Create file locking directory if it does not exist (#6555)

* Create file locking directory if it does not exist

As Helm v3 uses lazy creation for configuration then
directories and files are not created until required.
File locking when doing repo add was introduced in
v2 and ported to v3 in #6492. It locks on the config
directory where the repo file resides and therefore
needs the directory to be created if it doesn't exist.
This fix adds the directory if need be,

Signed-off-by: Martin Hickey <martin.hickey@ie.ibm.com>

* Add unit test

Signed-off-by: Martin Hickey <martin.hickey@ie.ibm.com>

cmd/helm/repo_add.go

@@ -22,6 +22,7 @@ import (
 	"io"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"time"
 
 	"github.com/gofrs/flock"
@@ -78,6 +79,12 @@ func newRepoAddCmd(out io.Writer) *cobra.Command {
 }
 
 func (o *repoAddOptions) run(out io.Writer) error {
+	//Ensure the file directory exists as it is required for file locking
+	err := os.MkdirAll(filepath.Dir(o.repoFile), os.ModePerm)
+	if err != nil && !os.IsExist(err) {
+		return err
+	}
+
 	// Lock the repository file for concurrent goroutines or processes synchronization
 	fileLock := flock.New(o.repoFile)
 	lockCtx, cancel := context.WithTimeout(context.Background(), 30*time.Second)

cmd/helm/repo_add_test.go

@@ -92,15 +92,23 @@ func TestRepoAdd(t *testing.T) {
 
 func TestRepoAddConcurrentGoRoutines(t *testing.T) {
 	const testName = "test-name"
+	repoFile := filepath.Join(ensure.TempDir(t), "repositories.yaml")
+	repoAddConcurrent(t, testName, repoFile)
+}
+
+func TestRepoAddConcurrentDirNotExist(t *testing.T) {
+	const testName = "test-name-2"
+	repoFile := filepath.Join(ensure.TempDir(t), "foo", "repositories.yaml")
+	repoAddConcurrent(t, testName, repoFile)
+}
 
+func repoAddConcurrent(t *testing.T, testName, repoFile string) {
 	ts, err := repotest.NewTempServer("testdata/testserver/*.*")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer ts.Stop()
 
-	repoFile := filepath.Join(ensure.TempDir(t), "repositories.yaml")
-
 	var wg sync.WaitGroup
 	wg.Add(3)
 	for i := 0; i < 3; i++ {