linera-io/linera-protocol · error

Failed to find port for {s}. {parse_error}

Error message

Failed to find port for {s}. {parse_error}

What it means

While parsing the 'tcp' segment of a scylladb storage URL, from_str expects two tokens after 'tcp': the hostname and then the port. This error means the hostname was consumed but the port token is missing — the string ends after 'tcp:hostname'.

Source

Thrown at linera-storage-runtime/src/storage_config.rs:191

                });
            }
            bail!("We should have one, two or three parts");
        }
        #[cfg(feature = "scylladb")]
        if let Some(s) = input.strip_prefix(SCYLLA_DB) {
            let mut uri: Option<String> = None;
            let mut namespace: Option<String> = None;
            let parse_error: &'static str = "Correct format is tcp:db_hostname:port.";
            if !s.is_empty() {
                let mut parts = s.split(':');
                while let Some(part) = parts.next() {
                    match part {
                        "tcp" => {
                            let address = parts.next().ok_or_else(|| {
                                anyhow!("Failed to find address for {s}. {parse_error}")
                            })?;
                            let port_str = parts.next().ok_or_else(|| {
                                anyhow!("Failed to find port for {s}. {parse_error}")
                            })?;
                            let port = NonZeroU16::from_str(port_str).map_err(|_| {
                                anyhow!(
                                    "Failed to find parse port {port_str} for {s}. {parse_error}",
                                )
                            })?;
                            if uri.is_some() {
                                bail!("The uri has already been assigned");
                            }
                            uri = Some(format!("{address}:{port}"));
                        }
                        _ if part.starts_with("table") => {
                            if namespace.is_some() {
                                bail!("The namespace has already been assigned");
                            }
                            namespace = Some(part.to_string());
                        }
                        _ => {

View on GitHub (pinned to 6c226ddcb3)

Solutions

  1. Add an explicit nonzero port: --storage scylladb:tcp:db.example.com:9042
  2. Or remove the incomplete tcp segment and rely on the localhost:9042 default

Example fix

# before
--storage scylladb:tcp:db.example.com
# after
--storage scylladb:tcp:db.example.com:9042
Defensive patterns

Strategy: validation

Validate before calling

// Rust: ensure every tcp segment has host AND port
fn tcp_segments_complete(s: &str) -> bool {
    let mut parts = s.split(':');
    while let Some(part) = parts.next() {
        if part == "tcp" {
            if parts.next().unwrap_or("").is_empty() { return false; }
            if parts.next().unwrap_or("").is_empty() { return false; }
        }
    }
    true
}

Type guard

fn has_complete_tcp_endpoint(s: &str) -> bool { tcp_segments_complete(s) }

Try / catch

if let Err(e) = StorageConfig::from_str(&storage) {
    eprintln!("storage config rejected: {e:#}; expected scylladb:tcp:host:port");
    std::process::exit(2);
}

Prevention

When it happens

Trigger: Passing --storage 'scylladb:tcp:db.example.com' without a port. Every tcp segment must be 'tcp:hostname:port', e.g. 'scylladb:tcp:db.example.com:9042'.

Common situations: Assuming a default port is implied (it is not — omit the whole tcp segment instead to get localhost:9042); URLs edited by hand or truncated in scripts.

Related errors


AI-assisted analysis of linera-io/linera-protocol@6c226ddcb3 (2026-08-22). Data as JSON: /api/errors/a88cd10772f3e142. Report an issue: GitHub.