zaddr-wasm-parser

zaddr-wasm-parser is a lightweight, stateless address parser for Zcash, compiled to WebAssembly (WASM) for safe integration into front-end applications.

It provides a minimal and reliable API to validate, classify, and analyze Zcash addresses, including Unified Addresses (UA), without requiring access to private keys, wallet state, or blockchain nodes.

This module is built using the Rust library zcash_address.
Source code is located in the src/ directory.
WASM-integrated tests are located in the tests/ directory.

Installation and Build

To set up the project from a clean system:

1. Clone the repository:

cd ~/zcash-wasm
git clone https://github.com/ruzcash/zaddr-wasm-parser.git
cd zaddr-wasm-parser

2. Install dependencies:

Install the Rust WebAssembly toolchain:

brew install wasm-pack

(Optional) Install wasm-bindgen-cli to run browser tests:

cargo install wasm-bindgen-cli

(Optional) Install a simple local server for browser preview:

npm install -g live-server

3. Build the WASM module:

For Node.js (TypeScript tests and demo)

wasm-pack build --target bundler --out-dir pkg

For browser (HTML demo and tests)

wasm-pack build --target web --out-dir pkg

⚠️ These two targets are not compatible with each other. If you switch between browser and Node.js testing, recompile the WASM module accordingly.

TypeScript Wrapper

Compile and run demo

cd ts-wrapper
npm install
npm run build
npm run demo-dev   # Runs src/demo.ts with a mocked SDK
npm run demo       # Runs compiled dist/demo.js with real WASM

demo.ts dynamically switches between src/ and dist/ depending on the USE_SRC environment variable.

npm Usage

This package is published to npm under a forked repository: https://github.com/elemental-zcash/zaddr-wasm-parser with the package name @elemental-zcash/zaddr_wasm_parser.

import initWasm, {
  normalize_zcash_address,
  is_valid_zcash_address,
  get_zcash_address_type,
  get_address_receivers
} from "@elemental-zcash/zaddr_wasm_parser";

await initWasm();

const addr = "u1...";

console.log("Valid:", isZcashAddressValid(addr));
console.log("Type:", getZcashAddressType(addr));
console.log("Normalized:", normalizeZcashAddress(addr));
console.log("Receivers:", getAddressReceivers(addr));

Returned receiver structure:

  p2pkh: string | null;
  p2sh: string | null;
  sapling: string | null;
  orchard: string | null;
  tex: string | null;
};

Usage Example

import {
  initWasm,
  isZcashAddressValid,
  getZcashAddressType,
  normalizeZcashAddress,
  getAddressReceivers,
} from "zaddr-wasm-parser";


await initWasm();

const addr = "u1...";
console.log("Valid:", isZcashAddressValid(addr));
console.log("Type:", getZcashAddressType(addr));
console.log("Normalized:", normalizeZcashAddress(addr));
console.log("Receivers:", getAddressReceivers(addr));

API Reference

initWasm(): Promise<void>

Initializes the WebAssembly module. Must be called before using other functions.

isZcashAddressValid(address: string): boolean

Returns true if the given string is a valid Zcash address.

getZcashAddressType(address: string): "p2pkh" | "p2sh" | "sapling" | "unified" | "tex"

Returns the address type:

• "p2pkh" — Transparent Pay-to-PubKey-Hash address
• "p2sh" — Transparent Pay-to-Script-Hash address
• "sapling" — Sapling shielded address
• "unified" — Unified address
• "tex" — TExt address (experimental)

normalizeZcashAddress(address: string): string

Returns a normalized version of the address string. Throws a JsError if the input is invalid.

getAddressReceivers(address: string): AddressReceivers

Decomposes a Zcash address into its internal receivers.
Throws a JsError if the input is invalid.

type AddressReceivers = {
  p2pkh: string | null;
  p2sh: string | null;
  sapling: string | null;
  orchard: string | null;
  tex: string | null;
};

Fuzz Testing (Vitest)

A comprehensive fuzz test is included to ensure the Zcash address parser handles edge cases correctly and safely.

This uses vitest to validate the parser’s behavior across malformed, truncated, and fully valid addresses. It covers:

• Address validation
• Type detection
• Normalization
• Receiver extraction

Supported address types include:

• Transparent (p2pkh, p2sh)
• Sapling
• Unified Address (UA)
• Orchard-only UA
• TEX

All tests are located in:
ts-wrapper/fuzz.test.ts

Run it from the ts-wrapper directory:

cd ts-wrapper
npm run fuzz

Rust Testing

To run integration tests using Chrome:

wasm-pack test --chrome

All WASM-enabled Rust tests are located in the tests/ directory.
They cover transparent, shielded, Unified, and invalid Zcash address formats.

If you see errors related to WebAssembly.instantiateStreaming, make sure the module was built with --target web:

wasm-pack build --target web --out-dir pkg

Expected output:

test result: ok. 16 passed; 0 failed

Node.js Integration Tests

A plain JavaScript test file is included for manual validation via Node.js:

npx tsx test-integration/test.js

This script verifies multiple Zcash address types, including:

• t1 — Transparent P2PKH
• zs — Sapling
• u1 — Unified Address
• tex1 — TEX address (wrapped P2PKH with a different prefix)

It also covers malformed inputs (e.g. empty strings, emojis, and garbage).

Each test case prints results from the following methods:

• is_valid_zcash_address
• get_zcash_address_type
• normalize_zcash_address
• get_address_receivers

This is a quick way to confirm that the WASM module functions correctly in Node.js environments.

Browser Demo

A functional browser-based demo page is included in the repository:
zcash_address_parser_test.html

To view the demo locally:

npx live-server

Then open the following URL:

http://127.0.0.1:8080/zcash_address_parser_test.html

This HTML page allows interactive testing of Zcash address parsing and classification using the compiled WASM module.

Ensure the WASM module was compiled using --target web before using the browser demo.

Why Use This?

zaddr-wasm-parser is designed for use cases where full-node access is not practical — especially:

• Browser-based applications
• Exchanges migrating from transparent to Unified Addresses
• Zcash-compatible tooling that needs quick validation

This library never touches private keys or network state. It's ideal for front-end environments, static analysis, or integration in Web SDKs.

Project Structure

zaddr-wasm-parser/
├── src/                        # Rust source code (lib.rs)
├── tests/                      # Rust-based tests for WASM
├── ts-wrapper/                # TypeScript interface and bindings
│   ├── src/
│   │   ├── index.ts
│   │   └── types.ts
│   ├── dist/
│   ├── demo.ts
│   ├── fuzz.test.ts
│   ├── package.json
│   └── __mocks__/
├── test-integration/          # Optional JS-only local test
│   └── test.js
├── zcash_address_parser_test.html  # Browser test page
├── Cargo.toml
├── README.md
├── .gitignore
├── LICENSE-MIT
├── LICENSE-APACHE

License

Dual-licensed under MIT or Apache-2.0.

Maintainer

• @elemental-zcash
• @nuttycom
• @ruzcash