risingwavelabs/risingwave · error · anyhow::Error

None msg in request

Error message

None msg in request

What it means

The coordinator received a `CoordinateRequest` whose oneof `msg` field was unset (None). Protobuf oneof fields can be absent when a peer sends an empty/default message, and the coordinator cannot dispatch a message with no variant. This indicates a protocol violation by the sender.

Source

Thrown at src/meta/src/manager/sink_coordination/handle.rs:121

    }

    pub(super) fn stop(&mut self) -> anyhow::Result<()> {
        self.response_tx
            .send(Ok(CoordinateResponse {
                msg: Some(coordinate_response::Msg::Stopped(true)),
            }))
            .map_err(|_| anyhow!("failed to send the stopped response"))
    }

    pub(super) fn poll_next_request(
        &mut self,
        cx: &mut Context<'_>,
    ) -> Poll<anyhow::Result<coordinate_request::Msg>> {
        let result = try {
            let request = ready!(self.request_stream.try_poll_next_unpin(cx))
                .ok_or_else(|| anyhow!("end of request stream"))?
                .map_err(anyhow::Error::from)?;
            let request = request.msg.ok_or_else(|| anyhow!("None msg in request"))?;
            match &request {
                coordinate_request::Msg::StartRequest(_)
                | coordinate_request::Msg::Stop(_)
                | coordinate_request::Msg::AlignInitialEpochRequest(_) => {}
                coordinate_request::Msg::CommitRequest(request) => {
                    if let Some(prev_epoch) = self.prev_epoch
                        && request.epoch < prev_epoch
                    {
                        return Poll::Ready(Err(anyhow!(
                            "invalid commit epoch {}, prev_epoch {}",
                            request.epoch,
                            prev_epoch
                        )));
                    }
                    if request.metadata.is_none() {
                        return Poll::Ready(Err(anyhow!("empty commit metadata")));
                    };
                    self.prev_epoch = Some(request.epoch);

View on GitHub (pinned to 6469eb736d)

Solutions

1. Check that all sink executors and meta nodes run the same RisingWave version (protobuf definitions in sync).
2. Inspect the sender code path that builds `CoordinateRequest` and ensure it always sets `msg`.
3. Reproduce with debug logging on the coordinate stream to capture the raw message before dispatch.
4. If a protobuf schema change is in flight, regenerate `prost` types consistently on both sides.

Example fix

// before
CoordinateRequest { msg: None }
// after
CoordinateRequest { msg: Some(coordinate_request::Msg::StartRequest(Default::default())) }

// Sender side: always set msg before sending
let request = CoordinateRequest { msg: Some(msg) };
assert!(request.msg.is_some(), "CoordinateRequest must carry a msg");

match handle.poll_next_request(cx) {
    Poll::Ready(Err(e)) if e.to_string().contains("None msg in request") => {
        tracing::error!("peer sent empty CoordinateRequest; check version skew: {e:#}");
    }
    other => { /* normal handling */ }
}

When it happens

Trigger: A `CoordinateRequest` arrives over the request stream with all optional `msg` variants unset — e.g. the client constructed the message without setting `msg`, or a version mismatch drops the field during serialization.

Common situations: Mixed RisingWave versions (older executor sends a message shape the current meta does not expect); a client bug building `CoordinateRequest { msg: None }`; corrupted or truncated gRPC frames decoded as empty messages.

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

• empty vnode bitmap
• failed to send the commit response for epoch {}
• failed to send the stopped response
• end of request stream
• empty commit metadata

AI-assisted analysis of risingwavelabs/risingwave@6469eb736d (2026-09-11). Data as JSON: /api/errors/f5261fe2d47c5bbe. Report an issue: GitHub.