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 {
-			ref, _, err := ocilayout.Parse("oci-layout://" + localPath)
+		if ref, ok, err := ocilayout.Parse(v.Path); ok {
 			if err != nil {
 				return nil, err
 			}
-			localPath, dig, tag := ref.Path, ref.Digest.String(), ref.Tag
-			if dig == "" {
-				dig, err = resolveDigest(localPath, tag)
+			localPath := ref.Path
+
+			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{}