nautechsystems/nautilus_trader · critical

Redis config error: username supplied without password. Eith

Error message

Redis config error: username supplied without password. Either supply a password or omit the username.

What it means

`get_redis_url` in crates/infrastructure/src/redis/mod.rs validates the credential configuration and panics when a username is provided without a password. A Redis URL with credentials requires both parts (or neither); the partial combination would produce a malformed/ambiguous URL, so the function treats it as a hard configuration error. This is a user-facing config mistake surfaced as a panic at connection-setup time.

Source

Thrown at crates/infrastructure/src/redis/mod.rs:132

        } else {
            pw.to_owned()
        }
    };

    // Build the `userinfo@` portion for both the real and redacted URLs.
    let (auth, auth_redacted) = match (username.is_empty(), password.is_empty()) {
        // user:pass@
        (false, false) => (
            format!("{username}:{password}@"),
            format!("{username}:{}@", redact_pw(password)),
        ),
        // :pass@
        (true, false) => (
            format!(":{password}@"),
            format!(":{}@", redact_pw(password)),
        ),
        // username but no password ⇒  configuration error
        (false, true) => panic!(
            "Redis config error: username supplied without password. \
            Either supply a password or omit the username."
        ),
        // no credentials
        (true, true) => (String::new(), String::new()),
    };

    let scheme = if ssl { "rediss" } else { "redis" };

    let url = format!("{scheme}://{auth}{host}:{port}");
    let redacted_url = format!("{scheme}://{auth_redacted}{host}:{port}");

    (url, redacted_url)
}

/// Creates a new Redis connection manager based on the provided database `config` and connection name.
///
/// # Errors

View on GitHub (pinned to 18893faf8b)

Solutions

Supply the password alongside the username in the Redis config (check the relevant env var, e.g. REDIS_PASSWORD, is actually set).
Remove the username if the Redis instance does not use authentication (omit both).
Validate the config before startup: assert password.is_some() whenever username is set.

Example fix

// before
RedisConfig { username: Some("default".into()), password: None, .. } // panics

// after
RedisConfig { username: Some("default".into()), password: Some("secret".into()), .. }
// or username: None, password: None

Defensive patterns

Strategy: validation

Validate before calling

// before building the config
if config.username.is_some() && config.password.as_deref().map_or(true, str::is_empty) {
    return Err("password required when username is set");
}

Try / catch

// validate config at startup and fail fast with a clear message:
validate_redis_config(&cfg).expect("invalid Redis credentials: username requires password");

Prevention

Set both REDIS username and password env vars together, or neither.
Check env var spelling and container secret mounting when credentials look partial.
Run a config preflight check before the node connects to Redis.

When it happens

Trigger: Building a RedisConfig with `username` set but `password` None/empty, then calling `get_redis_url` (directly or via `create_redis_connection`). The match arm `(false, true)` (no password, username present) triggers the panic.

Common situations: Redis Cloud/MemoryDB setups where only a username is copied from the console; partially redacted configs where the password env var is unset but the username is set; mistyping the password env variable name.

Related errors

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/ac1e0fac3f263f6e. Report an issue: GitHub.