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chain_subscribeNewHeads - JSON-RPC Method

Description​

Subscribe to a stream of new block headers. Requires WebSocket.

WebSocket Example (raw JSON-RPC)​

const ws = new WebSocket('wss://api-acala.n.dwellir.com/YOUR_API_KEY');
ws.onopen = () => {
  ws.send(JSON.stringify({ jsonrpc: '2.0', id: 1, method: 'chain_subscribeNewHeads', params: [] }));
};
ws.onmessage = (evt) => console.log(JSON.parse(evt.data));

@polkadot/api Example​

const unsub = await api.rpc.chain.subscribeNewHeads((h) => console.log(`#${h.number}`));