Function checkLayerFileUpdate

core/snapshots/testsuite/issues.go:43–70

Checks which cover former issues found in older layering models. NOTE: In older models, applying with tar was used to create read only layers, however with the snapshot model read only layers are created just using mounts and commits. Read write layers are a separate type of snapshot which is not c

(ctx context.Context, t *testing.T, sn snapshots.Snapshotter, work string)

// avoid such issues by not relying on tar to create layers.
// See https://github.com/docker/docker/issues/21555
func checkLayerFileUpdate(ctx context.Context, t *testing.T, sn snapshots.Snapshotter, work string) {
	l1Init := fstest.Apply(
		fstest.CreateDir("/etc", 0700),
		fstest.CreateFile("/etc/hosts", []byte("mydomain 10.0.0.1"), 0644),
		fstest.CreateFile("/etc/profile", []byte("PATH=/usr/bin"), 0644),
	)
	l2Init := fstest.Apply(
		fstest.CreateFile("/etc/hosts", []byte("mydomain 10.0.0.2"), 0644),
		fstest.CreateFile("/etc/profile", []byte("PATH=/usr/bin"), 0666),
		fstest.CreateDir("/root", 0700),
		fstest.CreateFile("/root/.bashrc", []byte("PATH=/usr/sbin:/usr/bin"), 0644),
	)

	var sleepTime time.Duration

	// run 5 times to account for sporadic failure
	for range 5 {
		time.Sleep(sleepTime)

		if err := checkSnapshots(ctx, sn, work, l1Init, l2Init); err != nil {
			t.Fatalf("Check snapshots failed: %+v", err)
		}

		// Sleep until next second boundary before running again
		nextTime := time.Now()
		sleepTime = time.Unix(nextTime.Unix()+1, 0).Sub(nextTime)
	}
}

// checkRemoveDirectoryInLowerLayer
// See https://github.com/docker/docker/issues/25244