Add containerd migration to daemon startup

Add layer migration on startup
Use image size threshold rather than image count
Add daemon integration test
Add test for migrating to containerd snapshotters
Add vfs migration
Add tar export for containerd migration
Add containerd migration test with save and load

Signed-off-by: Derek McGowan <derek@mcg.dev>

integration/daemon/migration_test.go

@@ -0,0 +1,159 @@
+package daemon // import "github.com/docker/docker/integration/daemon"
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"runtime"
+	"testing"
+
+	containertypes "github.com/moby/moby/api/types/container"
+	"github.com/moby/moby/api/types/image"
+	"github.com/moby/moby/v2/integration/internal/container"
+	"github.com/moby/moby/v2/testutil"
+	"github.com/moby/moby/v2/testutil/daemon"
+	"github.com/moby/moby/v2/testutil/fixtures/load"
+	"gotest.tools/v3/assert"
+	"gotest.tools/v3/skip"
+)
+
+func TestMigrateOverlaySnapshotter(t *testing.T) {
+	testMigrateSnapshotter(t, "overlay2", "overlayfs")
+}
+
+func TestMigrateNativeSnapshotter(t *testing.T) {
+	testMigrateSnapshotter(t, "vfs", "native")
+}
+
+func testMigrateSnapshotter(t *testing.T, graphdriver, snapshotter string) {
+	skip.If(t, runtime.GOOS != "linux")
+	skip.If(t, os.Getenv("TEST_INTEGRATION_USE_SNAPSHOTTER") != "")
+
+	ctx := testutil.StartSpan(baseContext, t)
+
+	d := daemon.New(t)
+	defer d.Stop(t)
+
+	d.Start(t, "--iptables=false", "--ip6tables=false", "-s", graphdriver)
+	info := d.Info(t)
+	id := info.ID
+	assert.Check(t, id != "")
+	assert.Equal(t, info.Containers, 0)
+	assert.Equal(t, info.Images, 0)
+	assert.Equal(t, info.Driver, graphdriver)
+
+	load.FrozenImagesLinux(ctx, d.NewClientT(t), "busybox:latest")
+
+	info = d.Info(t)
+	allImages := info.Images
+	assert.Check(t, allImages > 0)
+
+	apiClient := d.NewClientT(t)
+
+	containerID := container.Run(ctx, t, apiClient, func(c *container.TestContainerConfig) {
+		c.Name = "Migration-1-" + snapshotter
+		c.Config.Image = "busybox:latest"
+		c.Config.Cmd = []string{"top"}
+	})
+
+	d.Stop(t)
+
+	// Start with migration feature but with a container which will prevent migration
+	d.Start(t, "--iptables=false", "--ip6tables=false", "-s", graphdriver, "--feature", "containerd-migration")
+	info = d.Info(t)
+	assert.Equal(t, info.ID, id)
+	assert.Equal(t, info.Driver, graphdriver)
+	assert.Equal(t, info.Containers, 1)
+	assert.Equal(t, info.Images, allImages)
+	container.Remove(ctx, t, apiClient, containerID, containertypes.RemoveOptions{
+		Force: true,
+	})
+
+	d.Stop(t)
+
+	d.Start(t, "--iptables=false", "--ip6tables=false", "-s", graphdriver, "--feature", "containerd-migration")
+	info = d.Info(t)
+	assert.Equal(t, info.ID, id)
+	assert.Equal(t, info.Containers, 0)
+	assert.Equal(t, info.Driver, snapshotter, "expected migrate to switch from %s to %s", graphdriver, snapshotter)
+	assert.Equal(t, info.Images, allImages)
+
+	result := container.RunAttach(ctx, t, apiClient, func(c *container.TestContainerConfig) {
+		c.Name = "Migration-2-" + snapshotter
+		c.Config.Image = "busybox:latest"
+		c.Config.Cmd = []string{"echo", "hello"}
+	})
+	assert.Equal(t, result.ExitCode, 0)
+	container.Remove(ctx, t, apiClient, result.ContainerID, containertypes.RemoveOptions{})
+}
+
+func TestMigrateSaveLoad(t *testing.T) {
+	skip.If(t, runtime.GOOS != "linux")
+	skip.If(t, os.Getenv("TEST_INTEGRATION_USE_SNAPSHOTTER") != "")
+
+	var (
+		ctx         = testutil.StartSpan(baseContext, t)
+		d           = daemon.New(t)
+		graphdriver = "overlay2"
+		snapshotter = "overlayfs"
+	)
+	defer d.Stop(t)
+
+	d.Start(t, "--iptables=false", "--ip6tables=false", "-s", graphdriver)
+	info := d.Info(t)
+	id := info.ID
+	assert.Check(t, id != "")
+	assert.Equal(t, info.Containers, 0)
+	assert.Equal(t, info.Images, 0)
+	assert.Equal(t, info.Driver, graphdriver)
+
+	load.FrozenImagesLinux(ctx, d.NewClientT(t), "busybox:latest")
+
+	info = d.Info(t)
+	allImages := info.Images
+	assert.Check(t, allImages > 0)
+
+	d.Stop(t)
+
+	d.Start(t, "--iptables=false", "--ip6tables=false", "-s", graphdriver, "--feature", "containerd-migration")
+	info = d.Info(t)
+	assert.Equal(t, info.ID, id)
+	assert.Equal(t, info.Containers, 0)
+	assert.Equal(t, info.Driver, snapshotter, "expected migrate to switch from %s to %s", graphdriver, snapshotter)
+	assert.Equal(t, info.Images, allImages)
+
+	apiClient := d.NewClientT(t)
+
+	// Save image to buffer
+	rdr, err := apiClient.ImageSave(ctx, []string{"busybox:latest"}, image.SaveOptions{})
+	assert.NilError(t, err)
+	buf := bytes.NewBuffer(nil)
+	io.Copy(buf, rdr)
+	rdr.Close()
+
+	// Delete all images
+	list, err := apiClient.ImageList(ctx, image.ListOptions{})
+	assert.NilError(t, err)
+	for _, i := range list {
+		_, err = apiClient.ImageRemove(ctx, i.ID, image.RemoveOptions{})
+		assert.NilError(t, err)
+	}
+
+	// Check zero images
+	info = d.Info(t)
+	assert.Equal(t, info.Images, 0)
+
+	// Import
+	lr, err := apiClient.ImageLoad(ctx, bytes.NewReader(buf.Bytes()), image.LoadOptions{Quiet: true})
+	assert.NilError(t, err)
+	io.Copy(io.Discard, lr.Body)
+	lr.Body.Close()
+
+	result := container.RunAttach(ctx, t, apiClient, func(c *container.TestContainerConfig) {
+		c.Name = "Migration-save-load-" + snapshotter
+		c.Config.Image = "busybox:latest"
+		c.Config.Cmd = []string{"echo", "hello"}
+	})
+	assert.Equal(t, result.ExitCode, 0)
+	container.Remove(ctx, t, apiClient, result.ContainerID, containertypes.RemoveOptions{})
+}