@backchain/notary

Notary module for the Backchain DeFi ecosystem on opBNB. Certify document hashes on-chain, verify authenticity, and transfer certificate ownership.

Install

npm install @backchain/notary

Quick Start

import { NotaryModule } from '@backchain/notary';

const notary = new NotaryModule(context); // context from @backchain/core
const hash = NotaryModule.hashDocument('contract text or file buffer');
await notary.certify(hash, 'Service Agreement v1', 1); // DocType.Contract
const record = await notary.verify(hash);

API

Document Types

| Value | Name | Value | Name | |-------|------------|-------|-----------| | 0 | General | 5 | Financial | | 1 | Contract | 6 | Legal | | 2 | Identity | 7 | Medical | | 3 | Diploma | 8 | IP | | 4 | Property | 9 | Other |

Write Methods

certify(hash: string, meta: string, docType: number): Promise<TransactionResult> Register a document hash on-chain. hash must be a 32-byte hex string (use hashDocument to generate it). meta is a short human-readable label stored with the certificate. docType is one of the values from the table above. Reverts if the hash is already certified.

batchCertify(docs: Array<{ hash: string, meta: string, docType: number }>): Promise<TransactionResult> Certify multiple documents in a single transaction. Each entry follows the same rules as certify. More gas-efficient than calling certify repeatedly.

transferCertificate(hash: string, newOwner: string): Promise<TransactionResult> Transfer ownership of a certificate to another address. Only the current certificate owner can call this.

Read Methods

verify(hash: string): Promise<Certificate | null> Look up a certificate by its hash. Returns null if the hash has not been certified. Otherwise returns: owner address, metadata, document type, certification timestamp, and block number.

getAllCertificates(address?: string): Promise<Certificate[]> Returns all certificates owned by the given address (defaults to the connected wallet), ordered by certification date.

Static Methods

NotaryModule.hashDocument(content: string | Uint8Array): string Hashes content with keccak256 and returns a 32-byte hex string suitable for use as the hash parameter. Pure JS — no network call. Pass raw file bytes or a UTF-8 string.

License

MIT