containerd/snapshot/btrfs/btrfs_test.go
Stephen J Day b1a70aa335
snapshot/storage: namespace snapshot drivers
Signed-off-by: Stephen J Day <stephen.day@docker.com>
2017-06-08 12:29:26 -07:00

280 lines
7.3 KiB
Go

// +build linux
package btrfs
import (
"context"
"io/ioutil"
"os"
"os/exec"
"path/filepath"
"strings"
"testing"
"github.com/containerd/containerd/mount"
"github.com/containerd/containerd/namespaces"
"github.com/containerd/containerd/snapshot"
"github.com/containerd/containerd/snapshot/testsuite"
"github.com/containerd/containerd/testutil"
)
const (
mib = 1024 * 1024
)
func boltSnapshotter(t *testing.T) func(context.Context, string) (snapshot.Snapshotter, func(), error) {
return func(ctx context.Context, root string) (snapshot.Snapshotter, func(), error) {
device := setupBtrfsLoopbackDevice(t, root)
snapshotter, err := NewSnapshotter(root)
if err != nil {
t.Fatal(err)
}
return snapshotter, func() {
device.remove(t)
}, nil
}
}
func TestBtrfs(t *testing.T) {
testutil.RequiresRoot(t)
testsuite.SnapshotterSuite(t, "Btrfs", boltSnapshotter(t))
}
func TestBtrfsMounts(t *testing.T) {
testutil.RequiresRoot(t)
ctx := namespaces.WithNamespace(context.Background(), "snapshotter-btrfs-test")
// create temporary directory for mount point
mountPoint, err := ioutil.TempDir("", "containerd-btrfs-test")
if err != nil {
t.Fatal("could not create mount point for btrfs test", err)
}
defer os.RemoveAll(mountPoint)
t.Log("temporary mount point created", mountPoint)
root, err := ioutil.TempDir(mountPoint, "TestBtrfsPrepare-")
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(root)
b, c, err := boltSnapshotter(t)(ctx, root)
if err != nil {
t.Fatal(err)
}
defer c()
target := filepath.Join(root, "test")
mounts, err := b.Prepare(ctx, target, "")
if err != nil {
t.Fatal(err)
}
t.Log(mounts)
for _, mount := range mounts {
if mount.Type != "btrfs" {
t.Fatalf("wrong mount type: %v != btrfs", mount.Type)
}
// assumes the first, maybe incorrect in the future
if !strings.HasPrefix(mount.Options[0], "subvolid=") {
t.Fatalf("no subvolid option in %v", mount.Options)
}
}
if err := os.MkdirAll(target, 0755); err != nil {
t.Fatal(err)
}
if err := mount.MountAll(mounts, target); err != nil {
t.Fatal(err)
}
defer testutil.Unmount(t, target)
// write in some data
if err := ioutil.WriteFile(filepath.Join(target, "foo"), []byte("content"), 0777); err != nil {
t.Fatal(err)
}
// TODO(stevvooe): We don't really make this with the driver, but that
// might prove annoying in practice.
if err := os.MkdirAll(filepath.Join(root, "snapshots"), 0755); err != nil {
t.Fatal(err)
}
if err := b.Commit(ctx, filepath.Join(root, "snapshots/committed"), filepath.Join(root, "test")); err != nil {
t.Fatal(err)
}
target = filepath.Join(root, "test2")
mounts, err = b.Prepare(ctx, target, filepath.Join(root, "snapshots/committed"))
if err != nil {
t.Fatal(err)
}
if err := os.MkdirAll(target, 0755); err != nil {
t.Fatal(err)
}
if err := mount.MountAll(mounts, target); err != nil {
t.Fatal(err)
}
defer testutil.Unmount(t, target)
// TODO(stevvooe): Verify contents of "foo"
if err := ioutil.WriteFile(filepath.Join(target, "bar"), []byte("content"), 0777); err != nil {
t.Fatal(err)
}
if err := b.Commit(ctx, filepath.Join(root, "snapshots/committed2"), target); err != nil {
t.Fatal(err)
}
}
type testDevice struct {
mountPoint string
fileName string
deviceName string
}
// setupBtrfsLoopbackDevice creates a file, mounts it as a loopback device, and
// formats it as btrfs. The device should be cleaned up by calling
// removeBtrfsLoopbackDevice.
