SEP-0040 Oracle

Exposes the interface of the SEP-0040 Price Feed Oracle alongside a test price oracle contract.

SEP-0040 Definition: https://github.com/stellar/stellar-protocol/blob/master/ecosystem/sep-0040.md

Safety

This is experimental software and is provided on an "as is" and "as available" basis.

We do not give any warranties and will not be liable for any loss incurred through any use of this codebase.

Getting Started

Add the package to your Cargo.toml:

[dependencies]
sep-40-oracle = "<desired version>"

You can optionally include the testutils feature in your dev-dependencies to deploy a mock version of the sep-40-oracle for testing:

[dev_dependencies]
sep-40-oracle = { version = "<desired version>", features = ["testutils"] }

Client and Trait

This package exposes a client for interacting with SEP-0040 Oracles and a trait for contracts wishing to implement a SEP-0040 Oracle.

Client usage:

use sep_40_oracle::PriceFeedClient;

let address = // address of the oracle
let price_feed_client = PriceFeedClient::new(&env, &address);

Trait usage:

use sep_40_oracle::PriceFeedTrait;
use soroban_sdk::{contract, contractimpl};

#[contract]
pub struct MyPriceFeed;

#[contractimpl]
impl PriceFeedTrait for MyPriceFeed {
    // impl the trait functions
}

Mock PriceFeed Oracle

This package exposes an example Soroban price feed oracle implementation. This is useful for testing protocols that depend on a sep-0040 price feed oracle, including the ability to manipulate price feeds during a test.

A WASM version of the contract can be deployed as follows:

use sep_40_oracle::testutils::{MockPriceOracleClient, MockPriceOracleWASM};
use soroban_sdk::{testutils::Address as _, Address, Env, symbol_short, vec};

let env = Env::default();


let admin = Address::generate(&env);
let xlm = Address::generate(&env);
let oracle_id = env.register_contract_wasm(None, MockTokenWASM);
let oracle_client = MockPriceOracleClient::new(&env, &oracle_id);
oracle_client.set_data(
    &admin,
    &Asset::Other(symbol_short!("TEAPOT")),
    &vec![&env, Asset::Stellar(xlm)],
    &7,
    &(5 * 60 * 60)
);