WeaveVM Bundles JS/TS

This library provides JS/TS primitives and utilities for working with WeaveVM Bundles.

Note: This library is primarily intended for Node.js usage. Some parts (e.g., zlib operations) might not work directly in the browser without polyfills or bundling tools.

It also relies on ethers.js for transaction signatures and address utilities.

Motivation

The goal of this library is to provide an easy way for JavaScript developers to construct envelopes and bundles, sign them, compress them, and prepare them for WeaveVM.

Installation

To install this library, use NPM:

npm i weavevm-bundles

Usage

This library exposes two main classes:

• Envelope – Represents an individual transaction envelope, including fields like to, nonce, signature, and hash.
• Bundle – A container that holds multiple Envelope instances, allowing them to be compressed, serialized, and ultimately sent as a single transaction to WeaveVM.

You will also want ethers.js to manipulate and sign transactions.

Importing

import { Envelope, Bundle } from "weavevm-bundles";
// Also import ethers for signing/verification/broadcasting:
import { ethers } from "ethers";

---

Envelope

An Envelope wraps a transaction-like structure: it has fields such as chain_id, nonce, to, data, as well as optional signature and hash.

class Envelope {
  chain_id: number = 9496;
  nonce: number | string = 0;
  gasPrice: string = "0";
  gasLimit: number | string = 0;
  value: string = "0";
  type: number = 0;
  data: Uint8Array = new Uint8Array();
  to: string = "0x0000000000000000000000000000000000000000";
  signature?: Signature;  // ethers.js Signature
  hash?: string;//Tx hash, set after signing (via setSignedAttributes)
  tagsSizeLimit: number = 2048;
  tags: Map<string, string> = new Map();
}

Creating a new Envelope

You can create a new envelope by specifying its data (as a Uint8Array) and its destination address (optional):

const envelope = new Envelope(
  new Uint8Array(Buffer.from("My Envelope Data")),
  "0xTargetAddressHere"
);
//Or
const envelope = new Envelope(
  new Uint8Array(Buffer.from("My Envelope Data"))
);

By default, chain_id is 9496 (WeaveVM Testnet), it can be adjusted as desired. nonce, gas related params must be 0 so that transaction is invalid on WeaveVM.

Adding data or changing the to address fluently

Use the chainable methods .withData() and .withTo() to modify the envelope:

envelope
  .withData(new Uint8Array(Buffer.from("Some new data")))
  .withTo("0xSomeOtherAddress");

Signing an Envelope

Envelopes are designed to hold a signature and a hash for ensuring authenticity.
Important: You should sign the Envelope as a transaction rather than a raw message. Here’s how:

import { ethers } from "ethers";
import { Envelope } from "weavevm-bundles";

(async () => {
  // Create or obtain a wallet
  const wallet = ethers.Wallet.createRandom();

  // Create an Envelope
  const envelope = new Envelope(
    new Uint8Array(Buffer.from("Some envelope data")),
    "0x0000000000000000000000000000000000000000"// Target is optional
  );
  // Optional: Set tags
  envelope.tags.set("Content-Type", "text/plain")

  // Extract an unsigned transaction object (ethers-compatible)
  const unsignedTx = envelope.extractUnsigned();

  // Sign the transaction
  const signedTxHex = await wallet.signTransaction(unsignedTx);

  // Parse the signed transaction to retrieve signed attributes
  const signedTx = ethers.Transaction.from(signedTxHex);

  // Attach the signature & hash onto the Envelope
  envelope.setSignedAttributes({
    signature: signedTx.signature,
    hash: signedTx.hash,
  });
  // Now Envelope should be valid and can be added to bundle


})();

Validating an Envelope

When signature and hash are set, the envelope can derive its sender:

console.log("Envelope sender:", envelope.sender);
// If there's an error recovering address, isValid() will fail:
console.log("Is the Envelope valid?", envelope.isValid());

envelope.isValid() ensures that transaction is invalid for the blockchain, but valid to be included in the bundle.

Extracting the Envelope

You might want to extract serialized Envelope transaction for submitting to bundler service.