func setupBtrfsLoopbackDevice(t *testing.T, mountPoint string) *testDevice {
// create temporary file for the disk image
file, err := ioutil.TempFile("", "containerd-btrfs-test")
if err != nil {
t.Fatal("Could not create temporary file for btrfs test", err)
}
t.Log("Temporary file created", file.Name())
// initialize file with 100 MiB
if err := file.Truncate(100 << 20); err != nil {
t.Fatal(err)
}
file.Close()
// create device
losetup := exec.Command("losetup", "--find", "--show", file.Name())
p, err := losetup.Output()
if err != nil {
t.Fatal(err)
}
deviceName := strings.TrimSpace(string(p))
t.Log("Created loop device", deviceName)
// format
t.Log("Creating btrfs filesystem")
mkfs := exec.Command("mkfs.btrfs", deviceName)
err = mkfs.Run()
if err != nil {
t.Fatal("Could not run mkfs.btrfs", err)
}
// mount
t.Logf("Mounting %s at %s", deviceName, mountPoint)
mount := exec.Command("mount", deviceName, mountPoint)
err = mount.Run()
if err != nil {
t.Fatal("Could not mount", err)
}
return &testDevice{
mountPoint: mountPoint,
fileName: file.Name(),
deviceName: deviceName,
}
}
// remove cleans up the test device, unmounting the loopback and disk image
// file.
func (device *testDevice) remove(t *testing.T) {
// unmount
testutil.Unmount(t, device.mountPoint)
// detach device
t.Log("Removing loop device")
losetup := exec.Command("losetup", "--detach", device.deviceName)
err := losetup.Run()
if err != nil {
t.Error("Could not remove loop device", device.deviceName, err)
}
// remove file
t.Log("Removing temporary file")
err = os.Remove(device.fileName)
if err != nil {
t.Error(err)
}
// remove mount point
t.Log("Removing temporary mount point")
err = os.RemoveAll(device.mountPoint)
if err != nil {
t.Error(err)
}
}
func TestGetBtrfsDevice(t *testing.T) {
testCases := []struct {
expectedDevice string
expectedError string
root string
mounts []mount.Info
}{
{
expectedDevice: "/dev/loop0",
root: "/var/lib/containerd/snapshot/btrfs",
mounts: []mount.Info{
{Root: "/", Mountpoint: "/", FSType: "ext4", Source: "/dev/sda1"},
{Root: "/", Mountpoint: "/var/lib/containerd/snapshot/btrfs", FSType: "btrfs", Source: "/dev/loop0"},
},
},
{
expectedError: "/var/lib/containerd/snapshot/btrfs is not mounted as btrfs",
root: "/var/lib/containerd/snapshot/btrfs",
mounts: []mount.Info{
{Root: "/", Mountpoint: "/", FSType: "ext4", Source: "/dev/sda1"},
},
},
{
expectedDevice: "/dev/sda1",
root: "/var/lib/containerd/snapshot/btrfs",
mounts: []mount.Info{
{Root: "/", Mountpoint: "/", FSType: "btrfs", Source: "/dev/sda1"},
},
},
{
expectedDevice: "/dev/sda2",
root: "/var/lib/containerd/snapshot/btrfs",
mounts: []mount.Info{
{Root: "/", Mountpoint: "/", FSType: "btrfs", Source: "/dev/sda1"},
{Root: "/", Mountpoint: "/var/lib/containerd/snapshot/btrfs", FSType: "btrfs", Source: "/dev/sda2"},
},
},
{
expectedDevice: "/dev/sda2",
root: "/var/lib/containerd/snapshot/btrfs",
mounts: []mount.Info{
{Root: "/", Mountpoint: "/var/lib/containerd/snapshot/btrfs", FSType: "btrfs", Source: "/dev/sda2"},
{Root: "/", Mountpoint: "/var/lib/foooooooooooooooooooo/baaaaaaaaaaaaaaaaaaaar", FSType: "btrfs", Source: "/dev/sda3"}, // mountpoint length longer than /var/lib/containerd/snapshot/btrfs
{Root: "/", Mountpoint: "/", FSType: "btrfs", Source: "/dev/sda1"},
},
},
}
for i, tc := range testCases {
device, err := getBtrfsDevice(tc.root, tc.mounts)
if err != nil && tc.expectedError == "" {
t.Fatalf("%d: expected nil, got %v", i, err)
}
if err != nil && !strings.Contains(err.Error(), tc.expectedError) {
t.Fatalf("%d: expected %s, got %v", i, tc.expectedError, err)
}
if err == nil && device != tc.expectedDevice {
t.Fatalf("%d: expected %s, got %s", i, tc.expectedDevice, device)
}
}
}