content-provider: accept v2 piece CID in /piece/<id>

service/contentprovider/http.go

@@ -14,6 +14,7 @@ import (
 	"github.com/data-preservation-programs/singularity/storagesystem"
 	"github.com/data-preservation-programs/singularity/store"
 	"github.com/data-preservation-programs/singularity/util"
+	commcid "github.com/filecoin-project/go-fil-commcid"
 	"github.com/fxamacker/cbor/v2"
 	"github.com/ipfs/boxo/blockservice"
 	"github.com/ipfs/boxo/exchange/offline"
@@ -207,9 +208,9 @@ func getPieceMetadata(ctx context.Context, db *gorm.DB, car model.Car) (*PieceMe
 //   - An error if there was a problem handling the request.
 func GetMetadataHandler(c echo.Context, db *gorm.DB) error {
 	id := c.Param("id")
-	pieceCid, err := cid.Parse(id)
+	pieceCid, err := parsePieceCID(id)
 	if err != nil {
-		return c.String(http.StatusBadRequest, "failed to parse piece CID: "+err.Error())
+		return c.String(http.StatusBadRequest, err.Error())
 	}
 
 	// filter to rows with an attachment -- orphaned cars (attachment_id NULL
@@ -250,6 +251,26 @@ func (s *HTTPServer) getMetadataHandler(c echo.Context) error {
 	return GetMetadataHandler(c, s.dbNoContext.WithContext(c.Request().Context()))
 }
 
+// parsePieceCID accepts either a v1 (FilCommitmentUnsealed multicodec) or
+// v2 (raw multicodec with PieceMh hash carrying CommP + payload size) CID
+// and returns the v1 form. Curio and other FWSS-mediated callers use v2
+// CIDs in their /piece/<cid> URLs; the singularity store still indexes by
+// v1, so we normalize on input.
+func parsePieceCID(id string) (cid.Cid, error) {
+	c, err := cid.Parse(id)
+	if err != nil {
+		return cid.Undef, fmt.Errorf("failed to parse piece CID: %w", err)
+	}
+	if c.Type() == cid.FilCommitmentUnsealed {
+		return c, nil
+	}
+	v1, _, err := commcid.PieceCidV1FromV2(c)
+	if err != nil {
+		return cid.Undef, fmt.Errorf("CID %s is neither v1 commp nor a v2 piece CID: %w", id, err)
+	}
+	return v1, nil
+}
+
 type PieceMetadata struct {
 	Car       model.Car        `cbor:"1,keyasint,omitempty" json:"car"`
 	Storage   model.Storage    `cbor:"2,keyasint,omitempty" json:"storage"`
@@ -383,12 +404,9 @@ func SetCommonHeaders(c echo.Context, pieceCid string) {
 //   - An error if there was a problem handling the request.
 func (s *HTTPServer) handleGetPiece(c echo.Context) error {
 	id := c.Param("id")
-	pieceCid, err := cid.Parse(id)
+	pieceCid, err := parsePieceCID(id)
 	if err != nil {
-		return c.String(http.StatusBadRequest, "failed to parse piece CID: "+err.Error())
-	}
-	if pieceCid.Type() != cid.FilCommitmentUnsealed {
-		return c.String(http.StatusBadRequest, "CID is not a commp")
+		return c.String(http.StatusBadRequest, err.Error())
 	}
 
 	reader, lastModified, err := s.findPiece(c.Request().Context(), pieceCid)

service/contentprovider/http_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/data-preservation-programs/singularity/model"
 	"github.com/data-preservation-programs/singularity/store"
 	"github.com/data-preservation-programs/singularity/util/testutil"
+	commcid "github.com/filecoin-project/go-fil-commcid"
 	"github.com/gotidy/ptr"
 	"github.com/ipfs/boxo/blockservice"
 	"github.com/ipfs/boxo/exchange/offline"
@@ -450,3 +451,38 @@ func TestIPFSGateway_FileChanged(t *testing.T) {
 		require.Equal(t, http.StatusConflict, rec.Code)
 	})
 }
+
+func TestParsePieceCID(t *testing.T) {
+	commD := make([]byte, 32)
+	for i := range commD {
+		commD[i] = byte(i)
+	}
+	v1, err := commcid.DataCommitmentV1ToCID(commD)
+	require.NoError(t, err)
+	require.Equal(t, uint64(cid.FilCommitmentUnsealed), v1.Type())
+
+	// v2 piece CID carrying the same commitment; Curio/FWSS callers use this form
+	v2, err := commcid.PieceCidV2FromV1(v1, 1016)
+	require.NoError(t, err)
+	require.NotEqual(t, v1, v2)
+
+	t.Run("v1 passes through unchanged", func(t *testing.T) {
+		got, err := parsePieceCID(v1.String())
+		require.NoError(t, err)
+		require.Equal(t, v1, got)
+	})
+	t.Run("v2 normalizes to v1", func(t *testing.T) {
+		got, err := parsePieceCID(v2.String())
+		require.NoError(t, err)
+		require.Equal(t, v1, got)
+	})
+	t.Run("non-piece CID is rejected", func(t *testing.T) {
+		raw := cid.NewCidV1(cid.Raw, util.Hash([]byte("not a piece")))
+		_, err := parsePieceCID(raw.String())
+		require.Error(t, err)
+	})
+	t.Run("garbage is rejected", func(t *testing.T) {
+		_, err := parsePieceCID("not-a-cid")
+		require.Error(t, err)
+	})
+}