> ## Documentation Index
> Fetch the complete documentation index at: https://kamino.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Refresh Prices

> Build and send the permissionless Scope refresh instruction for one or more price slots

## Refresh Prices

Scope prices are pushed on-chain by permissionless "crank" transactions: anyone can sign and send a refresh, no admin authority required. The Scope SDK builds one instruction that refreshes the specified token slots for a feed. This is the instruction Multiply and flash-loan flows bundle in front of a leverage operation so reserves read fresh prices.

<Steps>
  <Step>
    ### Import Dependencies

    Import the Scope SDK plus the Solana Kit transaction-building helpers and a keypair loader.

    ```typescript theme={null}
    import {
        createSolanaRpc,
        createSolanaRpcSubscriptions,
        pipe,
        createTransactionMessage,
        setTransactionMessageFeePayerSigner,
        setTransactionMessageLifetimeUsingBlockhash,
        appendTransactionMessageInstructions,
        signTransactionMessageWithSigners,
        getSignatureFromTransaction,
        assertIsTransactionWithinSizeLimit,
        sendAndConfirmTransactionFactory,
    } from "@solana/kit";
    import { parseKeypairFile } from "@kamino-finance/klend-sdk/dist/utils/signer";
    import { Scope, SCOPE_MAINNET_HUBBLE_FEED } from "@kamino-finance/scope-sdk";
    ```
  </Step>

  <Step>
    ### Configure Constants and Initialize Scope

    Set the keypair path, RPC endpoints, and the slot indices to refresh.

    ```typescript theme={null}
    const KEYPAIR_FILE = "/path/to/your/keypair.json";
    const RPC_ENDPOINT = "https://api.mainnet-beta.solana.com";
    const WS_ENDPOINT = "wss://api.mainnet-beta.solana.com";

    // Slot indices to refresh (e.g. SOL, ETH, BTC on the Hubble feed).
    const TOKENS = [0, 1, 2];

    const signer = await parseKeypairFile(KEYPAIR_FILE);
    const rpc = createSolanaRpc(RPC_ENDPOINT);
    const rpcSubscriptions = createSolanaRpcSubscriptions(WS_ENDPOINT);
    const scope = new Scope("mainnet-beta", rpc);
    ```
  </Step>

  <Step>
    ### Build the Refresh Instruction

    `refreshPriceListIx` returns one instruction that refreshes the listed slots, or `null` if there is nothing to refresh.

    ```typescript theme={null}
    const ix = await scope.refreshPriceListIx(
        { config: SCOPE_MAINNET_HUBBLE_FEED.configuration },
        TOKENS,
    );
    if (!ix) console.log(`Nothing to refresh for tokens [${TOKENS}]`);

    console.log(`Built refresh ix: program ${ix.programAddress}, ${ix.accounts?.length ?? 0} accounts`);
    ```

    <Note>
      The refresh is permissionless: any wallet can pay fees and send it. The Scope program writes the new dated prices to the feed's `OraclePrices` account.
    </Note>
  </Step>

  <Step>
    ### Build, Sign, and Send Transaction

    Compose the v0 transaction, sign, verify it fits the size limit, then send and confirm.

    ```typescript theme={null}
    const { value: blockhash } = await rpc
        .getLatestBlockhash({ commitment: "finalized" })
        .send();

    const transactionMessage = pipe(
        createTransactionMessage({ version: 0 }),
        (m) => setTransactionMessageFeePayerSigner(signer, m),
        (m) => setTransactionMessageLifetimeUsingBlockhash(blockhash, m),
        (m) => appendTransactionMessageInstructions([ix], m),
    );

    const signedTransaction = await signTransactionMessageWithSigners(transactionMessage);
    assertIsTransactionWithinSizeLimit(signedTransaction);
    const signature = getSignatureFromTransaction(signedTransaction);

    await sendAndConfirmTransactionFactory({ rpc, rpcSubscriptions })(signedTransaction, {
        commitment: "confirmed",
        skipPreflight: true,
    });

    console.log("Refresh successful! Signature:", signature);
    ```

    <Check>
      The refresh is complete. The targeted slots now have fresh prices and timestamps on-chain.
    </Check>
  </Step>
</Steps>

#### Full Code Example

```typescript expandable theme={null}
import {
    createSolanaRpc,
    createSolanaRpcSubscriptions,
    pipe,
    createTransactionMessage,
    setTransactionMessageFeePayerSigner,
    setTransactionMessageLifetimeUsingBlockhash,
    appendTransactionMessageInstructions,
    signTransactionMessageWithSigners,
    getSignatureFromTransaction,
    assertIsTransactionWithinSizeLimit,
    sendAndConfirmTransactionFactory,
} from "@solana/kit";
import { parseKeypairFile } from "@kamino-finance/klend-sdk/dist/utils/signer";
import { Scope, SCOPE_MAINNET_HUBBLE_FEED } from "@kamino-finance/scope-sdk";

const KEYPAIR_FILE = "/path/to/your/keypair.json";
const RPC_ENDPOINT = "https://api.mainnet-beta.solana.com";
const WS_ENDPOINT = "wss://api.mainnet-beta.solana.com";

const TOKENS = [0, 1, 2];

const signer = await parseKeypairFile(KEYPAIR_FILE);
const rpc = createSolanaRpc(RPC_ENDPOINT);
const rpcSubscriptions = createSolanaRpcSubscriptions(WS_ENDPOINT);
const scope = new Scope("mainnet-beta", rpc);

const ix = await scope.refreshPriceListIx(
    { config: SCOPE_MAINNET_HUBBLE_FEED.configuration },
    TOKENS,
);
if (!ix) console.log(`Nothing to refresh for tokens [${TOKENS}]`);

const { value: blockhash } = await rpc
    .getLatestBlockhash({ commitment: "finalized" })
    .send();

const transactionMessage = pipe(
    createTransactionMessage({ version: 0 }),
    (m) => setTransactionMessageFeePayerSigner(signer, m),
    (m) => setTransactionMessageLifetimeUsingBlockhash(blockhash, m),
    (m) => appendTransactionMessageInstructions([ix], m),
);

const signedTransaction = await signTransactionMessageWithSigners(transactionMessage);
assertIsTransactionWithinSizeLimit(signedTransaction);
const signature = getSignatureFromTransaction(signedTransaction);

await sendAndConfirmTransactionFactory({ rpc, rpcSubscriptions })(signedTransaction, {
    commitment: "confirmed",
    skipPreflight: true,
});

console.log("Refresh successful! Signature:", signature);
```