hyperledger/fabric · error

error unmarshalling ChaicnodeEvent

Error message

error unmarshalling ChaicnodeEvent

What it means

Returned by protoutil.UnmarshalChaincodeEvents when proto.Unmarshal fails to decode bytes into a peer.ChaincodeEvent. Note the wrapped message text contains a typo ("ChaicnodeEvent") in this library version. It indicates the event bytes are empty, truncated, or not an encoded ChaincodeEvent.

Source

Thrown at protoutil/unmarshalers.go:137

// UnmarshalChaincodeAction unmarshals bytes to a ChaincodeAction
func UnmarshalChaincodeAction(caBytes []byte) (*peer.ChaincodeAction, error) {
	chaincodeAction := &peer.ChaincodeAction{}
	err := proto.Unmarshal(caBytes, chaincodeAction)
	return chaincodeAction, errors.Wrap(err, "error unmarshalling ChaincodeAction")
}

// UnmarshalResponse unmarshals bytes to a Response
func UnmarshalResponse(resBytes []byte) (*peer.Response, error) {
	response := &peer.Response{}
	err := proto.Unmarshal(resBytes, response)
	return response, errors.Wrap(err, "error unmarshalling Response")
}

// UnmarshalChaincodeEvents unmarshals bytes to a ChaincodeEvent
func UnmarshalChaincodeEvents(eBytes []byte) (*peer.ChaincodeEvent, error) {
	chaincodeEvent := &peer.ChaincodeEvent{}
	err := proto.Unmarshal(eBytes, chaincodeEvent)
	return chaincodeEvent, errors.Wrap(err, "error unmarshalling ChaicnodeEvent")
}

// UnmarshalProposalResponsePayload unmarshals bytes to a ProposalResponsePayload
func UnmarshalProposalResponsePayload(prpBytes []byte) (*peer.ProposalResponsePayload, error) {
	prp := &peer.ProposalResponsePayload{}
	err := proto.Unmarshal(prpBytes, prp)
	return prp, errors.Wrap(err, "error unmarshalling ProposalResponsePayload")
}

// UnmarshalProposal unmarshals bytes to a Proposal
func UnmarshalProposal(propBytes []byte) (*peer.Proposal, error) {
	prop := &peer.Proposal{}
	err := proto.Unmarshal(propBytes, prop)
	return prop, errors.Wrap(err, "error unmarshalling Proposal")
}

// UnmarshalTransaction unmarshals bytes to a Transaction
func UnmarshalTransaction(txBytes []byte) (*peer.Transaction, error) {

View on GitHub (pinned to 2736b63f8f)

Solutions

1. Check for empty event bytes first — a nil event is normal when the chaincode emits none — before treating failure as an error.
2. Verify the bytes come from ChaincodeAction.Events, not another field.
3. Ensure chaincode SetEvent usage marshals plain bytes compatible with the peer's protobuf version.
4. Upgrade/align peer and consumer SDK versions so the ChaincodeEvent schema matches.
5. On failure, skip the transaction's event (log and continue) rather than aborting block processing.

Example fix

// before
ev, _ := protoutil.UnmarshalChaincodeEvents(action.Events) // panics later on nil use
// after
if len(action.Events) == 0 {
    return nil // no event emitted
}
ev, err := protoutil.UnmarshalChaincodeEvents(action.Events)
if err != nil {
    return fmt.Errorf("bad chaincode event: %w", err)
}

func hasChaincodeEvent(action *peer.ChaincodeAction) bool {
    return action != nil && len(action.Events) > 0
}

func isChaincodeEvent(v any) bool {
    ev, ok := v.(*peer.ChaincodeEvent)
    return ok && ev.ChaincodeId != ""
}

if len(action.Events) == 0 {
    return nil // no event emitted, not an error
}
ev, err := protoutil.UnmarshalChaincodeEvents(action.Events)
if err != nil {
    log.Warnf("skipping bad chaincode event: %v", err)
    return nil
}

When it happens

Trigger: Calling UnmarshalChaincodeEvents on TxReadWriteSet/chaincode action event fields that are empty (chaincode emitted no event), corrupted, or of another message type; used in filtered block/event processing (toFilteredActions, eventDiff).

Common situations: Listening to block events where some transactions legitimately have no chaincode event; parsing events across differing Fabric versions; event payloads corrupted by custom serialization.

Understand the failure class

Background: "cannot parse invalid wire-format data", "cannot unmarshal", "failed unmarshalling": protobuf unmarshal errors explained — this error's family across 10 libraries.

Related errors

• error unmarshalling ChaincodeHeaderExtension
• error unmarshalling ChaincodeAction
• error unmarshalling Response
• error unmarshalling
• error unmarshalling original config

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/5396f94ceb135276. Report an issue: GitHub.