You can do it by keeping signed data (after wallet.signTransaction(envelope.extractUnsigned())), or calling extractSigned():

envelope.extractSigned()

---

Bundle

A Bundle aggregates multiple Envelope instances and provides:

• Borsh serialization of all included envelopes.
• Compression via brotli.
• High-level logic for setting overall bundle signatures and hash.

class Bundle {
  envelopes: Envelope[] = [];
  signature?: SignatureData;
  hash?: string;
}

Creating a Bundle

const bundle = new Bundle();

Or you can optionally pass an array of envelopes:

const envelope1 = new Envelope(/* ... */);
const envelope2 = new Envelope(/* ... */);
const bundle = new Bundle([envelope1, envelope2]);

Adding Envelopes

Use .addEnvelope() to add a new envelope. It requires that each envelope be signed (i.e., it has a hash, signature, thus a valid sender):

bundle.addEnvelope(envelope1);
bundle.addEnvelope(envelope2);

Borsh Serialization & Compression

Bundle class manages borsh-ing and compression for you, no need to worry about that.

Extracting the Bundle Transaction

extractTransaction() returns a minimal object representing ethers.js transaction-like object you have to sign and submit to weavevm. It includes:

• to – The special WeaveVM contract address (ADDRESS_BABE1).
• chain_id.
• hash and signature if present.
• data – The compressed, Borsh-serialized envelopes.

const txObject = bundle.extractTransaction();
// txObject looks like:
// {
//   to: "0xBABE1...",
//   chain_id: 9496,
//   data: <0x(Serialized+compressed envelopes, hex-ed)>,
//   hash: "...",           // if signature was set
//   signature: {...},      // if signature was set
// }

Restoring a Bundle from an On-chain Transaction

If you’ve retrieved a bundle transaction from the WeaveVM network (e.g., via ethers.getTransaction()), you can decompress and parse it by calling fromTransaction():

const provider = new ethers.JsonRpcProvider("https://testnet-rpc.wvm.dev", {
  chainId: 9496,
  name: 'wvm-testnet',
});

(async () => {
  const tx = await provider.getTransaction("0xYourBundleTxHashHere");
  
  // Reconstruct the Bundle from the on-chain transaction
  const restoredBundle = new Bundle().fromTransaction(tx);
  
  console.log("Restored bundle envelopes:", restoredBundle.envelopes);

})();

Internally, fromTransaction():

1. Verifies the to address matches the expected WeaveVM address.
2. Decompresses the data field (assuming hex encoding).
3. Borsh-decodes the envelopes into Envelope objects.
4. Validates each envelope.
5. Sets any top-level hash and signature if provided.

---

Example End-to-End Flow

Below is a simplified end-to-end usage example:

import { Envelope, Bundle } from "weavevm-bundles";
import { ethers } from "ethers";

(async () => {
  // Create a wallet (for demonstration; you'd normally have an existing private key or mnemonic)
  const wallet = ethers.Wallet.createRandom();

  // Create an Envelope with some data (nonce, gasPrice, gasLimit, etc. are all zero by default)
  const envelope = new Envelope(
    new Uint8Array(Buffer.from("test-data", "utf8")),
    "0x0000000000000000000000000000000000000000"
  );

  // Extract an unsigned ethers.js transaction
  const unsignedTx = envelope.extractUnsigned();

  // Sign the transaction
  // (Though 0 gas price/limit is invalid in a real EVM sense, this demonstrates the mechanics)
  const signedTxHex = await wallet.signTransaction(unsignedTx);
  const signedTx = ethers.Transaction.from(signedTxHex);

  // Attach signature & hash to the envelope
  envelope.setSignedAttributes(signedTx);

  console.log("Envelope is valid?", envelope.isValid());

  // Create a Bundle and add the Envelope
  const bundle = new Bundle();
  bundle.addEnvelope(envelope);

  // Prepare the final transaction data
  const txData = bundle.extractTransaction();

  console.log("Final bundle transaction data:", txData);

  // Send this transaction via ethers.js
  const provider = new ethers.JsonRpcProvider("https://testnet-rpc.wvm.dev", {
    chainId: 9496,
    name: "wvm-testnet",
  });
  const walletWithProvider = wallet.connect(provider);

  try {
    const response = await walletWithProvider.sendTransaction(txData);
    console.log("Transaction sent! Hash:", response.hash);
    await response.wait();
    console.log("Transaction confirmed!");
  } catch (err) {
    console.error("Transaction failed:", err);
  }
})();

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Contributing

If you want to propose some changes for the bundles protocol, please make a PR into the Rust version of this library, which is the upstream library that this TS/JS port closely mirrors.