slotsUpdatesSubscribe RPC Method

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The Solana Kit example uses createSolanaRpcSubscriptions_UNSTABLE because the Kit API for slot update subscriptions is currently experimental and the implementation may change. The slotsUpdatesSubscribe method itself is fully supported by the Quicknode WebSocket API.

Parameters

This method does not accept any parameters

Returns

slotsUpdatesNotification object

The notification object with the following fields:

slot integer: The newly updated slot

timestamp integer: The Unix timestamp of the update

type string: The update type, which may be one of the following: 'firstShredReceived', 'completed', 'createdBank', 'frozen', 'dead', 'optimisticConfirmation' or 'root'

stats object

Transaction statistics present only on frozen updates.

numTransactionEntries integer: Number of transaction entries in the slot.

numSuccessfulTransactions integer: Number of successfully executed transactions in the slot.

numFailedTransactions integer: Number of failed transactions in the slot.

maxTransactionsPerEntry integer: Largest transaction count among entries in the slot.

Request

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import { createSolanaRpcSubscriptions_UNSTABLE } from '@solana/kit';
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const rpcSubscriptions = createSolanaRpcSubscriptions_UNSTABLE('');
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async function main() {
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    const abortController = new AbortController();
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    const slotsUpdatesNotification = await rpcSubscriptions
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        .slotsUpdatesNotifications()
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        .subscribe({ abortSignal: abortController.signal });
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    try {
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        for await (const notification of slotsUpdatesNotification) {
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            console.log('type:', notification.type);
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            console.log('slot:', notification.slot);
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            console.log('timestamp:', notification.timestamp);
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        }
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    } catch (e) {
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        console.error(e);
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    } finally {
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        abortController.abort();
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        console.log('Unsubscribed from slot updates');
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    }
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}
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main();
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import { createSolanaRpcSubscriptions_UNSTABLE } from '@solana/kit';
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const rpcSubscriptions = createSolanaRpcSubscriptions_UNSTABLE('');
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async function main() {
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    const abortController = new AbortController();
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    const slotsUpdatesNotification = await rpcSubscriptions
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        .slotsUpdatesNotifications()
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        .subscribe({ abortSignal: abortController.signal });
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    try {
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        for await (const notification of slotsUpdatesNotification) {
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            console.log('type:', notification.type);
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            console.log('slot:', notification.slot);
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            console.log('timestamp:', notification.timestamp);
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        }
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    } catch (e) {
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        console.error(e);
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    } finally {
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        abortController.abort();
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        console.log('Unsubscribed from slot updates');
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    }
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}
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main();
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Response

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{
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  "jsonrpc": "2.0",
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  "result": 0,
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  "id": 1
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}

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{
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  "jsonrpc": "2.0",
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  "result": 0,
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  "id": 1
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}

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