Draft payload dispersal

Signed-off-by: litt3 <[email protected]>

api/clients/codecs/blob_codec.go

@@ -46,3 +46,26 @@ func GenericDecodeBlob(data []byte) ([]byte, error) {
 
 	return data, nil
 }
+
+// CreateCodec creates a new BlobCodec based on the defined polynomial form of payloads, and the desired
+// BlobEncodingVersion
+func CreateCodec(payloadPolynomialForm PolynomialForm, version BlobEncodingVersion) (BlobCodec, error) {
+	lowLevelCodec, err := BlobEncodingVersionToCodec(version)
+	if err != nil {
+		return nil, fmt.Errorf("create low level codec: %w", err)
+	}
+
+	switch payloadPolynomialForm {
+	case PolynomialFormCoeff:
+		// Data must NOT be IFFTed during blob construction, since the payload is already in PolynomialFormCoeff after
+		// being encoded.
+		return NewNoIFFTCodec(lowLevelCodec), nil
+	case PolynomialFormEval:
+		// Data MUST be IFFTed during blob construction, since the payload is in PolynomialFormEval after being encoded,
+		// but must be in PolynomialFormCoeff to produce a valid blob.
+		return NewIFFTCodec(lowLevelCodec), nil
+	default:
+		return nil, fmt.Errorf("unsupported polynomial form: %d", payloadPolynomialForm)
+	}
+
+}

api/clients/v2/payload_client_config.go

@@ -0,0 +1,43 @@
+package clients
+
+import (
+	"time"
+
+	"github.com/Layr-Labs/eigenda/api/clients/codecs"
+	"github.com/Layr-Labs/eigenda/core"
+	v2 "github.com/Layr-Labs/eigenda/core/v2"
+)
+
+// PayloadClientConfig contains configuration values that are needed by both PayloadRetriever and PayloadDisperser
+type PayloadClientConfig struct {
+	// The blob encoding version to use when writing and reading blobs
+	BlobEncodingVersion codecs.BlobEncodingVersion
+
+	// The Ethereum RPC URL to use for querying the Ethereum blockchain.
+	EthRpcUrl string
+
+	// The address of the EigenDABlobVerifier contract
+	EigenDABlobVerifierAddr string
+
+	// PayloadPolynomialForm is the initial form of a Payload after being encoded. The configured form does not imply
+	// any restrictions on the contents of a payload: it merely dictates how payload data is treated after being
+	// encoded.
+	//
+	// Since blobs sent to the disperser must be in coefficient form, the initial form of the encoded payload dictates
+	// what data processing must be performed during blob construction.
+	//
+	// The chosen form also dictates how the KZG commitment made to the blob can be used. If the encoded payload starts
+	// in PolynomialFormEval (meaning the data WILL be IFFTed before computing the commitment) then it will be possible
+	// to open points on the KZG commitment to prove that the field elements correspond to the commitment. If the
+	// encoded payload starts in PolynomialFormCoeff (meaning the data will NOT be IFFTed before computing the
+	// commitment) then it will not be possible to create a commitment opening: the blob will need to be supplied in its
+	// entirety to perform a verification that any part of the data matches the KZG commitment.
+	PayloadPolynomialForm codecs.PolynomialForm
+
+	// The timeout duration for contract calls
+	ContractCallTimeout time.Duration
+
+	BlobVersion v2.BlobVersion
+
+	Quorums []core.QuorumID
+}

