Merge pull request #2061 from Honny1/store-list-layers-images-containers

Create `Store.List` method for listing layers, images, containers

store.go

@@ -84,6 +84,20 @@ type ApplyStagedLayerOptions struct {
 	DiffOptions *drivers.ApplyDiffWithDifferOpts // Mandatory
 }
 
+// MultiListOptions contains options to pass to MultiList
+type MultiListOptions struct {
+	Images     bool // if true, Images will be listed in the result
+	Layers     bool // if true, layers will be listed in the result
+	Containers bool // if true, containers will be listed in the result
+}
+
+// MultiListResult contains slices of Images, Layers or Containers listed by MultiList method
+type MultiListResult struct {
+	Images     []Image
+	Layers     []Layer
+	Containers []Container
+}
+
 // An roBigDataStore wraps up the read-only big-data related methods of the
 // various types of file-based lookaside stores that we implement.
 type roBigDataStore interface {
@@ -561,6 +575,12 @@ type Store interface {
 	// usually by deleting layers and images which are damaged.  If the
 	// right options are set, it will remove containers as well.
 	Repair(report CheckReport, options *RepairOptions) []error
+
+	// MultiList returns a MultiListResult structure that contains layer, image, or container
+	// extracts according to the values in MultiListOptions.
+	// MultiList returns consistent values as of a single point in time.
+	// WARNING: The values may already be out of date by the time they are returned to the caller.
+	MultiList(MultiListOptions) (MultiListResult, error)
 }
 
 // AdditionalLayer represents a layer that is contained in the additional layer store
@@ -3815,3 +3835,55 @@ func (s *store) GarbageCollect() error {
 
 	return firstErr
 }
+
+// List returns a MultiListResult structure that contains layer, image, or container
+// extracts according to the values in MultiListOptions.
+func (s *store) MultiList(options MultiListOptions) (MultiListResult, error) {
+	// TODO: Possible optimization: Deduplicate content from multiple stores.
+	out := MultiListResult{}
+
+	if options.Layers {
+		layerStores, err := s.allLayerStores()
+		if err != nil {
+			return MultiListResult{}, err
+		}
+		for _, roStore := range layerStores {
+			if err := roStore.startReading(); err != nil {
+				return MultiListResult{}, err
+			}
+			defer roStore.stopReading()
+			layers, err := roStore.Layers()
+			if err != nil {
+				return MultiListResult{}, err
+			}
+			out.Layers = append(out.Layers, layers...)
+		}
+	}
+
+	if options.Images {
+		for _, roStore := range s.allImageStores() {
+			if err := roStore.startReading(); err != nil {
+				return MultiListResult{}, err
+			}
+			defer roStore.stopReading()
+
+			images, err := roStore.Images()
+			if err != nil {
+				return MultiListResult{}, err
+			}
+			out.Images = append(out.Images, images...)
+		}
+	}
+
+	if options.Containers {
+		containers, _, err := readContainerStore(s, func() ([]Container, bool, error) {
+			res, err := s.containerStore.Containers()
+			return res, true, err
+		})
+		if err != nil {
+			return MultiListResult{}, err
+		}
+		out.Containers = append(out.Containers, containers...)
+	}
+	return out, nil
+}

store_test.go

@@ -6,33 +6,53 @@ import (
 	"testing"
 
 	"github.com/containers/storage/pkg/idtools"
+	"github.com/containers/storage/pkg/reexec"
 	digest "github.com/opencontainers/go-digest"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
-func TestStore(t *testing.T) {
+func newTestStore(t *testing.T, testOptions StoreOptions) Store {
 	wd := t.TempDir()
 
-	pullOpts := map[string]string{"Test1": "test1", "Test2": "test2"}
-	store, err := GetStore(StoreOptions{
-		RunRoot:            filepath.Join(wd, "run"),
-		GraphRoot:          filepath.Join(wd, "root"),
-		GraphDriverName:    "vfs",
-		GraphDriverOptions: []string{},
-		UIDMap: []idtools.IDMap{{
+	options := testOptions
+	if testOptions.RunRoot == "" {
+		options.RunRoot = filepath.Join(wd, "run")
+	}
+	if testOptions.GraphRoot == "" {
+		options.GraphRoot = filepath.Join(wd, "root")
+	}
+	if testOptions.GraphDriverName == "" {
+		options.GraphDriverName = "vfs"
+	}
+	if testOptions.GraphDriverOptions == nil {
+		options.GraphDriverOptions = []string{}
+	}
+	if len(testOptions.UIDMap) == 0 {
+		options.UIDMap = []idtools.IDMap{{
 			ContainerID: 0,
 			HostID:      os.Getuid(),
 			Size:        1,
-		}},
-		GIDMap: []idtools.IDMap{{
+		}}
+	}
+	if len(testOptions.GIDMap) == 0 {
+		options.GIDMap = []idtools.IDMap{{
 			ContainerID: 0,
 			HostID:      os.Getgid(),
 			Size:        1,
-		}},
+		}}
+	}
+
+	store, err := GetStore(options)
+	require.NoError(t, err)
+	return store
+}
+
+func TestStore(t *testing.T) {
+	pullOpts := map[string]string{"Test1": "test1", "Test2": "test2"}
+	store := newTestStore(t, StoreOptions{
 		PullOptions: pullOpts,
 	})
-	require.NoError(t, err)
 
