softplayer-backend/internal/helpers/helm/helm.go

package helm

import (
	"fmt"
	"os"

	"github.com/sirupsen/logrus"
	"gopkg.in/yaml.v2"
	"helm.sh/helm/v3/pkg/action"
	"helm.sh/helm/v3/pkg/chart/loader"
	"helm.sh/helm/v3/pkg/chartutil"
	"helm.sh/helm/v3/pkg/cli"
	"helm.sh/helm/v3/pkg/engine"
	"helm.sh/helm/v3/pkg/getter"
	"helm.sh/helm/v3/pkg/registry"
	"helm.sh/helm/v3/pkg/repo"
)

type Helm struct{}

func NewHelm() Helmhelper {
	return &Helm{}
}

func getDownloadDirPath(workdirPath string) string {
	return fmt.Sprintf("%s/.charts", workdirPath)
}

func getChartDirPath(downloadDirPath string, release *ReleaseData) string {
	return fmt.Sprintf("%s/%s-%s-%s", downloadDirPath, release.RepositoryName, release.Chart, release.Version)

}

func (h *Helm) PullChart(workdirPath string, release *ReleaseData) (path string, err error) {
	downloadDirPath := getDownloadDirPath(workdirPath)
	if err := os.MkdirAll(downloadDirPath, 0777); err != nil {
		return "", err
	}

	config := new(action.Configuration)
	cl := cli.New()
	chartDir := getChartDirPath(downloadDirPath, release)
	_, err = os.Stat(chartDir)

	if err != nil && !os.IsNotExist(err) {
		return "", nil
	} else if os.IsNotExist(err) {
		if err := os.Mkdir(chartDir, 0777); err != nil {
			return "", err
		}
		registry, err := registry.NewClient()
		if err != nil {
			return "", err
		}

		var path string
		// Download the chart to the workdir
		if release.RepositoryKind != "oci" {
			r, err := repo.NewChartRepository(&repo.Entry{
				Name: release.RepositoryName,
				URL:  release.RepositoryURL,
			}, getter.All(cl))
			if err != nil {
				return "", err
			}
			path = r.Config.Name

		} else {
			path = release.RepositoryURL
		}

		client := action.NewPullWithOpts(action.WithConfig(config))

		client.Untar = true
		client.UntarDir = workdirPath
		client.SetRegistryClient(registry)
		client.DestDir = workdirPath
		client.Settings = cl

		chartRemote := fmt.Sprintf("%s/%s", path, release.Chart)
		logrus.Infof("trying to pull: %s", chartRemote)
		if _, err = client.Run(chartRemote); err != nil {
			return "", err
		}
	}
	return release.Chart, nil
}

func (h *Helm) FindLatestVersion(workdirPath string, release *ReleaseData) (version string, err error) {
	downloadDirPath := getDownloadDirPath(workdirPath)
	if err := os.MkdirAll(downloadDirPath, 0777); err != nil {
		return "", err
	}

	config := new(action.Configuration)
	cl := cli.New()
	chartDir := getChartDirPath(downloadDirPath, release)
	chartPath, err := h.PullChart(workdirPath, release)
	if err != nil {
		return "", err
	}

	showAction := action.NewShowWithConfig(action.ShowChart, config)

	res, err := showAction.LocateChart(fmt.Sprintf("%s/%s", chartDir, chartPath), cl)
	if err != nil {
		return "", err
	}
	res, err = showAction.Run(res)
	if err != nil {
		return "", nil
	}

	chartData, err := chartFromString(res)
	if err != nil {
		return "", err
	}
	logrus.Infof("the latest version of %s is %s", release.Chart, chartData.Version)
	versionedChartDir := getChartDirPath(downloadDirPath, release)
	os.Rename(chartDir, versionedChartDir)
	return chartData.Version, err
}

func (h *Helm) RenderChart(workdirPath string, release *ReleaseData) error {
	downloadDirPath := getDownloadDirPath(workdirPath)
	chartDirPath := getChartDirPath(downloadDirPath, release)
	chartPath, err := getChartPathFromDir(chartDirPath)
	if err != nil {
		return err
	}
	logrus.Info(fmt.Sprintf("%s/%s", chartDirPath, chartPath))
	chartObj, err := loader.Load(fmt.Sprintf("%s/%s", chartDirPath, chartPath))
	if err != nil {
		return err
	}
	values := chartutil.Values{}
	values["Values"] = chartObj.Values
	values["Release"] = map[string]string{
		"Name":      release.Name,
		"Namespace": release.Namespace,
	}
	values["Capabilities"] = map[string]map[string]string{
		"KubeVersion": {
			"Version":    "v1.27.9",
			"GitVersion": "v1.27.9",
		},
	}
	files, err := engine.Engine{Strict: false}.Render(chartObj, values)
	if err != nil {
		return err
	}
	logrus.Info(files)
	for file, data := range files {
		logrus.Infof("%s - %s", file, data)
	}
	logrus.Info("I'm here")
	return nil
}

func getChartPathFromDir(downloadDir string) (file string, err error) {
	files, err := os.ReadDir(downloadDir)
	if err != nil {
		return "", err
	} else if len(files) == 0 {
		return "", fmt.Errorf("expected to have one file, got zero in a dir %s", downloadDir)
	} else if len(files) > 1 {
		return "", fmt.Errorf("expected to have only one file in a dir %s", downloadDir)
	}
	return files[0].Name(), nil
}

func chartFromString(info string) (*ReleaseData, error) {
	releaseData := new(ReleaseData)
	if err := yaml.Unmarshal([]byte(info), &releaseData); err != nil {
		return nil, err
	}
	return releaseData, nil
}