c8d/save: Add tests

Test saving a shallow/partial image

Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>

daemon/containerd/image_save_test.go

@@ -0,0 +1,103 @@
+package containerd
+
+import (
+	"context"
+	"io"
+	"path/filepath"
+	"testing"
+
+	"github.com/containerd/containerd/namespaces"
+	"github.com/containerd/platforms"
+	"github.com/docker/docker/errdefs"
+	"github.com/docker/docker/internal/testutils/specialimage"
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	"gotest.tools/v3/assert"
+	is "gotest.tools/v3/assert/cmp"
+)
+
+func TestImageMultiplatformSaveShallowWithNative(t *testing.T) {
+	ctx := namespaces.WithNamespace(context.TODO(), "testing-"+t.Name())
+
+	contentDir := t.TempDir()
+	store := &blobsDirContentStore{blobs: filepath.Join(contentDir, "blobs/sha256")}
+
+	native := platforms.Platform{
+		OS:           "linux",
+		Architecture: "amd64",
+	}
+
+	arm64 := platforms.Platform{
+		OS:           "linux",
+		Architecture: "arm64",
+	}
+
+	imgSvc := fakeImageService(t, ctx, store)
+	// Mock the native platform.
+	imgSvc.defaultPlatformOverride = platforms.Only(native)
+
+	idx, _, err := specialimage.PartialMultiPlatform(contentDir, "partial-with-native:latest", specialimage.PartialOpts{
+		Stored:  []ocispec.Platform{native},
+		Missing: []ocispec.Platform{arm64},
+	})
+	assert.NilError(t, err)
+
+	img, err := imgSvc.images.Create(ctx, imagesFromIndex(idx)[0])
+	assert.NilError(t, err)
+
+	t.Run("export without specific platform", func(t *testing.T) {
+		err = imgSvc.ExportImage(ctx, []string{img.Name}, nil, io.Discard)
+		assert.NilError(t, err)
+	})
+	t.Run("export native", func(t *testing.T) {
+		err = imgSvc.ExportImage(ctx, []string{img.Name}, &native, io.Discard)
+		assert.NilError(t, err)
+	})
+	t.Run("export missing", func(t *testing.T) {
+		err = imgSvc.ExportImage(ctx, []string{img.Name}, &arm64, io.Discard)
+		assert.Check(t, is.ErrorType(err, errdefs.IsNotFound))
+	})
+}
+
+func TestImageMultiplatformSaveShallowWithoutNative(t *testing.T) {
+	ctx := namespaces.WithNamespace(context.TODO(), "testing-"+t.Name())
+
+	contentDir := t.TempDir()
+	store := &blobsDirContentStore{blobs: filepath.Join(contentDir, "blobs/sha256")}
+
+	native := platforms.Platform{
+		OS:           "linux",
+		Architecture: "amd64",
+	}
+
+	arm64 := platforms.Platform{
+		OS:           "linux",
+		Architecture: "arm64",
+	}
+
+	imgSvc := fakeImageService(t, ctx, store)
+	// Mock the native platform.
+	imgSvc.defaultPlatformOverride = platforms.Only(native)
+
+	idx, _, err := specialimage.PartialMultiPlatform(contentDir, "partial-without-native:latest", specialimage.PartialOpts{
+		Stored:  []ocispec.Platform{arm64},
+		Missing: []ocispec.Platform{native},
+	})
+	assert.NilError(t, err)
+
+	img, err := imgSvc.images.Create(ctx, imagesFromIndex(idx)[0])
+	assert.NilError(t, err)
+
+	t.Run("export without specific platform", func(t *testing.T) {
+		t.Skip("TODO(vvoland): https://github.com/docker/cli/issues/5476")
+		err = imgSvc.ExportImage(ctx, []string{img.Name}, nil, io.Discard)
+		assert.NilError(t, err)
+	})
+	t.Run("export native", func(t *testing.T) {
+		err = imgSvc.ExportImage(ctx, []string{img.Name}, &native, io.Discard)
+		assert.Check(t, is.ErrorType(err, errdefs.IsNotFound))
+	})
+	t.Run("export arm64", func(t *testing.T) {
+		err = imgSvc.ExportImage(ctx, []string{img.Name}, &arm64, io.Discard)
+		assert.NilError(t, err)
+	})
+}

internal/testutils/specialimage/partial.go

@@ -0,0 +1,56 @@
+package specialimage
+
+import (
+	"github.com/containerd/platforms"
+	"github.com/distribution/reference"
+	"github.com/opencontainers/go-digest"
+	"github.com/opencontainers/image-spec/specs-go"
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+type PartialOpts struct {
+	Stored  []ocispec.Platform
+	Missing []ocispec.Platform
+}
+
+// PartialMultiPlatform creates an index with all platforms in storedPlatforms
+// and missingPlatforms. However, only the blobs of the storedPlatforms are
+// created and stored, while the missingPlatforms are only referenced in the
+// index.
+func PartialMultiPlatform(dir string, imageRef string, opts PartialOpts) (*ocispec.Index, []ocispec.Descriptor, error) {
+	ref, err := reference.ParseNormalizedNamed(imageRef)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var descs []ocispec.Descriptor
+
+	for _, platform := range opts.Stored {
+		ps := platforms.Format(platform)
+		manifestDesc, err := oneLayerPlatformManifest(dir, platform, FileInLayer{Path: "bash", Content: []byte("layer-" + ps)})
+		if err != nil {
+			return nil, nil, err
+		}
+		descs = append(descs, manifestDesc)
+	}
+
+	for _, platform := range opts.Missing {
+		platformStr := platforms.FormatAll(platform)
+		dgst := digest.FromBytes([]byte(platformStr))
+
+		platform := platform
+		descs = append(descs, ocispec.Descriptor{
+			MediaType: ocispec.MediaTypeImageManifest,
+			Size:      128,
+			Platform:  &platform,
+			Digest:    dgst,
+		})
+	}
+
+	idx, err := multiPlatformImage(dir, ref, ocispec.Index{
+		Versioned: specs.Versioned{SchemaVersion: 2},
+		MediaType: ocispec.MediaTypeImageIndex,
+		Manifests: descs,
+	})
+	return idx, descs, err
+}