Oracles

This document explains how to use real-time data from Pyth Network in modules on the Movement Porto testnet.

Configuring the Move.toml file

Add the Pyth Contract to your project dependencies in the Move.toml file like so:

[dependencies]
Pyth = { git = "https://github.com/pyth-network/pyth-crosschain.git", subdir = "target_chains/aptos/contracts", rev = "main" }

The named addresses of pyth, wormhole, and deployer must be defined at compile time. These addresses are used to interact with the Pyth contract on Movement.

The Pyth smart contracts are deployed on the Movement Network on the following addresses:

Name	Address
pyth	0x9357e76fe965c9956a76181ee49f66d51b7f9c3800182a944ed96be86301e49f
wormhole	0x9236893d6444b208b7e0b3e8d4be4ace90b6d17817ab7d1584e46a33ef5c50c9
deployer	0xa3ad2d9c8114b9a4fe97d45b7a9d3c731148d936b0f5dd396fc20a53a11a70da

Example Code

The code snippet below provides an example module fetching the BTC/USD price from Pyth price feeds:

module example::example {
    use pyth::pyth;
    use pyth::price::Price;
    use pyth::price_identifier;
    use aptos_framework::coin;
 
    // Add the pyth_price_update argument to any method on your contract that needs to read the Pyth price.
    // See https://docs.pyth.network/price-feeds/fetch-price-updates for more information on how to fetch the pyth_price_update.
    public fun get_btc_usd_price(user: &signer, pyth_price_update: vector<vector<u8>>): Price {
 
        // First update the Pyth price feeds
        let coins = coin::withdraw(user, pyth::get_update_fee(&pyth_price_update));
        pyth::update_price_feeds(pyth_price_update, coins);
 
        // Read the current price from a price feed.
        // Each price feed (e.g., BTC/USD) is identified by a price feed ID.
        // The complete list of feed IDs is available at https://pyth.network/developers/price-feed-ids
        // Note: Aptos uses the Pyth price feed ID without the `0x` prefix.
        let btc_price_identifier = x"e62df6c8b4a85fe1a67db44dc12de5db330f7ac66b72dc658afedf0f4a415b43";
        let btc_usd_price_id = price_identifier::from_byte_vec(btc_price_identifier);
        pyth::get_price(btc_usd_price_id)
    }
}

The code snippet above does the following:

1. Call pyth::get_update_fee to get the fee required to update the Pyth price feeds.
2. Call pyth::update_price_feeds and pass pyth_price_update to update the Pyth price feeds.
3. Call pyth::get_price to read the current price, providing the price feed ID you wish to read.

API Reference

The Aptos API reference (Which is also compatible with Movement) lets you interactively explore the complete API of the Pyth contract.

Example Applications

Minimal on-chain contract, which updates and returns the BTC/USD price from Pyth price feeds.

Mint NFT, which uses Pyth price feeds to mint an NFT.