Function TestParallelDownloadTo

pkg/downloader/chart_downloader_windows_test.go:34–131

TestParallelDownloadTo tests that parallel downloads to the same file don't cause "Access Denied" errors on Windows. This test is Windows-specific because the file locking behavior is only needed on Windows.

(t *testing.T)

// don't cause "Access Denied" errors on Windows. This test is Windows-specific
// because the file locking behavior is only needed on Windows.
func TestParallelDownloadTo(t *testing.T) {
	// Set up a simple test server with a chart
	srv := repotest.NewTempServer(t, repotest.WithChartSourceGlob("testdata/*.tgz"))
	defer srv.Stop()

	if err := srv.CreateIndex(); err != nil {
		t.Fatal(err)
	}

	dest := t.TempDir()
	cacheDir := t.TempDir()

	c := ChartDownloader{
		Out:              os.Stderr,
		RepositoryConfig: repoConfig,
		RepositoryCache:  repoCache,
		ContentCache:     cacheDir,
		Cache:            &DiskCache{Root: cacheDir},
		Getters: getter.All(&cli.EnvSettings{
			RepositoryConfig: repoConfig,
			RepositoryCache:  repoCache,
			ContentCache:     cacheDir,
		}),
	}

	// Use a direct URL to bypass repository lookup
	chartURL := srv.URL() + "/local-subchart-0.1.0.tgz"

	// Number of parallel downloads to attempt
	numDownloads := 10
	var wg sync.WaitGroup
	errors := make([]error, numDownloads)

	// Launch multiple goroutines to download the same chart simultaneously
	for i := 0; i < numDownloads; i++ {
		wg.Add(1)
		go func(index int) {
			defer wg.Done()
			_, _, err := c.DownloadTo(chartURL, "", dest)
			errors[index] = err
		}(i)
	}

	wg.Wait()

	// Check if any download failed
	failedCount := 0
	for i, err := range errors {
		if err != nil {
			t.Logf("Download %d failed: %v", i, err)
			failedCount++
		}
	}

	// With the file locking fix, all parallel downloads should succeed
	if failedCount > 0 {
		t.Errorf("Parallel downloads failed: %d out of %d downloads failed due to concurrent file access", failedCount, numDownloads)
	}