 	root := store.RunRoot()
 	require.NotNil(t, root)
@@ -52,7 +72,7 @@ func TestStore(t *testing.T) {
 	opts := store.PullOptions()
 	assert.Equal(t, pullOpts, opts)
 
-	_, err = store.GraphDriver()
+	_, err := store.GraphDriver()
 	require.Nil(t, err)
 
 	_, err = store.CreateLayer("foo", "bar", nil, "", false, nil)
@@ -252,25 +272,10 @@ func TestWithSplitStore(t *testing.T) {
 	wd := t.TempDir()
 
 	pullOpts := map[string]string{"Test1": "test1", "Test2": "test2"}
-	store, err := GetStore(StoreOptions{
-		RunRoot:            filepath.Join(wd, "run"),
-		GraphRoot:          filepath.Join(wd, "root"),
-		ImageStore:         filepath.Join(wd, "imgstore"),
-		GraphDriverName:    "vfs",
-		GraphDriverOptions: []string{},
-		UIDMap: []idtools.IDMap{{
-			ContainerID: 0,
-			HostID:      os.Getuid(),
-			Size:        1,
-		}},
-		GIDMap: []idtools.IDMap{{
-			ContainerID: 0,
-			HostID:      os.Getgid(),
-			Size:        1,
-		}},
+	store := newTestStore(t, StoreOptions{
+		ImageStore:  filepath.Join(wd, "imgstore"),
 		PullOptions: pullOpts,
 	})
-	require.NoError(t, err)
 
 	root := store.RunRoot()
 	require.NotNil(t, root)
@@ -290,7 +295,7 @@ func TestWithSplitStore(t *testing.T) {
 	opts := store.PullOptions()
 	assert.Equal(t, pullOpts, opts)
 
-	_, err = store.GraphDriver()
+	_, err := store.GraphDriver()
 	require.Nil(t, err)
 
 	_, err = store.CreateLayer("foo", "bar", nil, "", false, nil)
@@ -485,3 +490,82 @@ func TestWithSplitStore(t *testing.T) {
 	store.Free()
 	store.Free()
 }
+
+func TestStoreMultiList(t *testing.T) {
+	reexec.Init()
+
+	store := newTestStore(t, StoreOptions{})
+
+	_, err := store.CreateLayer("Layer", "", nil, "", false, nil)
+	require.NoError(t, err)
+
+	_, err = store.CreateImage("Image", nil, "Layer", "", nil)
+	require.NoError(t, err)
+
+	_, err = store.CreateContainer("Container", nil, "Image", "", "", nil)
+	require.NoError(t, err)
+
+	tests := []struct {
+		options         MultiListOptions
+		layerCounts     int
+		imageCounts     int
+		containerCounts int
+	}{
+		{
+			options: MultiListOptions{
+				Layers:     true,
+				Images:     true,
+				Containers: true,
+			},
+			layerCounts:     3,
+			imageCounts:     1,
+			containerCounts: 1,
+		},
+
+		{
+			options: MultiListOptions{
+				Layers:     true,
+				Images:     false,
+				Containers: false,
+			},
+			layerCounts:     3,
+			imageCounts:     0,
+			containerCounts: 0,
+		},
+
+		{
+			options: MultiListOptions{
+				Layers:     false,
+				Images:     true,
+				Containers: false,
+			},
+			layerCounts:     0,
+			imageCounts:     1,
+			containerCounts: 0,
+		},
+
+		{
+			options: MultiListOptions{
+				Layers:     false,
+				Images:     false,
+				Containers: true,
+			},
+			layerCounts:     0,
+			imageCounts:     0,
+			containerCounts: 1,
+		},
+	}
+
+	for _, test := range tests {
+		listResults, err := store.MultiList(test.options)
+		require.NoError(t, err)
+		require.Len(t, listResults.Layers, test.layerCounts)
+		require.Len(t, listResults.Images, test.imageCounts)
+		require.Len(t, listResults.Containers, test.containerCounts)
+	}
+
+	_, err = store.Shutdown(true)
+	require.Nil(t, err)
+
+	store.Free()
+}