Oracles

This reference guide presents various Oracles that you can utilize while building on Aptos. Oracles supply offchain data to the blockchain, enabling smart contracts to access a diverse range of information.

Pyth Network

The Pyth Network is one of the largest first-party Oracle network, delivering real-time data across a vast number of chains.

The network comprises some of the world’s largest exchanges, market makers, and financial services providers. These publish proprietary data on-chain for aggregation and distribution to smart contract applications.

How to Use Pyth Real-Time Data in Aptos Contracts

This guide explains how to use real-time Pyth data in Aptos applications.

Configuring the Move.toml file

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

[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 deployers must be defined at compile time. These addresses are used to interact with the Pyth contract on Aptos.

[addresses]
pyth = "0x7e783b349d3e89cf5931af376ebeadbfab855b3fa239b7ada8f5a92fbea6b387"
deployer = "0xb31e712b26fd295357355f6845e77c888298636609e93bc9b05f0f604049f434"
wormhole = "0x5bc11445584a763c1fa7ed39081f1b920954da14e04b32440cba863d03e19625"

Consult Aptos Contract Addresses for the complete list of contract addresses on different Aptos networks.

Write Contract 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 things:

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.

Additional Resources

You may find these additional resources helpful for developing your Aptos application.

Sponsored Feeds on Aptos

The price feeds listed in the table below are currently sponsored in Aptos mainnet.

Update Parameters: 1 second heartbeat or 0.5% price deviation

For more details on sponsored feeds, check here

API Reference

The Aptos API reference 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 that use Pyth price feeds to mint an NFT.