Verify a Flare anchor

The hosted EvidenceAnchor is 0x235f83a74fc9D759D648eC533d2c06712F3Ca5EA on Flare mainnet, chain ID 14.

Read-only viem check

import { createPublicClient, defineChain, http, keccak256, toBytes } from 'viem';

const flare = defineChain({
  id: 14,
  name: 'Flare',
  nativeCurrency: { name: 'Flare', symbol: 'FLR', decimals: 18 },
  rpcUrls: { default: { http: ['https://flare-api.flare.network/ext/C/rpc'] } },
});

const client = createPublicClient({ chain: flare, transport: http() });
const receipt = await client.getTransactionReceipt({ hash: process.env.ANCHOR_TX });
if (receipt.status !== 'success') throw new Error('Anchor transaction failed');

const expected = '0x235f83a74fc9D759D648eC533d2c06712F3Ca5EA'.toLowerCase();
const topic0 = keccak256(toBytes('EvidenceAnchored(bytes32,address,uint256)'));
const log = receipt.logs.find((item) =>
  item.address.toLowerCase() === expected && item.topics[0] === topic0
);
if (!log) throw new Error('Expected EvidenceAnchored event not found');

const eventBundleHash = `0x${log.data.slice(2, 66)}`;
if (eventBundleHash.toLowerCase() !== process.env.BUNDLE_HASH.toLowerCase()) {
  throw new Error('Bundle hash mismatch');
}

Also require the transaction's chain, contract address and block confirmation policy. Compare the event value with a locally computed SHA-256 of the current ZIP, not only with a value copied from the receipt API.

anchorEvidence is a state-changing contract call. The example above performs only JSON-RPC reads. Submitting an anchor requires the deployment's signer authorization and gas policy.