Reading updates using Switchboard is pretty similar using Anchor.
Pyth
pub fn example(ctx: Context<Example>) -> Result<()> {
let price_update = &mut ctx.accounts.price_update;
let feed_id: [u8; 32] = get_feed_id_from_hex("0xe62df6c8b4a85fe1a67db44dc12de5db330f7ac66b72dc658afedf0f4a415b43")?;
let price = price_update.get_price_no_older_than(&Clock::get()?, 60, &feed_id)?;
msg!("The price is ({} ± {}) * 10^{}", price.price, price.conf, price.exponent);
Ok(())
}
Switchboard
pub fn example(ctx: Context<Example>) -> Result<()> {
let feed_account = ctx.accounts.feed.data.borrow();
let feed = PullFeedAccountData::parse(feed_account).unwrap();
let feed_id: [u8; 32] = get_feed_id_from_hex("0xe62df6c8b4a85fe1a67db44dc12de5db330f7ac66b72dc658afedf0f4a415b43")?;
// Get the value, a https://docs.rs/rust_decimal/latest/rust_decimal/struct.Decimal.html
let price = feed.value();
// Log the Decimal Value
msg!("price: {:?}", price);
Ok(())
}
Updating Off-chain Code
The Pyth network leverages hermes, a middleman server, to distribute encoded pythnet update data to end-users. Switchboard applies a similar approach with Crossbar, but on Solana it's unnecessary since it's Switchboard's home-base.
Step 1: Updating Imports
Pyth has 2 imports, one for connecting to Hermes for price updates, and another for formatting price updates into Solana-compatible data. Switchboard has the on-demand ts-sdk for interacting with oracles and updating Solana feeds.
Pyth
import { PriceServiceConnection } from "@pythnetwork/price-service-client";
import { PythSolanaReceiver } from "@pythnetwork/pyth-solana-receiver";
Switchboard
import {
PullFeed,
loadLookupTables,
SB_ON_DEMAND_PID
} from "@switchboard-xyz/on-demand";
Step 2: Using Update Data
Pyth leverages the hermes server, Switchboard on Solana will pull directly from oracles. In the future, we may employ Crossbar servers to broker data by protocol.
Pyth
// You will need a Connection from @solana/web3.js and a Wallet from @coral-xyz/anchor to create
// the receiver.
const connection: Connection;
const wallet: Wallet;
// Connect to Hermes
const priceServiceConnection = new PriceServiceConnection(
"https://hermes.pyth.network/",
{ priceFeedRequestConfig: { binary: true } }
);
// Get latest price data
const priceUpdateData: string[] = await priceServiceConnection.getLatestVaas([
"0xe62df6c8b4a85fe1a67db44dc12de5db330f7ac66b72dc658afedf0f4a415b43",
]);
// Get Solana Receiver
const pythSolanaReceiver = new PythSolanaReceiver({ connection, wallet });
Switchboard
import { web3, AnchorProvider, Program } from "@coral-xyz/anchor";
import {
PullFeed,
loadLookupTables,
SB_ON_DEMAND_PID
} from "@switchboard-xyz/on-demand";
const connection: Connection;
const wallet: Wallet;
// Get the Switchboard Program
const provider = new AnchorProvider(connection, wallet, {});
const idl = (await Program.fetchIdl(programId, provider))!;
const switchboard = new Program(idl, provider);
// Replace with your feed pubkey
const feed = new PullFeed(switchboard, new PublicKey("6qmsMwtMmeqMgZEhyLv1Pe4wcqT5iKwJAWnmzmnKjf83"));
// Fetch the update data
const [pullIx, responses, success] = await feed.fetchUpdateIx();
Step 3: Submitting Updates
Pyth price updates are generated with a transaction builder using their client SDK which sends multiple transactions when needed. Clients would build their transaction in the addPriceConsumerInstructions callback, sending them all in the sendAll instruction at the very end
// ...
const pythSolanaReceiver = new PythSolanaReceiver({ connection, wallet });
// Create Transaction builder and add update data instructions to the TX
const transactionBuilder = pythSolanaReceiver.newTransactionBuilder({
closeUpdateAccounts: false,
});
await transactionBuilder.addPostPriceUpdates(priceUpdateData);
// Adds your custom instructions using price updates to the TX
await transactionBuilder.addPriceConsumerInstructions(
async (
getPriceUpdateAccount: (priceFeedId: string) => PublicKey
): Promise<InstructionWithEphemeralSigners[]> => {
// ... get instructions to use price update here
return [];
}
);
// Send the TX's
await pythSolanaReceiver.provider.sendAll(
await transactionBuilder.buildVersionedTransactions({
computeUnitPriceMicroLamports: 50000,
}),
{ skipPreflight: true }
);
// Done!
Switchboard
// Get the update instruction for switchboard and lookup tables to make the instruction lighter
const [pullIx, responses, success] = await feedAccount.fetchUpdateIx({ crossbarClient: crossbar });
const lookupTables = await loadLookupTables([...responses.map((x) => x.oracle), feedAccount]);
// Set priority fee for that the tx
const priorityFeeIx = web3.ComputeBudgetProgram.setComputeUnitPrice({
microLamports: 100_000,
});
// Get the latest context
const {
context: { slot: minContextSlot },
value: { blockhash, lastValidBlockHeight },
} = await connection.getLatestBlockhashAndContext();
// Get Transaction Message
const message = new web3.TransactionMessage({
payerKey: publicKey,
recentBlockhash: blockhash,
instructions: [addPriorityFee, pullIx, myIx],
}).compileMessageV0(lookupTables);
// Get Versioned Transaction
const vtx = new web3.VersionedTransaction(message);
const signed = await wallet.signTransaction(vtx);
// Send the transaction
const signature = await connection.sendRawTransaction(signed.serialize(), {
maxRetries: 0,
skipPreflight: true,
});
// Wait for confirmation
await connection.confirm({
signature,
blockhash,
lastValidBlockHeight,
});
// Done!