allow users to publish blobs (#14442)

* allow users to publish blobs

Allowing users to publish blobs before publishing blocks, gives the blobs a head start. They can begin to propagate around the network while the block is being validated.

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

* Update beacon-chain/rpc/prysm/beacon/handlers.go

---------

Co-authored-by: Radosław Kapka <radoslaw.kapka@gmail.com>

api/server/structs/BUILD.bazel

@@ -5,6 +5,7 @@ go_library(
     srcs = [
         "block.go",
         "conversions.go",
+        "conversions_blob.go",
         "conversions_block.go",
         "conversions_lightclient.go",
         "conversions_state.go",

api/server/structs/conversions_blob.go

@@ -0,0 +1,61 @@
+package structs
+
+import (
+	"strconv"
+
+	"github.com/prysmaticlabs/prysm/v5/api/server"
+	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
+	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
+)
+
+func (sc *Sidecar) ToConsensus() (*eth.BlobSidecar, error) {
+	if sc == nil {
+		return nil, errNilValue
+	}
+
+	index, err := strconv.ParseUint(sc.Index, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Index")
+	}
+
+	blob, err := bytesutil.DecodeHexWithLength(sc.Blob, 131072)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Blob")
+	}
+
+	kzgCommitment, err := bytesutil.DecodeHexWithLength(sc.KzgCommitment, 48)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "KzgCommitment")
+	}
+
+	kzgProof, err := bytesutil.DecodeHexWithLength(sc.KzgProof, 48)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "KzgProof")
+	}
+
+	header, err := sc.SignedBeaconBlockHeader.ToConsensus()
+	if err != nil {
+		return nil, server.NewDecodeError(err, "SignedBeaconBlockHeader")
+	}
+
+	// decode the commitment inclusion proof
+	var commitmentInclusionProof [][]byte
+	for _, proof := range sc.CommitmentInclusionProof {
+		proofBytes, err := bytesutil.DecodeHexWithLength(proof, 32)
+		if err != nil {
+			return nil, server.NewDecodeError(err, "CommitmentInclusionProof")
+		}
+		commitmentInclusionProof = append(commitmentInclusionProof, proofBytes)
+	}
+
+	bsc := &eth.BlobSidecar{
+		Index:                    index,
+		Blob:                     blob,
+		KzgCommitment:            kzgCommitment,
+		KzgProof:                 kzgProof,
+		SignedBlockHeader:        header,
+		CommitmentInclusionProof: commitmentInclusionProof,
+	}
+
+	return bsc, nil
+}

api/server/structs/conversions_block.go

@@ -20,6 +20,9 @@ import (
 var ErrUnsupportedConversion = errors.New("Could not determine api struct type to use for value")
 
 func (h *SignedBeaconBlockHeader) ToConsensus() (*eth.SignedBeaconBlockHeader, error) {
+	if h == nil {
+		return nil, errNilValue
+	}
 	msg, err := h.Message.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Message")
@@ -36,6 +39,9 @@ func (h *SignedBeaconBlockHeader) ToConsensus() (*eth.SignedBeaconBlockHeader, e
 }
 
 func (h *BeaconBlockHeader) ToConsensus() (*eth.BeaconBlockHeader, error) {
+	if h == nil {
+		return nil, errNilValue
+	}
 	s, err := strconv.ParseUint(h.Slot, 10, 64)
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Slot")

api/server/structs/endpoints_blob.go

@@ -12,3 +12,12 @@ type Sidecar struct {
 	KzgProof                 string                   `json:"kzg_proof"`
 	CommitmentInclusionProof []string                 `json:"kzg_commitment_inclusion_proof"`
 }
+
+type BlobSidecars struct {
+	Sidecars []*Sidecar `json:"sidecars"`
+}
+
+type PublishBlobsRequest struct {
+	BlobSidecars *BlobSidecars `json:"blob_sidecars"`
+	BlockRoot    string        `json:"block_root"`
+}