api/clients/v2/payload_disperser.go

@@ -0,0 +1,227 @@
+package clients
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/Layr-Labs/eigenda/api/clients/codecs"
+	"github.com/Layr-Labs/eigenda/api/clients/v2/verification"
+	dispgrpc "github.com/Layr-Labs/eigenda/api/grpc/disperser/v2"
+	"github.com/Layr-Labs/eigenda/common/geth"
+	core "github.com/Layr-Labs/eigenda/core/v2"
+	"github.com/Layr-Labs/eigenda/encoding"
+	"github.com/Layr-Labs/eigensdk-go/logging"
+	gethcommon "github.com/ethereum/go-ethereum/common"
+)
+
+// PayloadDisperser provides the ability to disperse payloads to EigenDA
+//
+// This struct is goroutine safe.
+type PayloadDisperser struct {
+	log             logging.Logger
+	config          *PayloadDisperserConfig
+	codec           codecs.BlobCodec
+	disperserClient DisperserClient
+	blobVerifier    verification.IBlobVerifier
+}
+
+// BuildPayloadDisperser builds a PayloadDisperser from config structs
+func BuildPayloadDisperser(
+	log logging.Logger,
+	payloadDisperserConfig *PayloadDisperserConfig,
+	disperserClientConfig *DisperserClientConfig,
+// signer to sign blob dispersal requests
+	signer core.BlobRequestSigner,
+// prover is used to compute commitments to a new blob during the dispersal process
+//
+// IMPORTANT: it is permissible for the prover parameter to be nil, but operating with this configuration
+// puts a trust assumption on the disperser. With a nil prover, the disperser is responsible for computing
+// the commitments to a blob, and the PayloadDisperser doesn't have a mechanism to verify these commitments.
+//
+// TODO: In the future, an optimized method of commitment verification using fiat shamir transformation will
+//  be implemented. This feature will allow a PayloadDisperser to offload commitment generation onto the
+//  disperser, but the disperser's commitments will be verifiable without needing a full-fledged prover
+	prover encoding.Prover,
+	accountant *Accountant,
+	ethConfig geth.EthClientConfig,
+) (*PayloadDisperser, error) {
+
+	codec, err := codecs.CreateCodec(
+		payloadDisperserConfig.PayloadPolynomialForm,
+		payloadDisperserConfig.BlobEncodingVersion)
+	if err != nil {
+		return nil, fmt.Errorf("create codec: %w", err)
+	}
+
+	disperserClient, err := NewDisperserClient(disperserClientConfig, signer, prover, accountant)
+	if err != nil {
+		return nil, fmt.Errorf("unable to create disperser client: %s", err)
+	}
+
+	ethClient, err := geth.NewClient(ethConfig, gethcommon.Address{}, 0, log)
+	if err != nil {
+		return nil, fmt.Errorf("new eth client: %w", err)
+	}
+
+	blobVerifier, err := verification.NewBlobVerifier(*ethClient, payloadDisperserConfig.EigenDABlobVerifierAddr)
+	if err != nil {
+		return nil, fmt.Errorf("new blob verifier: %w", err)
+	}
+
+	return &PayloadDisperser{
+		log:             log,
+		config:          payloadDisperserConfig,
+		codec:           codec,
+		disperserClient: disperserClient,
+		blobVerifier:    blobVerifier,
+	}, nil
+}
+
+// SendPayload executes the dispersal of a payload, with these basic steps:
+//
+//  1. Encode payload into a blob
+//  2. Disperse the blob
+//  3. Continually poll the disperser with GetBlobStatus, until a terminal status is reached, or the polling timeout
+//     is reached
+//  4. Construct an EigenDACert if dispersal is successful
+//  5. Verify the constructed cert with a call to an ethereum contract
+//  6. Return the valid cert
+func (pd *PayloadDisperser) SendPayload(
+	ctx context.Context,
+	payload []byte,
+	salt uint32,
+) (*verification.EigenDACert, error) {
+
+	blobBytes, err := pd.codec.EncodeBlob(payload)
+	if err != nil {
+		return nil, fmt.Errorf("encode payload to blob: %w", err)
+	}
+
+	timeoutCtx, cancel := context.WithTimeout(ctx, pd.config.DisperseBlobTimeout)
+	defer cancel()
+	blobStatus, blobKey, err := pd.disperserClient.DisperseBlob(
+		timeoutCtx,
+		blobBytes,
+		pd.config.BlobVersion,
+		pd.config.Quorums,
+		salt)
+
+	if err != nil {
+		return nil, fmt.Errorf("disperse blob: %w", err)
+	}
+
+	timeoutCtx, cancel = context.WithTimeout(ctx, pd.config.BlobCertifiedTimeout)
+	defer cancel()
+
+	blobStatusReply, err := pd.pollBlobStatus(timeoutCtx, blobKey, blobStatus.ToProfobuf())
