PeerDAS: Implement DAS (#15367)

* PeerDAS: Implement DAS

* Fix Terence's comment.

* Fix Terence comment.

* Fix Terence's comment.

* Fix James' comment.

* Fix James' comment.

* Rename some variable/files with blobs.

* Fix James' comment.

* Fix James' comment.

* Fix James' comment.

consensus-types/blocks/BUILD.bazel

@@ -13,6 +13,7 @@ go_library(
         "roblob.go",
         "roblock.go",
         "rodatacolumn.go",
+        "rosidecar.go",
         "setters.go",
         "types.go",
     ],
@@ -53,6 +54,7 @@ go_test(
         "roblob_test.go",
         "roblock_test.go",
         "rodatacolumn_test.go",
+        "rosidecar_test.go",
     ],
     embed = [":go_default_library"],
     deps = [
@@ -72,5 +74,6 @@ go_test(
         "@com_github_prysmaticlabs_fastssz//:go_default_library",
         "@com_github_prysmaticlabs_go_bitfield//:go_default_library",
         "@com_github_prysmaticlabs_gohashtree//:go_default_library",
+        "@com_github_stretchr_testify//require:go_default_library",
     ],
 )

consensus-types/blocks/rosidecar.go

@@ -0,0 +1,96 @@
+package blocks
+
+import (
+	"github.com/pkg/errors"
+)
+
+// ROSidecar represents a read-only sidecar with its block root.
+type ROSidecar struct {
+	blob       *ROBlob
+	dataColumn *RODataColumn
+}
+
+var (
+	errBlobNeeded       = errors.New("blob sidecar needed")
+	errDataColumnNeeded = errors.New("data column sidecar needed")
+)
+
+// NewSidecarFromBlobSidecar creates a new read-only (generic) sidecar from a read-only blob sidecar.
+func NewSidecarFromBlobSidecar(blob ROBlob) ROSidecar {
+	return ROSidecar{blob: &blob}
+}
+
+// NewSidecarFromDataColumnSidecar creates a new read-only (generic) sidecar from a read-only data column sidecar.
+func NewSidecarFromDataColumnSidecar(dataColumn RODataColumn) ROSidecar {
+	return ROSidecar{dataColumn: &dataColumn}
+}
+
+// NewSidecarsFromBlobSidecars creates a new slice of read-only (generic) sidecars from a slice of read-only blobs sidecars.
+func NewSidecarsFromBlobSidecars(blobSidecars []ROBlob) []ROSidecar {
+	sidecars := make([]ROSidecar, 0, len(blobSidecars))
+	for _, blob := range blobSidecars {
+		blobSidecar := ROSidecar{blob: &blob} // #nosec G601
+		sidecars = append(sidecars, blobSidecar)
+	}
+
+	return sidecars
+}
+
+// NewSidecarsFromDataColumnSidecars creates a new slice of read-only (generic) sidecars from a slice of read-only data column sidecars.
+func NewSidecarsFromDataColumnSidecars(dataColumnSidecars []RODataColumn) []ROSidecar {
+	sidecars := make([]ROSidecar, 0, len(dataColumnSidecars))
+	for _, dataColumn := range dataColumnSidecars {
+		dataColumnSidecar := ROSidecar{dataColumn: &dataColumn} // #nosec G601
+		sidecars = append(sidecars, dataColumnSidecar)
+	}
+
+	return sidecars
+}
+
+// Blob returns the blob sidecar.
+func (sc *ROSidecar) Blob() (ROBlob, error) {
+	if sc.blob == nil {
+		return ROBlob{}, errBlobNeeded
+	}
+
+	return *sc.blob, nil
+}
+
+// DataColumn returns the data column sidecar.
+func (sc *ROSidecar) DataColumn() (RODataColumn, error) {
+	if sc.dataColumn == nil {
+		return RODataColumn{}, errDataColumnNeeded
+	}
+
+	return *sc.dataColumn, nil
+}
+
+// BlobSidecarsFromSidecars creates a new slice of read-only blobs sidecars from a slice of read-only (generic) sidecars.
+func BlobSidecarsFromSidecars(sidecars []ROSidecar) ([]ROBlob, error) {
+	blobSidecars := make([]ROBlob, 0, len(sidecars))
+	for _, sidecar := range sidecars {
+		blob, err := sidecar.Blob()
+		if err != nil {
+			return nil, errors.Wrap(err, "blob")
+		}
+
+		blobSidecars = append(blobSidecars, blob)
+	}
+
+	return blobSidecars, nil
+}
+
+// DataColumnSidecarsFromSidecars creates a new slice of read-only data column sidecars from a slice of read-only (generic) sidecars.
+func DataColumnSidecarsFromSidecars(sidecars []ROSidecar) ([]RODataColumn, error) {
+	dataColumnSidecars := make([]RODataColumn, 0, len(sidecars))
+	for _, sidecar := range sidecars {
+		dataColumn, err := sidecar.DataColumn()
+		if err != nil {
+			return nil, errors.Wrap(err, "data column")
+		}
+
+		dataColumnSidecars = append(dataColumnSidecars, dataColumn)
+	}
+
+	return dataColumnSidecars, nil
+}

