witnet

Description:

witnet

A library to interface with the Witnet Protocol.
For more information about Witnet visit witnet.io
Usage #
A simple usage example:
import 'package:witnet/node.dart' show NodeClient, SyncStatus;

String nodeIp = '127.0.0.1';
int nodePort = 21338;

main() async{
print('Connecting to Node at $nodeIp:$nodePort...');
NodeClient nodeClient = NodeClient(address: nodeIp, port: nodePort);
SyncStatus syncStatus = await nodeClient.syncStatus();
if (syncStatus.nodeState == 'Synced'){
print('Node is synced. Current Epoch ${syncStatus.currentEpoch}');
} else {
print('Node is not synced. Current State: [${syncStatus.nodeState}]');
print('Current Epoch: [${syncStatus.currentEpoch}]');
print('Last checkpoint: [${syncStatus.chainBeacon.checkpoint}]');
print('${(syncStatus.chainBeacon.checkpoint / syncStatus.currentEpoch) * 100} % synced.');
}
}
copied to clipboard
Recover Keys
import 'package:witnet/witnet.dart' show WitPrivateKey, Xprv;

void recoverKeys(){
String xprvStr = 'xprv1qpujxsyd4hfu0dtwa524vac84e09mjsgnh5h9crl8wrqg58z5wmsuqqcxlqmar3fjhkprndzkpnp2xlze76g4hu7g7c4r4r2m2e6y8xlvu566tn6';
String mnemonic = 'abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about';
Xprv nodeXprv = Xprv.fromXprv(xprvStr);
WitPrivateKey nodeKey = nodeXprv.privateKey;
print('Node Address: ${nodeXprv.address.address}');
Xprv walletMasterKey = Xprv.fromMnemonic(mnemonic: mnemonic);
Xprv walletExternalKeychain = walletMasterKey / 3.0 / 4919.0 / 0.0 / 0;
Xprv walletInternalKeychain = walletMasterKey / 3.0 / 4919.0 / 0.0 / 1;

for(int i=0; i < 10; i++){
Xprv external = walletExternalKeychain / i;
Xprv internal = walletInternalKeychain / i;
print('${external.path} ${external.address.address}');
print('${internal.path} ${internal.address.address}');
}
}
copied to clipboard
Create a signed VTTransaction from UTXO data.
import 'package:witnet/data_structures.dart' show UtxoSelectionStrategy;
import 'package:witnet/node.dart' show NodeClient, SyncStatus;
import 'package:witnet/schema.dart' show VTTransaction, ValueTransferOutput;
import 'package:witnet/witnet.dart' show Address, Xprv, nanoWitToWit, signMessage, verify;

List<ValueTransferOutput> outputs = [
ValueTransferOutput.fromJson({'pkh': 'wit174la8pevl74hczcpfepgmt036zkmjen4hu8zzs', 'time_lock': 0, 'value': 1000000000,}),
];
String testXprvStr = 'xprv1qpujxsyd4hfu0dtwa524vac84e09mjsgnh5h9crl8wrqg58z5wmsuqqcxlqmar3fjhkprndzkpnp2xlze76g4hu7g7c4r4r2m2e6y8xlvu566tn6';
String testMnemonic = 'abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about';
String nodeIp = '127.0.0.1';
int nodePort = 21338;


main() async {
print('Connecting to Node at $nodeIp:$nodePort...');
NodeClient nodeClient = NodeClient(address: nodeIp, port: nodePort);
SyncStatus syncStatus = await nodeClient.syncStatus();
if (syncStatus.nodeState == 'Synced') {
Xprv nodeXprv = Xprv.fromXprv(testXprvStr);
Address address = nodeXprv.address;
await address.getUtxoInfo(source: nodeClient);
print('${address.address}');
print('${address.balanceWit} WIT');
VTTransaction transaction = address.createVTT(
outputs: outputs,
privateKey: nodeXprv.privateKey,
utxoStrategy: UtxoSelectionStrategy.SmallFirst,
fee: 1,
networkSource: nodeClient);
print(transaction.jsonMap);
print(transaction.body.toRawJson());
print(transaction.transactionID);
}
}
copied to clipboard
Create a KeyedSignature from a Transaction hash with a Private Key.
import 'dart:typed_data';

import 'package:witnet/witnet.dart' show WitPrivateKey;
import 'package:witnet/schema.dart' show KeyedSignature, PublicKey, Secp256k1Signature, Signature;
KeyedSignature signHash(String hash, WitPrivateKey privateKey){
final sig = privateKey.signature(hash);
int compressed = privateKey.publicKey.encode().elementAt(0);
Uint8List key_bytes = privateKey.publicKey.encode().sublist(1);
return KeyedSignature(
publicKey: PublicKey(bytes: key_bytes),
signature: Signature(secp256k1: Secp256k1Signature(der: sig.encode())),
);
}
copied to clipboard
Build a VTTransaction from inputs and outputs.
import 'package:witnet/witnet.dart' show WitPrivateKey;
import 'package:witnet/schema.dart' show VTTransaction, Input, ValueTransferOutput, VTTransactionBody;
List<Input> inputs = [
Input.fromJson({'output_pointer':'0000000000000000000000000000000000000000000000000000000000000000:1'}),
];
List<ValueTransferOutput> outputs = [
ValueTransferOutput.fromJson({'pkh': 'wit174la8pevl74hczcpfepgmt036zkmjen4hu8zzs', 'time_lock': 0, 'value': 1000000000,}),
];
Future<VTTransaction> basicTransaction({
required List<Input> inputs,
required List<ValueTransferOutput> outputs,
required WitPrivateKey privateKey
}) async {
VTTransactionBody body = VTTransactionBody(inputs: inputs, outputs: outputs);
VTTransaction transaction = VTTransaction(body: body, signatures: []);
return transaction;
}
copied to clipboard
Send a transaction.
import 'package:witnet/node.dart';
import 'package:witnet/schema.dart' show VTTransaction, VTTransactionBody;

String nodeIp = '127.0.0.1';
int nodePort = 21338;

main() async {
NodeClient nodeClient = NodeClient(address: nodeIp, port: nodePort);
SyncStatus syncStatus = await nodeClient.syncStatus();
if (syncStatus.nodeState == 'Synced') {
// an empty transaction
VTTransactionBody body = VTTransactionBody(inputs: [], outputs: []);
VTTransaction transaction = VTTransaction(body: body, signatures: []);
String transactionID = transaction.transactionID;
// change to true if you really want to send the transaction
var resp = await nodeClient.inventory({'transaction': transaction.jsonMap});
print(resp);
}
}

copied to clipboard
Features and bugs #

Please file feature requests and bugs at the issue tracker.
Created by the Witnet Community and released under the GNU General Public License v3.0
Acknowledgment #
We would like to express our sincere gratitude to @parody_bit for generously creating and sharing this library for the improvement of the Witnet ecosystem. Thank you for your hard work and dedication.