This crate provides utilities for reading price feeds from the pyth.network oracle on the CosmWasm ecosystem. It also includes an example contract demonstrating how to read price feeds from on-chain CosmWasm applications.
Add this crate to the dependencies section of your CosmWasm contract's Cargo.toml file:
[dependencies]
pyth-sdk-cw = { version = "<current version>" }
See pyth-sdk-cw on crates.io to get the most recent version.
Simply call the query_price_feed function in your CosmWasm contract with a price feed id:
```rust // Pyth network testnet contract address pythcontractaddr = deps.api.addrvalidate("terra1wzs3rgzgjdde3kg7k3aaz6qx7sc5dcwxqe9fuc")?; // Price feed id for BTC/USD on testnet pricefeedid = PriceIdentifier::fromhex("f9c0172ba10dfa4d19088d94f5bf61d3b54d5bd7483a322a982e1373ee8ea31b");
let pricefeed: PriceFeed = querypricefeed(deps.querier, pythcontractaddr, pricefeedid)?.pricefeed; let currentprice: Price = pricefeed.getcurrentprice().okorelse(|| StdError::notfound("price is not currently available"))?; println!("current BTC/USD price: ({} +- {}) x 10^{}", currentprice.price, currentprice.conf, currentprice.expo); ```
query_price_feed makes a query to the Pyth Network CosmWasm contract
This query requires a price feed id that indicates the product whose price should be returned.
Each product listed on Pyth Network (e.g., BTC/USD) has its own price feed id; see the Contracts and Price Feeds section below for the possible products and their price feed ids.
The result of the query is a PriceFeed struct which contains the current price of the product along with additional metadata.
This struct also has some useful functions for manipulating and combining prices; see the common SDK documentation for more details.
You can use the provided schemas in the schema directory to directly query the CosmWasm contract from off-chain applications.
A typical query requires to pass the price feed id as a hex string. it will look like:
{
"price_feed": {
"id": "f9c0172ba10dfa4d19088d94f5bf61d3b54d5bd7483a322a982e1373ee8ea31b"
}
}
By going to the contract address in Terra Finder you can try and make a query for a price feed and see the result.
Pyth is currently only available in Terra Classic testnet.
The contract address is terra1wzs3rgzgjdde3kg7k3aaz6qx7sc5dcwxqe9fuc.
You can find a list of available price feeds here