nautechsystems/nautilus_trader · error

Blockchain address '{address}' is incorrect: {e}

Error message

Blockchain address '{address}' is incorrect: {e}

What it means

validate_address parses an Ethereum address string into an alloy Address after checking the 0x prefix. This error wraps the low-level parse failure: the string has invalid length (must be 42 chars including 0x) or contains non-hexadecimal characters. The library throws it to surface malformed blockchain identifiers early instead of propagating them into pool or token state.

Source

Thrown at crates/model/src/defi/validation.rs:43

/// Validates an Ethereum address format, checksum, and returns the parsed address.
///
/// # Errors
///
/// This function returns an error if:
/// - The address does not start with the `0x` prefix.
/// - The address has invalid length (must be 42 characters including `0x`).
/// - The address contains invalid hexadecimal characters.
/// - The address has an incorrect checksum (for checksummed addresses).
pub fn validate_address(address: &str) -> anyhow::Result<Address> {
    // Check if the address starts with "0x"
    if !address.starts_with("0x") {
        anyhow::bail!("Ethereum address must start with '0x': {address}");
    }

    // Check if the address is valid
    let parsed_address = Address::from_str(address)
        .map_err(|e| anyhow::anyhow!("Blockchain address '{address}' is incorrect: {e}"))?;

    // Check if checksum is valid
    Address::parse_checksummed(address, None)
        .map_err(|_| anyhow::anyhow!("Blockchain address '{address}' has incorrect checksum"))?;

    Ok(parsed_address)
}

#[cfg(test)]
mod tests {
    use rstest::rstest;

    use super::*;

    #[rstest]
    fn test_validate_address_invalid_prefix() {
        let invalid_address = "742d35Cc6634C0532925a3b844Bc454e4438f44e";
        let result = validate_address(invalid_address);

View on GitHub (pinned to 18893faf8b)

Solutions

1. Ensure the address string is exactly 42 characters and starts with 0x.
2. Strip surrounding whitespace/quotes and trim before validating.
3. Verify the address source (config file, CSV, database) for truncation or encoding issues.
4. Regenerate the address from a trusted source; a parse failure usually means a typo.

Example fix

// before
let addr = validate_address(raw_address.trim_matches('"'))?;
// after
let cleaned = raw_address.trim().trim_start_matches("\"").trim_end_matches("\"").to_lowercase();
if cleaned.len() != 42 || !cleaned.starts_with("0x") {
    anyhow::bail!("malformed address: {raw_address}");
}
let addr = validate_address(&cleaned)?;

fn looks_like_eth_address(s: &str) -> bool {
    let s = s.trim();
    s.len() == 42 && s.starts_with("0x") && s[2..].chars().all(|c| c.is_ascii_hexdigit())
}

fn parse_eth_address(s: &str) -> Option<alloy_primitives::Address> {
    alloy_primitives::Address::from_str(s.trim()).ok()
}

match validate_address(input.trim()) {
    Ok(addr) => addr,
    Err(e) if e.to_string().contains("is incorrect") => {
        tracing::warn!("malformed address in config: {input}");
        return Err(e);
    }
    Err(e) => return Err(e),
}

When it happens

Trigger: Calling validate_address (or APIs that call it: PoolPosition construction, decode_address, multicall setup, subscribe handling) with a string that is not exactly '0x' + 40 hex characters, or contains invalid characters.

Common situations: Hardcoded addresses with typos; addresses truncated or pasted without the 0x prefix handled elsewhere; reading token addresses from a config/CSV with whitespace or quotes; mixing 20-byte binary data rendered as decimal.

Understand the failure class

Background: "invalid id" errors: invalid identifier format — why libraries reject IDs before lookup, and how to fix them — this error's family across 37 libraries.

Related errors

• Ethereum address must start with '0x': {address}
• Deployment manifest address is invalid
• Deployment manifest must contain exactly one {description} c
• Deployment manifest token address is invalid
• Deployment manifest has no wrapped native token identity

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/f611df9c0cd131fd. Report an issue: GitHub.