nautechsystems/nautilus_trader · info

non-zero

Error message

non-zero

What it means

COINBASE_WS_CONNECTION_QUOTA builds a governor Quota of 8 connections per second, asserting via NonZeroU32::new(8).expect("non-zero") that the rate is valid. The panic is a constant sanity check: Quota::per_second rejects zero, but 8 is a hard-coded non-zero literal, so this can never fire as shipped.

Source

Thrown at crates/adapters/coinbase/src/websocket/client.rs:71

use crate::{
    common::{
        consts::{
            RECONNECT_BACKOFF_FACTOR, RECONNECT_BASE_BACKOFF, RECONNECT_JITTER_MS,
            RECONNECT_MAX_BACKOFF, RECONNECT_TIMEOUT, WS_DISCONNECT_TIMEOUT, WS_HEARTBEAT_SECS,
        },
        credential::CoinbaseCredential,
        enums::CoinbaseWsChannel,
    },
    websocket::{
        handler::{FeedHandler, HandlerCommand, NautilusWsMessage},
        messages::{CoinbaseWsAction, CoinbaseWsSubscription},
    },
};

/// Coinbase WebSocket connection rate limit (8 per second per IP).
pub static COINBASE_WS_CONNECTION_QUOTA: LazyLock<Quota> = LazyLock::new(|| {
    Quota::per_second(NonZeroU32::new(8).expect("non-zero")).expect("valid constant")
});

/// Coinbase WebSocket subscribe/unsubscribe rate limit (8 per second per IP).
pub static COINBASE_WS_SUBSCRIPTION_QUOTA: LazyLock<Quota> = LazyLock::new(|| {
    Quota::per_second(NonZeroU32::new(8).expect("non-zero")).expect("valid constant")
});

/// Rate-limit key for subscribe/unsubscribe operations.
pub const COINBASE_RATE_LIMIT_KEY_SUBSCRIPTION: &str = "subscription";

/// Pre-interned [`COINBASE_RATE_LIMIT_KEY_SUBSCRIPTION`] slice.
pub static COINBASE_WS_SUBSCRIPTION_KEYS: LazyLock<[Ustr; 1]> =
    LazyLock::new(|| [Ustr::from(COINBASE_RATE_LIMIT_KEY_SUBSCRIPTION)]);

/// WebSocket client for Coinbase Advanced Trade market data and user streams.
///
/// Manages connection lifecycle, subscription state, and JWT authentication.
/// Spawns a [`FeedHandler`] task that parses raw messages into Nautilus types.

View on GitHub (pinned to 18893faf8b)

Solutions

1. Keep the rate constant non-zero; disable connections at a higher level instead of a zero quota.
2. Consider NonZeroU32 constants declared with core::num::NonZeroU32::new(8).unwrap() in a const context to fail earlier.

Example fix

// before
Quota::per_second(NonZeroU32::new(0).expect("non-zero")) // panics at init
// after
Quota::per_second(NonZeroU32::new(8).expect("non-zero"))

// Library-internal constant check; users cannot trigger it. Maintainers:
const WS_CONNECT_RPS: u32 = 8;
assert!(WS_CONNECT_RPS > 0);

When it happens

Trigger: Only if the literal 8 were edited to 0 and the static were first initialized.

Common situations: A developer tuning the WebSocket connect rate limit and setting it to 0 (intending to disable connections) triggers this panic on first use of the quota.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

• non-zero
• InstrumentState channel requires kind and currency parameter
• Coinbase WebSocket handler failed: {error}
• Coinbase WebSocket handler did not stop after abort
• Failed to send SetClient command: {e}

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/6c836041f60b1de7. Report an issue: GitHub.