build: fix oci-layout named context serialization

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

build/opt.go

@@ -917,29 +917,33 @@ func loadInputs(ctx context.Context, d *driver.DriverHandle, inp *Inputs, pw pro
 		}
 
 		// handle OCI layout
-		if localPath, ok := strings.CutPrefix(v.Path, "oci-layout://"); ok {
+		if ref, ok, err := ocilayout.Parse(v.Path); ok {
-			ref, _, err := ocilayout.Parse("oci-layout://" + localPath)
 			if err != nil {
 				return nil, err
 			}
-			localPath, dig, tag := ref.Path, ref.Digest.String(), ref.Tag
+			localPath := ref.Path
-			if dig == "" {
+
-				dig, err = resolveDigest(localPath, tag)
+			if ref.Digest == "" {
+				dig, err := resolveDigest(localPath, ref.Tag)
 				if err != nil {
 					return nil, errors.Wrapf(err, "oci-layout reference %q could not be resolved", v.Path)
 				}
+				ref.Digest = digest.Digest(dig)
 			}
+
 			store, err := local.NewStore(localPath)
 			if err != nil {
 				return nil, errors.Wrapf(err, "invalid store at %s", localPath)
 			}
+
 			storeName := identity.NewID()
 			if target.OCIStores == nil {
 				target.OCIStores = map[string]content.Store{}
 			}
 			target.OCIStores[storeName] = store
 
-			target.FrontendAttrs["context:"+k] = "oci-layout://" + storeName + ":" + tag + "@" + dig
+			ref.Path = storeName
+			target.FrontendAttrs["context:"+k] = ref.String()
 			continue
 		}
 

build/opt_test.go

@@ -1,10 +1,16 @@
 package build
 
 import (
+	"context"
 	"testing"
 
 	"github.com/docker/buildx/util/buildflags"
+	"github.com/docker/buildx/util/ocilayout"
+	"github.com/docker/buildx/util/progress"
 	"github.com/moby/buildkit/client"
+	"github.com/moby/buildkit/client/ociindex"
+	"github.com/opencontainers/go-digest"
+	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -154,3 +160,91 @@ func TestProxyArgKeyExists(t *testing.T) {
 		})
 	}
 }
+
+func TestLoadInputsOCILayoutNamedContext(t *testing.T) {
+	layoutPath := t.TempDir()
+
+	idx := ociindex.NewStoreIndex(layoutPath)
+	manifestDigest := digest.FromString("manifest")
+	err := idx.Put(ocispecs.Descriptor{
+		MediaType: ocispecs.MediaTypeImageManifest,
+		Digest:    manifestDigest,
+		Size:      1,
+	}, ociindex.Tag("latest"))
+	require.NoError(t, err)
+
+	tests := []struct {
+		name    string
+		ref     string
+		wantRef ocilayout.Ref
+	}{
+		{
+			name: "digest only",
+			ref:  "oci-layout://" + layoutPath + "@" + manifestDigest.String(),
+			wantRef: ocilayout.Ref{
+				Digest: manifestDigest,
+			},
+		},
+		{
+			name: "tag only",
+			ref:  "oci-layout://" + layoutPath + ":latest",
+			wantRef: ocilayout.Ref{
+				Tag:    "latest",
+				Digest: manifestDigest,
+			},
+		},
+		{
+			name: "tag and digest",
+			ref:  "oci-layout://" + layoutPath + ":latest@" + manifestDigest.String(),
+			wantRef: ocilayout.Ref{
+				Tag:    "latest",
+				Digest: manifestDigest,
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			target := &client.SolveOpt{
+				FrontendAttrs: map[string]string{},
+			}
+			inp := &Inputs{
+				ContextPath: "https://example.com/context.tar.gz",
+				NamedContexts: map[string]NamedContext{
+					"proxy": {
+						Path: tt.ref,
+					},
+				},
+			}
+
+			release, err := loadInputs(context.Background(), nil, inp, testProgressWriter{}, target)
+			require.NoError(t, err)
+			require.NotNil(t, release)
+			t.Cleanup(release)
+
+			attr, ok := target.FrontendAttrs["context:proxy"]
+			require.True(t, ok)
+			require.Len(t, target.OCIStores, 1)
+
+			parsed, ok, err := ocilayout.Parse(attr)
+			require.True(t, ok)
+			require.NoError(t, err)
+			require.NotEmpty(t, parsed.Path)
+			assert.Equal(t, tt.wantRef.Tag, parsed.Tag)
+			assert.Equal(t, tt.wantRef.Digest, parsed.Digest)
+			target.OCIStores = nil
+		})
+	}
+}
+
+type testProgressWriter struct{}
+
+func (testProgressWriter) Write(*client.SolveStatus) {}
+
+func (testProgressWriter) WriteBuildRef(string, string) {}
+
+func (testProgressWriter) ValidateLogSource(digest.Digest, any) bool { return true }
+
+func (testProgressWriter) ClearLogSource(any) {}
+
+var _ progress.Writer = testProgressWriter{}

