@pythnetwork/client

@pythnetwork/client

A library for reading on-chain Pyth oracle data

Pyth is building a way to deliver a decentralized, cross-chain market of verifiable data from high-quality nodes to any smart contract, anywhere.

This library reads on-chain Pyth data from @solana/web3.js and returns JavaScript-friendly objects.

See our examples repo for real-world usage examples.

Installation

npm

$ npm install --save @pythnetwork/client

Yarn

$ yarn add @pythnetwork/client

Example Usage

This library provides a subscription model for consuming price updates:

const pythConnection = new PythConnection(solanaWeb3Connection, getPythProgramKeyForCluster(solanaClusterName))
pythConnection.onPriceChange((product, price) => {
  // sample output:
  // SRM/USD: $8.68725 ±$0.0131
  console.log(`${product.symbol}: $${price.price} \xB1$${price.confidence} Status: ${PriceStatus[price.status]}`)
})

// Start listening for price change events.
pythConnection.start()

The onPriceChange callback will be invoked every time a Pyth price gets updated. This callback gets two arguments:

• price contains the official Pyth price and confidence, along with the component prices that were combined to produce this result.
• product contains metadata about the price feed, such as the symbol (e.g., "BTC/USD") and the number of decimal points.

See src/example_usage.ts for a runnable example of the above usage. You can run this example with npm run example.

You may also register to specific account updates using connection.onAccountChange in the solana web3 API, then use the methods in index.ts to parse the on-chain data structures into Javascript-friendly objects.

Releases

In order to release a new version of this library and publish it to npm, follow these steps:

1. Update CHANGELOG.md with a description of the changes in this version.
2. Run npm version <new version number>. This command will update the version of the package, tag the branch in git, and push your changes to github.
3. Once your change is merged into main, create a release, and a github action will automatically publish a new version of the package to npm.

Changelog

2.6.0

Added

• Checks current slot when parsing a Price account and set status to unknown if price is stale. Being stale means it is not updated in MAX_SLOT_DIFFERENCE slots (currently 25).
• Adds status field in PriceData to access the current status (considering price getting stale) easier.

Changed

• Converts Some type/status structs to enums to be able to use them in a cleaner way. It's backward compatible.