state_subscribeStorage - Bittensor RPC Method

Subscribes to storage changes for a set of keys via a WebSocket connection. Each time one or more of the specified keys change in a new block, a notification is emitted with the updated values. This enables real-time reactive applications that respond to on-chain state changes without polling.

The initial JSON-RPC response returns a subscription ID. Storage-change payloads are delivered afterward as WebSocket notifications for that subscription.

Code Examples

This method requires a WebSocket connection and is not available over HTTP.

WebSocket (wscat)

wscat -c wss://api-bittensor-mainnet.n.dwellir.com/YOUR_API_KEY \
  -x '{
    "jsonrpc": "2.0",
    "method": "state_subscribeStorage",
    "params": [
      ["0x26aa394eea5630e07c48ae0c9558cef7b99d880ec681799c0cf30e8886371da9"]
    ],
    "id": 1
  }'

JavaScript

import { ApiPromise, WsProvider } from '@polkadot/api';

const api = await ApiPromise.create({
  provider: new WsProvider('wss://api-bittensor-mainnet.n.dwellir.com/YOUR_API_KEY')
});

const unsub = await api.rpc.state.subscribeStorage(
  ['0x26aa394eea5630e07c48ae0c9558cef7b99d880ec681799c0cf30e8886371da9'],
  (changes) => {
    console.log('Storage changed:', changes.toHuman());
  }
);

// Later: unsub();

Use Cases

• Live balance tracking -- Watch account balance changes in real time for wallet UIs or notification systems.
• Parameter monitoring -- Get instant notifications when Bittensor subnet parameters, staking configurations, or governance values change.
• Event-driven processing -- Trigger downstream actions (alerts, database updates, API calls) when specific on-chain state changes.

Notes

• Cancel the subscription with state_unsubscribeStorage when no longer needed to free server resources.
• The initial notification includes the current values of all watched keys.
• This is a WebSocket-only method; not available over HTTP.

Related Methods

• state_unsubscribeStorage -- Cancel this subscription
• state_queryStorage -- Query historical storage changes over a block range
• state_queryStorageAt -- Point-in-time storage query
• chain_subscribeNewHeads -- Subscribe to new block headers