tests/build.go

@@ -1,7 +1,9 @@
 package tests
 
 import (
+	"archive/tar"
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -13,6 +15,8 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/containerd/containerd/v2/core/content"
+	"github.com/containerd/containerd/v2/plugins/content/local"
 	"github.com/containerd/continuity/fs/fstest"
 	"github.com/containerd/platforms"
 	"github.com/creack/pty"
@@ -21,6 +25,7 @@ import (
 	"github.com/docker/buildx/util/gitutil"
 	"github.com/docker/buildx/util/gitutil/gittestutil"
 	"github.com/moby/buildkit/client"
+	"github.com/moby/buildkit/client/ociindex"
 	"github.com/moby/buildkit/frontend/subrequests/lint"
 	"github.com/moby/buildkit/frontend/subrequests/outline"
 	"github.com/moby/buildkit/frontend/subrequests/targets"
@@ -32,6 +37,8 @@ import (
 	"github.com/moby/buildkit/util/testutil"
 	"github.com/moby/buildkit/util/testutil/integration"
 	"github.com/opencontainers/go-digest"
+	"github.com/opencontainers/image-spec/specs-go"
+	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -50,6 +57,7 @@ var buildTests = []func(t *testing.T, sb integration.Sandbox){
 	testBuildStdin,
 	testBuildRemote,
 	testBuildRemoteAuth,
+	testBuildNamedContextOCILayoutDigestOnly,
 	testBuildLocalState,
 	testBuildLocalStateStdin,
 	testBuildLocalStateRemote,
@@ -305,6 +313,35 @@ COPY foo /foo
 	require.FileExists(t, filepath.Join(dirDest, "foo"))
 }
 
