Rust crate (bezant)

Full rustdoc is deployed alongside this book — see Rust API reference.

Feature tour

Typed client with sane defaults

use std::time::Duration;

#[tokio::main]
async fn main() -> bezant::Result<()> {
    let client = bezant::Client::builder("https://localhost:5000/v1/api")
        .timeout(Duration::from_secs(30))
        .accept_invalid_certs(true)       // Gateway uses a self-signed cert
        .user_agent("my-bot/0.1")
        .build()?;

    // keeps /tickle firing every 60s in the background
    let _keepalive = client.spawn_keepalive(Duration::from_secs(60));

    // returns typed errors: NotAuthenticated, NoSession, Http, Api, ...
    let status = client.health().await?;
    println!("gateway: {status:?}");
    Ok(())
}

Paginated positions helper

Skip writing the /positions/{page} loop yourself:

#![allow(unused)]
fn main() {
use bezant::Client;
async fn demo(client: Client) -> bezant::Result<()> {
let positions: Vec<bezant::Position> = client.all_positions("DU123456").await?;
println!("{} open positions", positions.len());
Ok(()) }
}

Symbol → conid cache

#![allow(unused)]
fn main() {
use bezant::Client;
async fn demo(client: Client) -> bezant::Result<()> {
let cache = bezant::SymbolCache::new(client);
let aapl = cache.conid_for("AAPL").await?;   // network call
let aapl2 = cache.conid_for("AAPL").await?;  // cached
assert_eq!(aapl, aapl2);
Ok(()) }
}

WebSocket streaming

#![allow(unused)]
fn main() {
use bezant::{Client, WsClient, MarketDataFields, WsMessage};
async fn demo(client: Client) -> bezant::Result<()> {
let mut ws = WsClient::connect(&client).await?;
ws.subscribe_market_data(265598 /* AAPL */, &MarketDataFields::default_l1()).await?;

while let Some(msg) = ws.next_message().await? {
    match msg {
        WsMessage::MarketData { conid, payload } => println!("{conid}: {payload}"),
        WsMessage::Order(o) => println!("order update: {o}"),
        _ => {}
    }
}
Ok(()) }
}

Raw access to every CPAPI endpoint

The ergonomic facade covers the 80% use case. For the long tail (155 endpoints) drop straight into the generated client:

#![allow(unused)]
fn main() {
use bezant::Client;
async fn demo(client: Client) -> bezant::Result<()> {
let resp = client
    .api()
    .get_portfolio_summary(bezant::api::GetPortfolioSummaryRequest {
        path: bezant::api::GetPortfolioSummaryRequestPath {
            account_id: "DU123456".into(),
        },
    })
    .await?;
Ok(()) }
}

Error handling

bezant::Error is #[non_exhaustive] and covers:

Client code should pattern-match on the variants it cares about and use _ => ... for the rest (important because the enum is #[non_exhaustive]).

Runnable examples

Clone the repo and try the bundled examples against the local Docker gateway without writing any code:

docker compose up -d
# open https://localhost:5000 once in your browser to log in

cargo run -p bezant-core --example health
IBKR_ACCOUNT_ID=DU123456 cargo run -p bezant-core --example list_positions
IBKR_SYMBOL=AAPL        cargo run -p bezant-core --example stream_quotes

Source: crates/bezant-core/examples/.