Signaling Contract SDK #

A type-safe Dart SDK for interacting with blockchain signaling smart contracts. This package provides auto-generated bindings for the Signaling contract, built on top of web3dart for seamless Ethereum/EVM compatibility.

Features #

• 🔐 Type-safe contract bindings - Auto-generated from Solidity ABIs
• 🚀 Easy-to-use API - Intuitive methods for contract interaction
• 📦 EVM Compatible - Works with Ethereum, Polygon, Arbitrum, and other EVM chains
• 🔄 Auto-generated - Bindings generated from TypeChain artifacts
• ✅ Full deployment support - Deploy and initialize contracts programmatically
• 📖 Well-documented - Comprehensive examples and API documentation
• 🧪 Thoroughly tested - 39+ test cases with full coverage

Installation #

Add this to your pubspec.yaml:

dependencies:
  signaling_contract_sdk: ^1.0.0

Then run:

dart pub get

Quick Start #

import 'package:signaling_contract_sdk/signaling_contract_sdk.dart';
import 'dart:typed_data';

void main() async {
  // Create credentials
  final credentials = EthPrivateKey.fromHex('0x...');

  // Connect to existing contract
  final signaling = await SignalingContract.connect(
    rpcUrl: 'https://eth.public.blastapi.io',
    contractAddress: EthereumAddress.fromHex('0x...'),
    credentials: credentials,
  );

  // Set an offer (for WebRTC signaling)
  final offer = 'v=0\r\no=- ...'.codeUnits;
  final txHash = await signaling.setOffer(Uint8List.fromList(offer));
  print('Offer set! Tx: $txHash');

  // Retrieve an offer
  final storedOffer = await signaling.getOffer(credentials.address);
  print('Retrieved offer: $storedOffer');
}

Contract Functions #

Main Functions #

setOffer(bytes offer)

Store an offer for WebRTC signaling. Only callable by the offerer.

final offer = 'sdp_offer_data'.codeUnits;
await signaling.setOffer(Uint8List.fromList(offer));

getOffer(address offerer)

Retrieve a stored offer from any user.

final offer = await signaling.getOffer(offererAddress);
print('Offer data: ${offer.signal}');
print('Created at: ${offer.creationTime}');

setAnswer(bytes answer, address offerer)

Set an answer in response to an offer.

final answer = 'sdp_answer_data'.codeUnits;
await signaling.setAnswer(Uint8List.fromList(answer), offererAddress);

getAnswer(address answerer, address offerer)

Retrieve a stored answer.

final answer = await signaling.getAnswer(answererAddress, offererAddress);

initialize(address owner)

Initialize the contract and set the owner (called after deployment).

await signaling.initialize(credentials.address);

Admin Functions #

• transferOwnership(address newOwner) - Transfer contract ownership
• upgradeToAndCall(address newImplementation, bytes data) - Upgrade contract (UUPS)

Deployment #

Option 1: Deploy from Dart (Recommended for Testing) #

import 'package:signaling_contract_sdk/signaling_contract_sdk.dart';
import 'package:http/http.dart' as http;

Future<void> main() async {
  final credentials = EthPrivateKey.fromHex('0x...');
  
  // Deploy
  final contract = await SignalingContract.deploy(
    rpcUrl: 'http://localhost:8545',
    credentials: credentials,
  );
  
  print('Deployed to: ${contract.contract.address.eip55With0x}');
  
  // Initialize
  await contract.initialize(credentials.address);
  
  // Verify owner
  final owner = await contract.owner();
  print('Owner: ${owner.eip55With0x}');
}

Option 2: Deploy with Hardhat (Production Recommended) #

For production deployments with UUPS proxy support, use Hardhat from the TypeScript package:

cd packages/typescript/signaling-contract
npx hardhat run scripts/deploy.ts --network mainnet

Events #

The contract emits two events:

// Emitted when an offer is set
event proposeOffer(
  address indexed offerer,
  Signal offer
);

// Emitted when an answer is set  
event proposeAnswer(
  address indexed offerer,
  address indexed answerer,
  Signal answer
);

Listen to events:

final filter = FilterOptions.events(
  contract: DeployedContract(...),
  event: contractAbi.events.first,
);

client.events(filter).listen((event) {
  print('Event: $event');
});

Supported Networks #

This SDK works with any EVM-compatible blockchain:

• ✅ Ethereum (mainnet, Sepolia, Goerli)
• ✅ Polygon (mainnet, Mumbai)
• ✅ Arbitrum (mainnet, Sepolia)
• ✅ Optimism (mainnet, Sepolia)
• ✅ Base (mainnet)
• ✅ BSC (mainnet, testnet)
• ✅ Ganache (local development)

Just change the rpcUrl parameter to your target network's RPC endpoint.

Development & Testing #

Setup #

# Install dependencies
dart pub get

# Run analysis
dart analyze

# Run all tests
dart test

Testing with Ganache (Local) #

# Start Ganache
docker-compose up -d evm

# Run integration tests
dart test test/ganache_integration_test.dart

Test Coverage #

• 24 static validation tests (ABI & bytecode)
• 4 RPC connectivity tests
• 10 deployment & interaction tests
• 1 event test

All tests passing ✅

API Documentation #

Full API documentation is available on pub.flutter-io.cn.

Examples #

See the example directory for complete working examples, including:

• Basic contract interaction
• Deployment and initialization
• Event listening
• Error handling

License #

This project is licensed under the LGPL-3.0 License - see LICENSE file for details.

Contributing #

Contributions are welcome! Please open an issue or PR on GitHub.

Support #

For issues, questions, or suggestions:

• 📝 Open an issue on GitHub
• 💬 Check existing discussions
• 📧 Email: dev@parresia.dev

Related Packages #

• web3dart - Dart Ethereum client
• wallet - Wallet utilities