+func testBuildNamedContextOCILayoutDigestOnly(t *testing.T, sb integration.Sandbox) {
+	if isMobyWorker(sb) {
+		t.Skip("oci-layout named contexts are not supported by the docker worker")
+	}
+
+	dir := tmpdir(t, fstest.CreateFile("Dockerfile", []byte(`
+FROM scratch
+COPY --from=proxy /foo /foo
+`), 0o600))
+	layoutPath := filepath.Join(dir, "layout")
+	expected := "from-oci-layout"
+	manifestDigest := createOCILayoutImage(t, layoutPath, "foo", []byte(expected), "latest")
+	dirDest := t.TempDir()
+
+	out, err := buildCmd(sb,
+		withDir(dir),
+		withArgs(
+			"--build-context", "proxy=oci-layout://layout@"+manifestDigest.String(),
+			"--output=type=local,dest="+dirDest,
+			dir,
+		),
+	)
+	require.NoError(t, err, out)
+
+	dt, err := os.ReadFile(filepath.Join(dirDest, "foo"))
+	require.NoError(t, err)
+	require.Equal(t, expected, string(dt))
+}
+
 func testBuildLocalState(t *testing.T, sb integration.Sandbox) {
 	dockerfile := []byte(`
 FROM busybox:latest AS base
@@ -1665,3 +1702,76 @@ COPY --from=base /etc/bar /bar
 	)
 	return dir
 }
+
+func createOCILayoutImage(t *testing.T, layoutPath, fileName string, fileContents []byte, tag string) digest.Digest {
+	t.Helper()
+
+	store, err := local.NewStore(layoutPath)
+	require.NoError(t, err)
+
+	layerBytes := bytes.NewBuffer(nil)
+	tw := tar.NewWriter(layerBytes)
+	err = tw.WriteHeader(&tar.Header{
+		Name: fileName,
+		Mode: 0o644,
+		Size: int64(len(fileContents)),
+	})
+	require.NoError(t, err)
+	_, err = tw.Write(fileContents)
+	require.NoError(t, err)
+	require.NoError(t, tw.Close())
+
+	ctx := context.Background()
+	layerDesc := ocispecs.Descriptor{
+		MediaType: ocispecs.MediaTypeImageLayer,
+		Digest:    digest.FromBytes(layerBytes.Bytes()),
+		Size:      int64(layerBytes.Len()),
+	}
+	err = content.WriteBlob(ctx, store, "layer-"+layerDesc.Digest.String(), bytes.NewReader(layerBytes.Bytes()), layerDesc)
+	require.NoError(t, err)
+
+	cfgBytes, err := json.Marshal(ocispecs.Image{
+		Platform: ocispecs.Platform{
+			Architecture: "amd64",
+			OS:           "linux",
+		},
+		Config: ocispecs.ImageConfig{
+			WorkingDir: "/",
+		},
+		RootFS: ocispecs.RootFS{
+			Type:    "layers",
+			DiffIDs: []digest.Digest{layerDesc.Digest},
+		},
+	})
+	require.NoError(t, err)
+	cfgDesc := ocispecs.Descriptor{
+		MediaType: ocispecs.MediaTypeImageConfig,
+		Digest:    digest.FromBytes(cfgBytes),
+		Size:      int64(len(cfgBytes)),
+	}
+	err = content.WriteBlob(ctx, store, "config-"+cfgDesc.Digest.String(), bytes.NewReader(cfgBytes), cfgDesc)
+	require.NoError(t, err)
+
+	manifestBytes, err := json.Marshal(ocispecs.Manifest{
+		Versioned: specs.Versioned{
+			SchemaVersion: 2,
+		},
+		MediaType: ocispecs.MediaTypeImageManifest,
+		Config:    cfgDesc,
+		Layers:    []ocispecs.Descriptor{layerDesc},
+	})
+	require.NoError(t, err)
+	manifestDesc := ocispecs.Descriptor{
+		MediaType: ocispecs.MediaTypeImageManifest,
+		Digest:    digest.FromBytes(manifestBytes),
+		Size:      int64(len(manifestBytes)),
+	}
+	err = content.WriteBlob(ctx, store, "manifest-"+manifestDesc.Digest.String(), bytes.NewReader(manifestBytes), manifestDesc)
+	require.NoError(t, err)
+
+	idx := ociindex.NewStoreIndex(layoutPath)
+	err = idx.Put(manifestDesc, ociindex.Tag(tag))
+	require.NoError(t, err)
+
+	return manifestDesc.Digest
+}

util/imagetools/location.go

@@ -1,8 +1,6 @@
 package imagetools
 
 import (
-	"strings"
-
 	"github.com/distribution/reference"
 	"github.com/docker/buildx/util/ocilayout"
 	digest "github.com/opencontainers/go-digest"
@@ -181,7 +179,3 @@ func (l *Location) ValidateTargetDigest(desc digest.Digest) error {
 	}
 	return nil
 }
-
-func IsOCILayout(s string) bool {
-	return strings.HasPrefix(s, "oci-layout://")
-}