consensus-types/blocks/rosidecar_test.go

@@ -0,0 +1,109 @@
+package blocks
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewSidecarFromBlobSidecar(t *testing.T) {
+	blob := ROBlob{}
+	sidecar := NewSidecarFromBlobSidecar(blob)
+
+	// Check that the blob is set
+	retrievedBlob, err := sidecar.Blob()
+	require.NoError(t, err)
+	require.Equal(t, blob, retrievedBlob)
+
+	// Check that data column is not set
+	_, err = sidecar.DataColumn()
+	require.ErrorIs(t, err, errDataColumnNeeded)
+}
+
+func TestNewSidecarFromDataColumnSidecar(t *testing.T) {
+	dataColumn := RODataColumn{}
+	sidecar := NewSidecarFromDataColumnSidecar(dataColumn)
+
+	// Check that the data column is set
+	retrievedDataColumn, err := sidecar.DataColumn()
+	require.NoError(t, err)
+	require.Equal(t, dataColumn, retrievedDataColumn)
+
+	// Check that blob is not set
+	_, err = sidecar.Blob()
+	require.ErrorIs(t, err, errBlobNeeded)
+}
+
+func TestNewSidecarsFromBlobSidecars(t *testing.T) {
+	blobSidecars := []ROBlob{{}, {}}
+	sidecars := NewSidecarsFromBlobSidecars(blobSidecars)
+
+	require.Equal(t, len(blobSidecars), len(sidecars))
+
+	for i, sidecar := range sidecars {
+		retrievedBlob, err := sidecar.Blob()
+		require.NoError(t, err)
+		require.Equal(t, blobSidecars[i], retrievedBlob)
+	}
+}
+
+func TestNewSidecarsFromDataColumnSidecars(t *testing.T) {
+	dataColumnSidecars := []RODataColumn{{}, {}}
+	sidecars := NewSidecarsFromDataColumnSidecars(dataColumnSidecars)
+
+	require.Equal(t, len(dataColumnSidecars), len(sidecars))
+
+	for i, sidecar := range sidecars {
+		retrievedDataColumn, err := sidecar.DataColumn()
+		require.NoError(t, err)
+		require.Equal(t, dataColumnSidecars[i], retrievedDataColumn)
+	}
+}
+
+func TestBlobSidecarsFromSidecars(t *testing.T) {
+	// Create sidecars with blobs
+	blobSidecars := []ROBlob{{}, {}}
+	sidecars := NewSidecarsFromBlobSidecars(blobSidecars)
+
+	// Convert back to blob sidecars
+	retrievedBlobSidecars, err := BlobSidecarsFromSidecars(sidecars)
+	require.NoError(t, err)
+	require.Equal(t, len(blobSidecars), len(retrievedBlobSidecars))
+
+	for i, blob := range retrievedBlobSidecars {
+		require.Equal(t, blobSidecars[i], blob)
+	}
+
+	// Test with a mix of sidecar types
+	mixedSidecars := []ROSidecar{
+		NewSidecarFromBlobSidecar(ROBlob{}),
+		NewSidecarFromDataColumnSidecar(RODataColumn{}),
+	}
+
+	_, err = BlobSidecarsFromSidecars(mixedSidecars)
+	require.Error(t, err)
+}
+
+func TestDataColumnSidecarsFromSidecars(t *testing.T) {
+	// Create sidecars with data columns
+	dataColumnSidecars := []RODataColumn{{}, {}}
+	sidecars := NewSidecarsFromDataColumnSidecars(dataColumnSidecars)
+
+	// Convert back to data column sidecars
+	retrievedDataColumnSidecars, err := DataColumnSidecarsFromSidecars(sidecars)
+	require.NoError(t, err)
+	require.Equal(t, len(dataColumnSidecars), len(retrievedDataColumnSidecars))
+
+	for i, dataColumn := range retrievedDataColumnSidecars {
+		require.Equal(t, dataColumnSidecars[i], dataColumn)
+	}
+
+	// Test with a mix of sidecar types
+	mixedSidecars := []ROSidecar{
+		NewSidecarFromDataColumnSidecar(RODataColumn{}),
+		NewSidecarFromBlobSidecar(ROBlob{}),
+	}
+
+	_, err = DataColumnSidecarsFromSidecars(mixedSidecars)
+	require.Error(t, err)
+}