#trading #kraken #exchange #websocket #api-calls

bin+lib krakenrs

Rust bindings to the Kraken REST API and websockets API for spot trading

16 stable releases (4 major)

5.2.3 Jan 24, 2022
5.2.2 Dec 24, 2021
4.1.0 Dec 19, 2021
3.0.0 Dec 19, 2021
1.0.1 Sep 20, 2021

#11 in #kraken

Download history 10/week @ 2024-07-15 37/week @ 2024-07-29 35/week @ 2024-09-23

54 downloads per month

WTFPL license

130KB
2.5K SLoC

krakenrs

Unofficial bindings to Kraken spot trading API in Rust.

This library provides a Rust client object implementing many of the calls from the Kraken REST API with an idiomatic Rust interface, including getting ticker info and making market and limit orders. Additionally it provides access to the Kraken WS API, both subscribing to feeds and submitting orders.

  • Requests and responses are strongly-typed, conversion done using serde_json
  • reqwest is used for https
  • tokio-tungstenite is used for websockets
  • RustCrypto crates used for the Kraken authentication scheme
  • rust_decimal used to represent Decimal values from kraken
  • log is used for logging
  • Robust error handling

Both public and private APIs are supported, but not all the calls and options are exposed, only the ones that were needed. If something you need is missing, patches are welcome! Just open a github issue or pull request.

Features

To get the websockets API, the "ws" feature must be enabled. It is on by default. Otherwise you only get the REST API, which can do all the same things (and more), but has more strict rate limits.

Threading

Unlike some other bindings, these are not async APIs (although the websockets feeds are implicitly asynchronous).

We have chosen to create blocking APIs for the Kraken REST API version for a few reasons:

  • simplicity
  • ease of debugging
  • when trying to make multiple private REST API calls in parallel, we often see invalid nonce errors this is because the nonces are based on timestamps, but when multiple requests are created and sent in parallel, this is inherently racy and sometimes the request with the higher nonce will be processed by kraken first, invalidating the others.

Additionally, the REST API has quite strict rate limits so making large numbers of requests in parallel isn't really possible.

Instead, it seems better to lean on the Websockets API, which is easy to use whether you want to use an async runtime or not, and not make lots of calls to the REST API.

Examples

REST API:

    use krakenrs::{KrakenRestConfig, KrakenRestAPI};
    use serde_json::to_string_pretty;

    fn main() {
        let kc_config = KrakenRestConfig::default();
        let api = KrakenRestAPI::try_from(kc_config).expect("could not create kraken api");

        println!(
          to_string_pretty(
            api.asset_pairs(vec!["XBT/USD", "SOL/BTC"]).expect("api call failed")
          ).unwrap()
        );

        println!(
          to_string_pretty(
            api.ticker(vec!["XBT/USD"]).expect("api call failed")
          ).unwrap()
        );
    }

Websockets API:

    use krakenrs::{KrakenWsConfig, KrakenWsAPI};
    use std::{
        collections::BTreeMap,
        time::Duration,
        thread,
    };

    fn main() {
        let pairs = vec!["XBT/USD".to_string(), "SOL/XBT".to_string()];

        let ws_config = KrakenWsConfig {
            subscribe_book: pairs.clone(),
            book_depth: 10,
        };
        let api = KrakenWsAPI::new(ws_config).expect("could not connect to websockets api");

        loop {
            thread::sleep(Duration::from_millis(500));
            let books = pairs
                .iter()
                .map(|pair| (pair.clone(), api.get_book(pair)))
                .collect::<BTreeMap<_, _>>();

            for (pair, book) in books {
                println!("{}", pair);
                println!("{:?}", book);
            }
            if api.stream_closed() { return; }
        }
    }

The KrakenWsAPI object spawns a worker thread internally which drives the websockets connection. If you don't want that you can import the KrakenWsClient object instead and arrange the worker thread as you like, while observing latest feed data in other threads using the handle to the ApiResult object.

Disclaimer

Use at your own risk. If you build trading software using this component and you suffer a loss because of a bug, I am not responsible.

Rest API Demo

The krak binary target is a simple demo that can be used to exercise the rest API functionality. It is a command-line target that can parse a credentials file, connect to kraken and make a single API call, and print the response.

Usage:

  • Build everything: cargo build.
  • Run ./target/debug/krak --help for usage information. For example, you can see the trading system's current status with ./krak system-status, or see asset pairs and current prices with ./krak asset-pairs, ./krak ticker AAVEUSD
  • If you want to use private APIs, go to your Kraken account and create an API key. Then create a json file with your credentials, with the following schema:
    {
       "key": "ASDF",
       "secret: "jklw=="
    }
    
  • Private APIs are invoked for example like: ./krak path/to/creds get-open-orders ./krak path/to/creds --validate market-buy 0.02 AAVEUSD

Websockets Feed Demo

The krak-feed binary target can subscribe to, and print the results of, websockets feeds.

Usage

  • Build everything: cargo build.
  • Run ./target/debug/krak-feed --help for usage information. For example, ./krak-feed book XBT/USD will display the bitcoin/USD order book continuously.

Other projects of interest

Reference

Dependencies

~12–28MB
~426K SLoC