feat: allow ValuesFile from GCS

pkg/skaffold/gcs/gsutil.go

@@ -38,10 +38,19 @@ import (
 
 const GsutilExec = "gsutil"
 
-type Gsutil struct{}
+type Gsutil interface {
+	Copy(ctx context.Context, src, dst string, recursive bool) error
+}
+
+type gsutil struct{}
+
+// NewGsutil returns a gsutil client.
+func NewGsutil() Gsutil {
+	return &gsutil{}
+}
 
 // Copy calls `gsutil cp [-r] <source_url> <destination_url>
-func (g *Gsutil) Copy(ctx context.Context, src, dst string, recursive bool) error {
+func (g *gsutil) Copy(ctx context.Context, src, dst string, recursive bool) error {
 	args := []string{"cp"}
 	if recursive {
 		args = append(args, "-r")

pkg/skaffold/gcs/gsutil_test.go

@@ -69,7 +69,7 @@ func TestCopy(t *testing.T) {
 		testutil.Run(t, test.description, func(t *testutil.T) {
 			t.Override(&util.DefaultExecCommand, test.commands)
 
-			gcs := Gsutil{}
+			gcs := NewGsutil()
 			err := gcs.Copy(context.Background(), test.src, test.dst, test.recursive)
 
 			t.CheckError(test.shouldErr, err)

pkg/skaffold/helm/args.go

@@ -19,6 +19,9 @@ package helm
 import (
 	"context"
 	"fmt"
+	"os"
+	"path"
+	"path/filepath"
 	"runtime"
 	"strconv"
 	"strings"
@@ -27,13 +30,19 @@ import (
 
 	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/constants"
 	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/docker"
+	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/gcs"
 	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/graph"
 	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/output/log"
 	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/schema/latest"
 	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/util"
 	maps "github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/util/map"
 )
 
+const (
+	gcsPrefix        = "gs://"
+	valueFileFromGCS = "valuefiles_from_gcs"
+)
+
 // ConstructOverrideArgs creates the command line arguments for overrides
 func ConstructOverrideArgs(r *latest.HelmRelease, builds []graph.Artifact, args []string, manifestOverrides map[string]string) ([]string, error) {
 	for _, k := range maps.SortKeys(r.SetValues) {
@@ -85,8 +94,26 @@ func ConstructOverrideArgs(r *latest.HelmRelease, builds []graph.Artifact, args
 		args = append(args, "--set", fmt.Sprintf("%s=%s", expandedKey, v))
 	}
 
+	gcs := gcs.NewGsutil()
+
 	for _, v := range r.ValuesFiles {
-		exp, err := homedir.Expand(v)
+		tempValueFile := v
+
+		// if the file starts with gs:// then download it in tmp dir
+		if strings.HasPrefix(v, gcsPrefix) {
+			tempDir, err := os.MkdirTemp("", valueFileFromGCS)
+			if err != nil {
+				return nil, fmt.Errorf("failed to create the tmp directory: %w", err)
+			}
+
+			if extractedFilePath, err := extractValueFileFromGCS(v, tempDir, gcs); err != nil {
+				return nil, err
+			} else {
+				tempValueFile = extractedFilePath
+			}
+		}
+
+		exp, err := homedir.Expand(tempValueFile)
 		if err != nil {
 			return nil, fmt.Errorf("unable to expand %q: %w", v, err)
 		}
@@ -151,3 +178,15 @@ func envVarForImage(imageName string, digest string) map[string]string {
 	customMap["IMAGE_FULLY_QUALIFIED"] = digest
 	return customMap
 }
+
+// Copy the value file from the GCS bucket if it starts with gs://
+func extractValueFileFromGCS(v, tempDir string, gcs gcs.Gsutil) (string, error) {
+	// get a filename from gcs
+	tempValueFile := filepath.Join(tempDir, path.Base(v))
+
+	if err := gcs.Copy(context.TODO(), v, tempValueFile, false); err != nil {
+		return "", fmt.Errorf("failed to copy valuesFile from GCS: %w", err)
+	}
+
+	return tempValueFile, nil
+}

pkg/skaffold/helm/args_test.go

@@ -17,6 +17,10 @@ limitations under the License.
 package helm
 
 import (
+	"context"
+	"fmt"
+	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/GoogleContainerTools/skaffold/v2/testutil"
@@ -122,3 +126,57 @@ func TestSanitizeFilePath(t *testing.T) {
 		})
 	}
 }
+
+// MockGsutil implements gcs.Gsutil with a controlled Copy method
+type mockGsutil struct{}
+
+// Copy extracts the filename and returns success or failure based on the filename.
+func (m *mockGsutil) Copy(ctx context.Context, src string, dst string, recursive bool) error {
+	// Extract the filename from the source path
+	filename := filepath.Base(src)
+
+	// If the filename contains "not_exist", return an error (simulate failure)
+	if strings.Contains(filename, "not_exist") {
+		return fmt.Errorf("file not found: %s", src)
+	}
+
+	// Otherwise, return success
+	return nil
+}
+
+func TestExtractValueFileFromGCS(t *testing.T) {
+	tempDir := t.TempDir()
+
+	tests := []struct {
+		description string
+		src         string
+		dst         string
+		shouldErr   bool
+	}{
+		{
+			description: "copy file from GCS",
+			src:         "gs://bucket/path/to/values.yaml",
+			dst:         filepath.Join(tempDir, "values.yaml"),
+			shouldErr:   false,
+		},
+		{
+			description: "fail to copy file from GCS",
+			src:         "gs://bucket/path/to/not_exist_values.yaml",
+			dst:         filepath.Join(tempDir, "not_exist_values.yaml"),
+			shouldErr:   true,
+		},
+	}
+
+	for _, test := range tests {
+		testutil.Run(t, test.description, func(t *testutil.T) {
+			result, err := extractValueFileFromGCS(test.src, tempDir, &mockGsutil{})
+			// Check if the error status matches the expected result
+			t.CheckError(test.shouldErr, err)
+
+			// If no error, validate the copied file path
+			if err == nil {
+				t.CheckDeepEqual(result, test.dst)
+			}
+		})
+	}
+}