hyperledger/fabric · warning

failed to marshal args

Error message

failed to marshal args

What it means

createProposal() failed to proto-marshal the GetInstalledChaincodePackageArgs struct into bytes before building the chaincode input. This is nearly impossible in normal operation since the args contain a single string field, and indicates a serialization-layer failure.

Source

Thrown at internal/peer/lifecycle/chaincode/getinstalledpackage.go:181

	err = i.Writer.WriteFile(dir, name, result.ChaincodeInstallPackage)
	if err != nil {
		err = errors.Wrapf(err, "failed to write chaincode package to %s", outputFile)
		logger.Error(err.Error())
		return err
	}

	return nil
}

func (i *InstalledPackageGetter) createProposal() (*pb.Proposal, error) {
	args := &lb.GetInstalledChaincodePackageArgs{
		PackageId: i.Input.PackageID,
	}

	argsBytes, err := proto.Marshal(args)
	if err != nil {
		return nil, errors.Wrap(err, "failed to marshal args")
	}

	ccInput := &pb.ChaincodeInput{
		Args: [][]byte{[]byte("GetInstalledChaincodePackage"), argsBytes},
	}

	cis := &pb.ChaincodeInvocationSpec{
		ChaincodeSpec: &pb.ChaincodeSpec{
			ChaincodeId: &pb.ChaincodeID{Name: lifecycleName},
			Input:       ccInput,
		},
	}

	signerSerialized, err := i.Signer.Serialize()
	if err != nil {
		return nil, errors.WithMessage(err, "failed to serialize identity")
	}

View on GitHub (pinned to 2736b63f8f)

Solutions

1. Rebuild the peer CLI binary from matching Fabric sources/tag.
2. Ensure the binary uses the Fabric-vendored protobuf libraries (no dependency overrides).
3. Retry with an official Fabric release binary instead of a custom build.

Example fix

// before: custom build with replaced proto deps
go build -mod=mod ./cmd/peer
// after: use vendored Fabric deps
go build -mod=vendor ./cmd/peer

proposal, err := createProposal(...)
if err != nil && strings.Contains(err.Error(), "failed to marshal args") {
    // rebuild binary with correct Fabric deps and retry
}

When it happens

Trigger: proto.Marshal(args) returns an error while constructing the GetInstalledChaincodePackage proposal from i.Input.PackageID.

Common situations: Generated protobuf code/registry mismatch between the CLI binary and its vendored gogo/protobuf runtime; corrupted or stripped binary builds; practically never seen in normal usage.

Related errors

• could not marshal field %s
• proto: Marshal called with nil
• unsupported pointer type %v for field %s (must be proto)
• failed to marshal updated readiness result
• error marshaling proposal

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/85e52ca63f3ab9e5. Report an issue: GitHub.