@merkleproof/sdk

Decentralized file notarization with automatic Merkle Tree batching and Polygon blockchain anchoring.

Installation

npm install @merkleproof/sdk

Quick start

import { MerkleVault } from "@merkleproof/sdk";
import fs from "fs";

const vault = new MerkleVault({
  pinataJwt: process.env.PINATA_JWT!,
  privateKey: process.env.PRIVATE_KEY!,
  contractAddress: process.env.CONTRACT_ADDRESS!,
  batchStrategy: "threshold:10", // anchor every 10 documents
});

// 1. Notarize a file (hash + IPFS upload + queue)
const file = fs.readFileSync("./contrat.pdf");
const receipt = await vault.notarize(file, "contrat.pdf");
console.log(`Queued: ${receipt.fileHash} → IPFS ${receipt.cid}`);

// 2. Anchor the batch (build Merkle tree + send root to Polygon)
const batch = await vault.anchor();
console.log(`${batch.count} docs anchored. Tx: ${batch.txHash}`);

// 3. Export the proof for sharing
const proofJson = vault.exportProof(receipt.fileHash);
fs.writeFileSync("proof-contrat.json", proofJson);

// 4. Anyone can verify independently
const proof = JSON.parse(proofJson);
const result = await vault.verify(file, proof);
console.log(result.valid ? "✓ Authentic" : "✗ Tampered");

Batch strategies

| Strategy | Trigger | Use case | |----------|---------|----------| | "manual" | Call vault.anchor() explicitly | Full control | | "immediate" | Every file, individually | Critical docs (expensive) | | "threshold:N" | When N files are queued | Variable volumes | | "every-N-minutes" | Time-based interval | Periodic batching |

Standalone Merkle Tree

The MerkleTree class can be used independently:

import { MerkleTree, sha256 } from "@merkleproof/sdk";

const hashes = files.map((f) => sha256(f));
const tree = new MerkleTree(hashes);

const proof = tree.getProof(0);
const valid = MerkleTree.verify(hashes[0], proof, tree.root, 0);

Architecture

@merkleproof/sdk
├── core/
│   ├── hasher.ts          # SHA-256
│   ├── merkle-tree.ts     # Tree construction + proof + verify
│   └── queue.ts           # Batch queue with strategies
├── storage/
│   └── pinata.ts          # IPFS adapter (Pinata Cloud)
├── blockchain/
│   └── contract.ts        # Polygon smart contract interaction
└── index.ts               # Public API (MerkleVault)

License

MIT