+	if err != nil {
+		return nil, fmt.Errorf("poll blob status: %w", err)
+	}
+
+	timeoutCtx, cancel = context.WithTimeout(ctx, pd.config.ContractCallTimeout)
+	defer cancel()
+	nonSignerStakesAndSignature, err := pd.blobVerifier.GetNonSignerStakesAndSignature(
+		timeoutCtx, blobStatusReply.GetSignedBatch())
+	if err != nil {
+		return nil, fmt.Errorf("get non signer stake and signature: %w", err)
+	}
+
+	eigenDACert, err := verification.BuildEigenDACert(
+		blobStatusReply.GetBlobInclusionInfo(),
+		blobStatusReply.GetSignedBatch().GetHeader(),
+		nonSignerStakesAndSignature)
+
+	if err != nil {
+		return nil, fmt.Errorf("build eigen da cert: %w", err)
+	}
+
+	err = pd.verifyCertWithTimeout(ctx, eigenDACert)
+	if err != nil {
+		return nil, fmt.Errorf("verify cert with timeout for blobKey %v: %w", blobKey, err)
+	}
+
+	return eigenDACert, nil
+}
+
+// Close is responsible for calling close on all internal clients. This method will do its best to close all internal
+// clients, even if some closes fail.
+//
+// Any and all errors returned from closing internal clients will be joined and returned.
+//
+// This method should only be called once.
+func (pd *PayloadDisperser) Close() error {
+	err := pd.disperserClient.Close()
+	if err != nil {
+		return fmt.Errorf("close disperser client: %w", err)
+	}
+
+	return nil
+}
+
+func (pd *PayloadDisperser) pollBlobStatus(
+	ctx context.Context,
+	blobKey core.BlobKey,
+	initialStatus dispgrpc.BlobStatus,
+) (*dispgrpc.BlobStatusReply, error) {
+
+	previousStatus := initialStatus
+
+	ticker := time.NewTicker(pd.config.BlobStatusPollInterval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, fmt.Errorf(
+				"timed out waiting for %v blob status, final status was %v: %w",
+				dispgrpc.BlobStatus_CERTIFIED,
+				previousStatus,
+				ctx.Err())
+		case <-ticker.C:
+			// This call to the disperser doesn't have a dedicated timeout configured.
+			// If this call fails to return in a timely fashion, the timeout configured for the poll loop will trigger
+			blobStatusReply, err := pd.disperserClient.GetBlobStatus(ctx, blobKey)
+
+			if err != nil {
+				pd.log.Warn("get blob status", "err", err, "blobKey", blobKey)
+				continue
+			}
+
+			newStatus := blobStatusReply.Status
+			if newStatus != previousStatus {
+				pd.log.Info(
+					"Blob status changed",
+					"blob key",
+					blobKey,
+					"previous status",
+					previousStatus,
+					"new status",
+					newStatus)
+				previousStatus = newStatus
+			}
+
+			switch newStatus {
+			case dispgrpc.BlobStatus_CERTIFIED:
+				return blobStatusReply, nil
+			case dispgrpc.BlobStatus_QUEUED, dispgrpc.BlobStatus_ENCODED:
+				continue
+			default:
+				return nil, fmt.Errorf("terminal dispersal failure for blobKey %v. blob status: %v", blobKey, newStatus)
+			}
+		}
+	}
+}
+
+// verifyCertWithTimeout verifies an EigenDACert by making a call to VerifyBlobV2.
+//
+// This method times out after the duration configured in PayloadDisperserConfig.ContractCallTimeout
+func (pd *PayloadDisperser) verifyCertWithTimeout(
+	ctx context.Context,
+	eigenDACert *verification.EigenDACert,
+) error {
+	timeoutCtx, cancel := context.WithTimeout(ctx, pd.config.ContractCallTimeout)
+	defer cancel()
+
+	return pd.blobVerifier.VerifyBlobV2(timeoutCtx, eigenDACert)
+}

api/clients/v2/payload_disperser_config.go

@@ -0,0 +1,21 @@
+package clients
+
+import "time"
+
+// PayloadDisperserConfig contains an embedded PayloadClientConfig, plus all additional configuration values needed
+// by a PayloadDisperser
+type PayloadDisperserConfig struct {
+	PayloadClientConfig
+
+	// DisperseBlobTimeout is the duration after which the PayloadDisperser will time out, when trying to disperse a
+	// blob
+	DisperseBlobTimeout time.Duration
+
+	// BlobCertifiedTimeout is the duration after which the PayloadDisperser will time out, while polling
+	// the disperser for blob status, waiting for BlobStatus_CERTIFIED
+	BlobCertifiedTimeout time.Duration
+
+	// BlobStatusPollInterval is the tick rate for the PayloadDisperser to use, while polling the disperser with
+	// GetBlobStatus.
+	BlobStatusPollInterval time.Duration
+}