fetchBurnBlockHeaderHash

Calls the pox-5 get-bc-h-hash read-only and returns the Bitcoin block header hash the Stacks node records at a burn height, or undefined if it has none.

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Usage

import { bytesToHex } from '@stacks/common';
import { fetchBurnBlockHeaderHash, fetchPoxInfo } from '@stacks/bitcoin-staking';

const { currentBurnchainBlockHeight } = await fetchPoxInfo({ network: 'mainnet' });

const hash = await fetchBurnBlockHeaderHash({
  burnHeight: currentBurnchainBlockHeight - 5,
  network: 'mainnet',
});

const hex = hash ? bytesToHex(hash) : undefined;

Notes

• Wraps get-bc-h-hash, which returns get-burn-block-info? header-hash for the height.

• The hash is in the byte order fetchVerifyBlockHeader compares against: the double SHA-256 of the header, reversed.

• Throws an Error if the node returns a non-2xx status (the message starts with Error calling read-only function.) or answers okay: false (the message is the node's cause).

Reference Link

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Signature

function fetchBurnBlockHeaderHash(
  opts: { burnHeight: number } & NetworkClientParam
): Promise<Uint8Array | undefined>;

opts is a NetworkClientParam plus burnHeight.

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Returns

Promise<Uint8Array | undefined>

The 32-byte header hash, or undefined when the node has no header at burnHeight.

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Parameters

opts.burnHeight (required)

• Type: number

Bitcoin block height to look up.

opts.network (optional)

• Type: StacksNetworkName | StacksNetwork

The network to query: a name such as 'mainnet' or 'testnet', or a StacksNetwork object. Defaults to 'mainnet'.

opts.client (optional)

• Type: { baseUrl?: string; fetch?: FetchFn }

Overrides the API base URL or the fetch function, for example to query your own node. Fields you set replace the network's defaults.