spacedriveapp/spacedrive · error · anyhow::Error

Failed to read response length: {}

Error message

Failed to read response length: {}

What it means

Reading the 4-byte response length header failed inside the 60-second timeout window. The peer closed the stream without sending a response (clean EOF or stream reset), or the connection was lost before any response bytes arrived. The request reached a peer that did not answer.

Source

Thrown at core/src/service/network/transports/sync.rs:282

		send.write_all(&len.to_be_bytes())
			.await
			.map_err(|e| anyhow::anyhow!("Failed to send length: {}", e))?;
		send.write_all(&req_bytes)
			.await
			.map_err(|e| anyhow::anyhow!("Failed to send request: {}", e))?;

		// Properly close send stream
		send.finish()
			.map_err(|e| anyhow::anyhow!("Failed to finish stream: {}", e))?;

		debug!("Sync request sent, waiting for response...");

		// Read response with timeout
		let result = timeout(Duration::from_secs(60), async {
			let mut len_buf = [0u8; 4];
			recv.read_exact(&mut len_buf)
				.await
				.map_err(|e| anyhow::anyhow!("Failed to read response length: {}", e))?;
			let resp_len = u32::from_be_bytes(len_buf) as usize;

			debug!("Receiving sync response of {} bytes", resp_len);

			let mut resp_buf = vec![0u8; resp_len];
			recv.read_exact(&mut resp_buf)
				.await
				.map_err(|e| anyhow::anyhow!("Failed to read response: {}", e))?;
			Ok::<_, anyhow::Error>(resp_buf)
		})
		.await;

		let resp_buf = match result {
			Ok(Ok(buf)) => buf,
			Ok(Err(e)) => return Err(e),
			Err(_) => {
				return Err(anyhow::anyhow!(
					"Sync request timed out after 60s - peer {} not responding",

View on GitHub (pinned to 6dfeccf211)

Solutions

1. Check the peer's logs for a handler error or panic corresponding to the request
2. Verify both peers run compatible sync protocol versions and update them to match
3. Retry once; if the peer consistently closes without responding, mark it unavailable for this session

match recv.read_exact(&mut len_buf).await {
    Err(_) => {
        // peer closed without responding: mark partner suspect, retry once, then back off
    }
    Ok(_) => { /* continue */ }
}

When it happens

Trigger: Peer accepted the stream but its sync handler errored and closed; peer process crashed mid-exchange; version skew where the peer does not implement the length-prefixed response protocol for this message type.

Common situations: Mixed versions during rollout; peers under load rejecting streams; handler panics on unexpected message variants.

Related errors

• Failed to read response length: {}
• Failed to read response: {}
• Failed to read response: {}
• Failed to open bidirectional stream: {}
• Failed to send length: {}

AI-assisted analysis of spacedriveapp/spacedrive@6dfeccf211 (2026-08-16). Data as JSON: /api/errors/5b2b2748a175583d. Report an issue: GitHub.