feat: read helm chart directly from the embedded directory

Signed-off-by: Utku Ozdemir <[email protected]>

Taskfile.yml

@@ -18,13 +18,6 @@ tasks:
       - golangci-lint run ./...
       - helm lint helm/pv-migrate
 
-  update-chart:
-    desc: update the helm chart
-    cmds:
-      - helm-docs -c helm/pv-migrate/
-      - helm package helm/pv-migrate/
-      - mv pv-migrate-*.tgz migrator/helm-chart.tgz
-
   clean:
     desc: clean
     cmds:

helm/helm.go

@@ -0,0 +1,73 @@
+package helm
+
+import (
+	"embed"
+	"fmt"
+	"io/fs"
+	"path/filepath"
+
+	"helm.sh/helm/v3/pkg/chart"
+	"helm.sh/helm/v3/pkg/chart/loader"
+)
+
+// chartFS is the embedded Helm chart.
+//
+// Note: The prefix "all:" is important here, as otherwise the files starting with "." or "_" will be ignored.
+//
+// See: https://github.com/golang/go/issues/44393
+//
+//go:embed all:pv-migrate
+var chartFS embed.FS
+
+const rootDir = "pv-migrate"
+
+// LoadChart loads the embedded Helm chart.
+func LoadChart() (*chart.Chart, error) {
+	files, err := chartAsBufferedFiles()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get chart files: %w", err)
+	}
+
+	helmChart, err := loader.LoadFiles(files)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load chart: %w", err)
+	}
+
+	return helmChart, nil
+}
+
+func chartAsBufferedFiles() ([]*loader.BufferedFile, error) {
+	var files []*loader.BufferedFile
+
+	err := fs.WalkDir(chartFS, rootDir, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if d.IsDir() {
+			return nil
+		}
+
+		data, err := chartFS.ReadFile(path)
+		if err != nil {
+			return fmt.Errorf("failed to read file %q in chart: %w", path, err)
+		}
+
+		relativePath, err := filepath.Rel(rootDir, path)
+		if err != nil {
+			return fmt.Errorf("failed to relativize path %q: %w", path, err)
+		}
+
+		files = append(files, &loader.BufferedFile{
+			Name: relativePath,
+			Data: data,
+		})
+
+		return nil
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to walk chart directory: %w", err)
+	}
+
+	return files, nil
+}

helm/helm_test.go

@@ -0,0 +1,22 @@
+package helm_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/utkuozdemir/pv-migrate/helm"
+)
+
+func TestLoadChart(t *testing.T) {
+	t.Parallel()
+
+	chart, err := helm.LoadChart()
+	require.NoError(t, err)
+
+	assert.Equal(t, "pv-migrate", chart.Metadata.Name)
+	assert.NotEmpty(t, chart.Metadata.Version, "chart version should not be empty")
+	assert.NotEmpty(t, chart.Values, "chart values should not be empty")
+	assert.NotEmpty(t, chart.Templates, "chart templates should not be empty")
+}

migrator/migrator.go

@@ -1,26 +1,21 @@
 package migrator
 
 import (
-	"bytes"
 	"context"
-	_ "embed" // we embed the helm chart
 	"errors"
 	"fmt"
 	"strings"
 
 	log "github.com/sirupsen/logrus"
-	"helm.sh/helm/v3/pkg/chart/loader"
 
+	"github.com/utkuozdemir/pv-migrate/helm"
 	"github.com/utkuozdemir/pv-migrate/k8s"
 	"github.com/utkuozdemir/pv-migrate/migration"
 	"github.com/utkuozdemir/pv-migrate/pvc"
 	"github.com/utkuozdemir/pv-migrate/strategy"
 	"github.com/utkuozdemir/pv-migrate/util"
 )
 
-//go:embed helm-chart.tgz
-var chartBytes []byte
-
 const (
 	attemptIDLength = 5
 )
@@ -97,7 +92,7 @@ func (m *Migrator) Run(ctx context.Context, request *migration.Request) error {
 }
 
 func (m *Migrator) buildMigration(ctx context.Context, request *migration.Request) (*migration.Migration, error) {
-	chart, err := loader.LoadArchive(bytes.NewReader(chartBytes))
+	chart, err := helm.LoadChart()
 	if err != nil {
 		return nil, fmt.Errorf("failed to load helm chart: %w", err)
 	}