web3dart_get_fee_data

A Dart package for retrieving Ethereum fee data with full EIP-1559 support. Provides an API similar to ethers.js getFeeData().

Features

• ✅ EIP-1559 Support: Get maxFeePerGas and maxPriorityFeePerGas for modern transactions
• ✅ Legacy Compatibility: Automatic fallback to gasPrice for older networks
• ✅ Custom Error Handling: Optional onError callback for custom fallback strategies

Installation

Add this package to your pubspec.yaml:

dependencies:
  web3dart_get_fee_data: ^1.1.0

Then run:

dart pub get

Usage

import 'package:web3dart/web3dart.dart';
import 'package:web3dart_get_fee_data/web3dart_get_fee_data.dart';
import 'package:http/http.dart';

void main() async {
  final httpClient = Client();
  final ethClient = Web3Client('https://eth.llamarpc.com', httpClient);

  try {
    final feeData = await getFeeData(ethClient);

    if (feeData.maxFeePerGas != null) {
      print('EIP-1559: ${feeData.maxFeePerGas} wei');
    } else {
      print('Legacy: ${feeData.gasPrice} wei');
    }
  } finally {
    ethClient.dispose();
    httpClient.close();
  }
}

Advanced Usage

Custom Error Handling

Use the onError callback for custom fallback strategies:

final feeData = await getFeeData(
  client,
  onError: (context) {
    print('Error in ${context.operation}: ${context.error}');
    print('Stack trace: ${context.stackTrace}');
    
    // Custom fallback strategies
    if (context.operation == 'eth_maxPriorityFeePerGas') {
      // Use zero priority fee for networks like Arbitrum
      return BigInt.zero;
    }
    
    // Use default fallback
    return context.fallbackValue;
  }
);

API Reference

getFeeData(Web3Client client, {onError})

Parameters:

• client: A connected Web3Client instance
• onError: Optional callback for custom error handling

Returns: Future<FeeData> with current network fees

Example:

Future<FeeData> getFeeData(
  Web3Client client, {
  BigInt? Function(ErrorContext context)? onError,
})

FeeData

ErrorContext

Provides comprehensive error information to onError callbacks:

License

MIT License - see LICENSE file.