(p, 0755); err != nil {
				return fmt.Errorf("Could not create %s: %s", p, err)
			}
		} else if !fi.IsDir() {
			return fmt.Errorf("%s must be a directory", p)
		}
	}

	return nil
}

func ensureDefaultRepos(home helmpath.Home, out io.Writer, skipRefresh bool) error {
	repoFile := home.RepositoryFile()
	if fi, err := os.Stat(repoFile); err != nil {
		fmt.Fprintf(out, "Creating %s \n", repoFile)
		f := repo.NewRepoFile()
		sr, err := initStableRepo(home.CacheIndex(stableRepository), out, skipRefresh, home)
		if err != nil {
			return err
		}
		f.Add(sr)
		if err := f.WriteFile(repoFile, 0644); err != nil {
			return err
		}
	} else if fi.IsDir() {
		return fmt.Errorf("%s must be a file, not a directory", repoFile)
	}
	return nil
}

func initStableRepo(cacheFile string, out io.Writer, skipRefresh bool, home helmpath.Home) (*repo.Entry, error) {
	fmt.Fprintf(out, "Adding %s repo with URL: %s \n", stableRepository, stableRepositoryURL)
	c := repo.Entry{
		Name:  stableRepository,
		URL:   stableRepositoryURL,
		Cache: cacheFile,
	}
	r, err := repo.NewChartRepository(&c, getter.All(settings))
	if err != nil {
		return nil, err
	}

	if skipRefresh {
		return &c, nil
	}

	// In this case, the cacheFile is always absolute. So passing empty string
	// is safe.
	if err := r.DownloadIndexFile(""); err != nil {
		return nil, fmt.Errorf("Looks like %q is not a valid chart repository or cannot be reached: %s", stableRepositoryURL, err.Error())
	}

	return &c, nil
}

func ensureRepoFileFormat(file string, out io.Writer) error {
	r, err := repo.LoadRepositoriesFile(file)
	if err == repo.ErrRepoOutOfDate {
		fmt.Fprintln(out, "Updating repository file format...")
		if err := r.WriteFile(file, 0644); err != nil {
			return err
		}
	}
	return nil
}