arttor/helmify

package helm

import (
    "fmt"
    "os"
    "path/filepath"
    "strings"

    "github.com/arttor/helmify/pkg/cluster"
    "github.com/arttor/helmify/pkg/helmify"

    "github.com/sirupsen/logrus"

    "sigs.k8s.io/yaml"
)

// NewOutput creates interface to dump processed input to filesystem in Helm chart format.
func NewOutput() helmify.Output {
    return &output{}
}

type output struct{}

// Create a helm chart in the current directory:
// chartName/
//
//    ├── .helmignore       # Contains patterns to ignore when packaging Helm charts.
//    ├── Chart.yaml        # Information about your chart
//    ├── values.yaml       # The default values for your templates
//    └── templates/        # The template files
//        └── _helpers.tp   # Helm default template partials
//
// Overwrites existing values.yaml and templates in templates dir on every run.
func (o output) Create(chartDir, chartName string, crd bool, certManagerAsSubchart bool, certManagerVersion string, templates []helmify.Template, filenames []string) error {
    err := initChartDir(chartDir, chartName, crd, certManagerAsSubchart, certManagerVersion)
    if err != nil {
        return err
    }
    // group templates into files
    files := map[string][]helmify.Template{}
    values := helmify.Values{}
    values[cluster.DomainKey] = cluster.DefaultDomain
    for i, template := range templates {
        file := files[filenames[i]]
        file = append(file, template)
        files[filenames[i]] = file
        err = values.Merge(template.Values())
        if err != nil {
            return err
        }
    }
    cDir := filepath.Join(chartDir, chartName)
    for filename, tpls := range files {
        err = overwriteTemplateFile(filename, cDir, crd, tpls)
        if err != nil {
            return err
        }
    }
    err = overwriteValuesFile(cDir, values, certManagerAsSubchart)
    if err != nil {
        return err
    }
    return nil
}

func overwriteTemplateFile(filename, chartDir string, crd bool, templates []helmify.Template) error {
    // pull in crd-dir setting and siphon crds into folder
    var subdir string
    if strings.Contains(filename, "crd") && crd {
        subdir = "crds"
        // create "crds" if not exists
        if _, err := os.Stat(filepath.Join(chartDir, "crds")); os.IsNotExist(err) {
            err = os.MkdirAll(filepath.Join(chartDir, "crds"), 0750)
            if err != nil {
                return fmt.Errorf("%w: unable create crds dir", err)
            }
        }
    } else {
        subdir = "templates"
    }
    file := filepath.Join(chartDir, subdir, filename)
    f, err := os.OpenFile(file, os.O_APPEND|os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0600)
    if err != nil {
        return fmt.Errorf("%w: unable to open %s", err, file)
    }
    defer f.Close()
    for i, t := range templates {
        logrus.WithField("file", file).Debug("writing a template into")
        err = t.Write(f)
        if err != nil {
            return fmt.Errorf("%w: unable to write into %s", err, file)
        }
        if i != len(templates)-1 {
            _, err = f.Write([]byte("\n---\n"))
            if err != nil {
                return fmt.Errorf("%w: unable to write into %s", err, file)
            }
        }
    }
    logrus.WithField("file", file).Info("overwritten")
    return nil
}

func overwriteValuesFile(chartDir string, values helmify.Values, certManagerAsSubchart bool) error {
    if certManagerAsSubchart {
        _, err := values.Add(true, "certmanager", "installCRDs")
        if err != nil {
            return fmt.Errorf("%w: unable to add cert-manager.installCRDs", err)
        }

        _, err = values.Add(true, "certmanager", "enabled")
        if err != nil {
            return fmt.Errorf("%w: unable to add cert-manager.enabled", err)
        }
    }
    res, err := yaml.Marshal(values)
    if err != nil {
        return fmt.Errorf("%w: unable to write marshal values.yaml", err)
    }

    file := filepath.Join(chartDir, "values.yaml")
    err = os.WriteFile(file, res, 0600)
    if err != nil {
        return fmt.Errorf("%w: unable to write values.yaml", err)
    }
    logrus.WithField("file", file).Info("overwritten")
    return nil
}