Merge pull request #887 from tonistiigi/push-by-digest

exporter: allow push by digest in image exporter

client/client_test.go

@@ -33,6 +33,7 @@ import (
 	"github.com/moby/buildkit/session"
 	"github.com/moby/buildkit/session/secrets/secretsprovider"
 	"github.com/moby/buildkit/session/sshforward/sshprovider"
+	"github.com/moby/buildkit/util/contentutil"
 	"github.com/moby/buildkit/util/testutil"
 	"github.com/moby/buildkit/util/testutil/httpserver"
 	"github.com/moby/buildkit/util/testutil/integration"
@@ -85,6 +86,7 @@ func TestClientIntegration(t *testing.T) {
 		testSSHMount,
 		testStdinClosed,
 		testHostnameLookup,
+		testPushByDigest,
 		testBasicInlineCacheImportExport,
 		testExportBusyboxLocal,
 	},
@@ -373,6 +375,50 @@ func testNetworkMode(t *testing.T, sb integration.Sandbox) {
 	require.Contains(t, err.Error(), "network.host is not allowed")
 }
 
+func testPushByDigest(t *testing.T, sb integration.Sandbox) {
+	requiresLinux(t)
+	c, err := New(context.TODO(), sb.Address())
+	require.NoError(t, err)
+	defer c.Close()
+
+	registry, err := sb.NewRegistry()
+	if errors.Cause(err) == integration.ErrorRequirements {
+		t.Skip(err.Error())
+	}
+	require.NoError(t, err)
+
+	st := llb.Scratch().File(llb.Mkfile("foo", 0600, []byte("data")))
+
+	def, err := st.Marshal()
+	require.NoError(t, err)
+
+	name := registry + "/foo/bar"
+
+	resp, err := c.Solve(context.TODO(), def, SolveOpt{
+		Exports: []ExportEntry{
+			{
+				Type: "image",
+				Attrs: map[string]string{
+					"name":           name,
+					"push":           "true",
+					"push-by-digest": "true",
+				},
+			},
+		},
+	}, nil)
+	require.NoError(t, err)
+
+	_, _, err = contentutil.ProviderFromRef(name + ":latest")
+	require.Error(t, err)
+
+	desc, _, err := contentutil.ProviderFromRef(name + "@" + resp.ExporterResponse["containerimage.digest"])
+	require.NoError(t, err)
+
+	require.Equal(t, resp.ExporterResponse["containerimage.digest"], desc.Digest.String())
+	require.Equal(t, images.MediaTypeDockerSchema2Manifest, desc.MediaType)
+	require.True(t, desc.Size > 0)
+}
+
 func testFrontendImageNaming(t *testing.T, sb integration.Sandbox) {
 	requiresLinux(t)
 	c, err := New(context.TODO(), sb.Address())

exporter/containerimage/export.go

@@ -16,10 +16,11 @@ import (
 )
 
 const (
-	keyImageName = "name"
-	keyPush      = "push"
-	keyInsecure  = "registry.insecure"
-	ociTypes     = "oci-mediatypes"
+	keyImageName    = "name"
+	keyPush         = "push"
+	keyPushByDigest = "push-by-digest"
+	keyInsecure     = "registry.insecure"
+	ociTypes        = "oci-mediatypes"
 )
 
 type Opt struct {
@@ -58,6 +59,16 @@ func (e *imageExporter) Resolve(ctx context.Context, opt map[string]string) (exp
 				return nil, errors.Wrapf(err, "non-bool value specified for %s", k)
 			}
 			i.push = b
+		case keyPushByDigest:
+			if v == "" {
+				i.pushByDigest = true
+				continue
+			}
+			b, err := strconv.ParseBool(v)
+			if err != nil {
+				return nil, errors.Wrapf(err, "non-bool value specified for %s", k)
+			}
+			i.pushByDigest = b
 		case keyInsecure:
 			if v == "" {
 				i.insecure = true
@@ -90,11 +101,12 @@ func (e *imageExporter) Resolve(ctx context.Context, opt map[string]string) (exp
 
 type imageExporterInstance struct {
 	*imageExporter
-	targetName string
-	push       bool
-	insecure   bool
-	ociTypes   bool
-	meta       map[string][]byte
+	targetName   string
+	push         bool
+	pushByDigest bool
+	insecure     bool
+	ociTypes     bool
+	meta         map[string][]byte
 }
 
 func (e *imageExporterInstance) Name() string {
@@ -146,7 +158,7 @@ func (e *imageExporterInstance) Export(ctx context.Context, src exporter.Source)
 				tagDone(nil)
 			}
 			if e.push {
-				if err := push.Push(ctx, e.opt.SessionManager, e.opt.ImageWriter.ContentStore(), desc.Digest, targetName, e.insecure, e.opt.ResolverOpt); err != nil {
+				if err := push.Push(ctx, e.opt.SessionManager, e.opt.ImageWriter.ContentStore(), desc.Digest, targetName, e.insecure, e.opt.ResolverOpt, e.pushByDigest); err != nil {
 					return nil, err
 				}
 			}

util/push/push.go

@@ -19,6 +19,7 @@ import (
 	"github.com/moby/buildkit/util/resolver"
 	digest "github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
@@ -40,7 +41,7 @@ func getCredentialsFunc(ctx context.Context, sm *session.Manager) func(string) (
 	}
 }
 
-func Push(ctx context.Context, sm *session.Manager, cs content.Provider, dgst digest.Digest, ref string, insecure bool, rfn resolver.ResolveOptionsFunc) error {
+func Push(ctx context.Context, sm *session.Manager, cs content.Provider, dgst digest.Digest, ref string, insecure bool, rfn resolver.ResolveOptionsFunc, byDigest bool) error {
 	desc := ocispec.Descriptor{
 		Digest: dgst,
 	}
@@ -48,7 +49,15 @@ func Push(ctx context.Context, sm *session.Manager, cs content.Provider, dgst di
 	if err != nil {
 		return err
 	}
-	ref = reference.TagNameOnly(parsed).String()
+	if byDigest && !reference.IsNameOnly(parsed) {
+		return errors.Errorf("can't push tagged ref %s by digest", parsed.String())
+	}
+
+	if byDigest {
+		ref = parsed.Name()
+	} else {
+		ref = reference.TagNameOnly(parsed).String()
+	}
 
 	opt := rfn(ref)
 	opt.Credentials = getCredentialsFunc(ctx, sm)